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Glubam (glued-laminated bamboo) is a newly developed structural material with properties comparable to other wood and wood-based materials. Fiber-reinforced polymer (FRP) bar is an attract...

Gate oxide breakdown has always been a critical reliability issue in Complementary Metal-Oxide-Silicon (CMOS) devices. Pinhole analysis is one of the commonly use failure analysis (FA) technique to analysis Gate oxide breakdown issue. However, in order to have a better understanding of the root cause and mechanism, a defect physically without any damaged or chemical attacked is required by the customer and process/module departments. In other words, it is crucial to have Transmission Electron Microscopy (TEM) analysis at the exact Gate oxide breakdown point. This is because TEM analysis provides details of physical evidence and insights to the root cause of the gate oxide failures. It is challenging to locate the site for TEM analysis in cases when poly gate layout is of a complex structure rather than a single line. In this paper, we developed and demonstrated the use of cross-sectional Scanning Electron Microscope (XSEM) passive voltage contrast (PVC) to isolate the defective leaky Polysilicon (PC) Gate and subsequently prepared TEM lamella in a perpendicular direction from the post-XSEM PVC sample. This technique provides an alternative approach to identify defective leaky polysilicon Gate for subsequent TEM analysis.

Nowadays, physical failure analysis (PFA) technique of delayering by finger polishing is still widely used in FA labs, a method that is direct, simple, and flexible. However, with continuous technology scaling of semiconductor devices, conventional top down polishing method becomes more and more challenging with the increased number of transistors and layer stacks, introducing higher risk of sample damage. Therefore, not only new methods of sample preparation but also solutions for fixing problems are highly desired to cope with the increasing complexity of the modern IC devices. In this paper, advanced sample preparation techniques for rescuing damaged samples with cracks, scratches, or unevenness in delayering are introduced, through three typical rescue cases. These techniques are useful and critical for delivering FA results with high quality and high success rate, especially for those “one of a kind” devices.

As semiconductor technology keeps developing, failure analysis and device characterizations become more and more challenging. Global fault isolation without detailed circuit information comprises the majority of foundry EFA cases. That's why static fault isolation is majority part of the foundry EFA methodology. Limited pins will be biased with the static condition to access and trigger the defect, finally visualize it. Since the limited access pin and info were provided the static fault isolation has its intrinsic limitation, especially for the functionally failed unit analysis. So the different indirect methodologies were applied in the static analysis. The conventional and straightforward practice is to adjust the different bias condition to access and trigger the detect, trial and error. The other method is trying to select suitable and representative units for analysis. As long as some signal was triggered the subsequent analysis can be proceed on. For the functional fail the situation will be even worse because the failure mode is difficult to verify by the DC bias condition. In this paper a functional fail prototype issue was analyzed. DC bias shows normal for the units which customer's feedback show leakage under the functional testinge After the studying of the customer provided layout and circuit of the suspected block, we repetitively switch on and off of the power we biased on some of the pin. We manage to trigger the leakage mentioned by customer. With this kind of leakage hot spot was successfully observed. Combined with different hot spot of different bias condition and layout/circuit study, the failure mechanism was come out. It is a design related problem which was also accepted by the designer.

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Non-volatile memory is the most important memory device in IC chips. As a memory, embedded non-volatile memory (NVM) is a fundamental structure in many kinds of semiconductor devices. It is commonly used in the modern electrical appliance as a code or data memory. For different applications, there are different memory designs or IP, like ROM, OTP, Flash, MRAM, PCRAM etc. The physical mechanism of these NVMs are different, some are electron based, some are resistance based and fuse or anti-fused based. The experiment described in this paper is performed on an electron charge storage based NVM. That means a medium is employed to store electron charge to differentiate two statuses “0” and “1”. Floating Poly gate is this medium used as electron charge storage in this NVM. Since the storage medium is in floating condition, it cannot be accessed externally. The methods of performing direct analysis are limited for this kind of device, especially in the case of subtle defects or soft fail. As semiconductor devices scale, the defects become smaller and more subtle. Nanoprobing is usually the only way to find the defect location electrically before any further physical analysis. In this experiment, the single bit NVM fail was analyzed. Different PFA methods used during the analysis, failed to find the defect. Nanoprobing was employed to precisely isolate the defect. Key word: nanoprobing, NVM, subtle defect, Poly-crystalline, floating gate

Reliability tests, such as Time-Dependent Dielectric Breakdown (TDDB), High-Temperature Operating Life (HTOL), Hot Carrier Injection (HCI), etc., is required for the lifetime prediction of an integrated circuit (IC) product. Those reliability tests are more stringent and complex especially for automotive Complementary Metal–Oxide–Semiconductor (CMOS) devices, this because it involves human lives and safety. In foundries failure analysis (FA), Transmission Electron Microscopy (TEM) analysis often required in order to provide insights into the defect mechanisms and the root cause of the reliability tests. In this paper, application of high resolution Nano-probing Electron Beam Absorbance Current (EBAC), Nano-probing active passive voltage contrast (APVC), and TEM with Energy Dispersive X-Ray Spectroscopy (EDX) to identify the failing root cause of Inter- Poly Oxide (IPO) TDDB failure on an automotive grade Non- Volatile Memory (NVM) device was investigated. We have successfully demonstrated that TEM analysis after Nanoprobing EBAC/APVC fault isolation is an effective technique to reveal the failure root cause of IPO breakdown after reliability stresses.

This paper described a low yield case which resulted in a donut shape failing pattern. It also described a scenario where static fault localization is ineffective and a systematic problem solving approach based on symptoms, induction, hypothesis and verification was engaged to resolve the issue with understanding on the root cause and the failure mechanism. The low yield is due to residual light in the dilute HF clean tool which results in photovoltaic electrochemical effect on the exposed metal, through via holes, connecting to large PN junction. This results in subsequent resistive via formation and analogue failure.

With continuous technology scaling of semiconductor devices, conventional physical failure analysis (PFA) techniques becomes more and more challenging with the increased number of transistors and layer stacks. This paper presents a new memory bit-counting method in PFA by employing laser deprocessing technique (LDT). This LDT assisted new method is more cost-effective and efficient in the PFA on memory bit-counting in terms of shortening the total FA cycle time and lowering the requirements for the experimental equipment, which leads to the increase of PFA throughput in memory devices especially for high technology nodes.

Sample preparation plays a critical role in the failure analysis process of modern IC chips. The common problem in sample preparation is over-polishing. To reduce this problem, an AI-assisted monitoring system can be deployed, which can evaluate the progress of sample polishing process and suggest the steps following up. However, to build such an AI system, a tremendous number of images with proper classification are needed. To prepare these images, a reliable endpoint detection method for image analysis is necessary. In this paper, two endpoint detection methods are studied, and grayscale line profile analysis is discussed in detail. The current results are very promising for further development.

In wafer fabrication, sample preparation is becoming increasingly challenging as IC devices evolve to smaller feature sizes and higher densities. [1] Thus, the task of performing successful failure analysis (FA) is more challenging and difficult. Sample preparation is a key activity in material and failure analysis. In semiconductor, there are many different devices, process and design according to the customer requirement. Different FA approach for different devices and failure mode plays a very important role to help identify the root cause of the failure. This paper discusses the techniques used to ensure samples are kept in the best possible condition for the failure analyst. Also, we will discussed in-depth device study and the beauty of good sample preparation methodology through mechanical/chemical parallel polishing or etching together with correct FA approach or methodology to ensure good success rate in identifying failure on MIM breakdown. Two case studies will be discussed here to demonstrate how to identify the physical defect on Cu and Al process on MIM issue.

Low propagation loss waveguides are always preferred when making Si-photonics waveguide devices. However, light scattering due to sidewall roughness of waveguide contributes to the majority of signal losses. To reduce the loss, a reliable approach to measure the sidewall roughness is critical to fine-tune the fabrication process. In this paper, we report a direct sidewall roughness measurement method by using Atomic Force Microscopy (AFM) incorporated with a special scanning mode (Peakforce Tapping mode) and a point-terminated probe. This method has been successfully applied to measure the sidewall roughness of Si-Photonics waveguides for production process monitoring. The present method can also be applied to characterize the sidewall roughness of other nanostructures with similar requirements or situations.

Ginseng (Panax ginseng C.A. Meyer) belongs to the Araliaceae family and is a high-value medicinal herb grown mainly in Jilin Province, China. China is the world's oldest and largest producer of ginseng. Annual yield and exports account for more than 78 and 60% for the world, respectively. In July 2009 and August 2010, dodder (Cuscuta sp.), a parasitic seed plant, was observed on 4- and 5-year-old plants that were being cultivated on raised beds under artificial shading in three separate locations approximately 200 kilometers apart in Jilin Province. The infested area was approximately one-third of the field (300 m2 of 10,000 m2), which was previously planted with pine trees and herbaceous plants. Initially, there were no obvious symptoms on ginseng plants, but later, symptoms consisted of poor growth, chlorosis, and wilting, eventually followed by death in large areas throughout the field. One typical representative of 10 samples collected was identified as Cuscuta japonica based on several morphological characteristics, including yellow stems with purplish spots with branches 1.2 to 2.5 mm in diameter. Inflorescences were spicate and measured 3 cm with broadly ovate, scale-like bracts. Flowers were sessile with deeply divided calyxes. The parasite had purplish, ovate sepals with pink or greenish white corollas. The plant had five stamens with yellow, ovate-circular anther. Ovaries were globose and smooth. Capsules contained three to four pale yellow or brown ovate seeds measuring 1.9 to 2.7 mm (3,4). The internal transcribed spacer (ITS) region of rDNA of the representative samples was amplified using primers ITS4/ITS5 (2) and sequenced. BLASTn analysis of the 650-bp amplicon (GenBank Accession No. JF431541) showed 99% sequence identity with C. japonica (Accession Nos. DQ924571 and EU330320). Phylogenetic trees constructed by utilizing the neighbor-joining method with software MEGA 4.0 (1) placed the dodder specimens and C. japonica (DQ924571 and EU330320) into one group. The reported hosts of C. japonica include plants belonging to the Leguminosae, Salicaceae, Polygonaceae, and Compositae. Therefore, to our knowledge, this is the first report of C. japonica naturally infecting P. ginseng in the world. Reference: (1) K. Tamura et al. Mol. Biol. Evol. 24:1596, 2007. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990. (3) Z. Y. Wu. Flora Reipublicae Popularis Sinicae 64:147, 1979. (4) L. P. Yin. Plant Quarantine (in Chinese) 9:292, 1995.

Schisandra (Schisandra chinensis (Turcz.) Baill) is an important medicinal herb in China, which is mainly used for treatment of insomnia and memory decay. In September 2010, rot was observed on approximately 5% of the fruits during ripening of schisandra in several orchards at Linjiang City and Ji'an City, Jilin Province. Watery spots on infected fruits of schisandra appeared at the end of ripening, and then the fruits darkened in color, shrunk, and turned soft. The surface of the lesions became covered with masses of blue-green mycelium, conidiophores, and conidia under high humidity. To isolate the causal agent, conidia and conidiophores were suspended in sterile water and streaked onto the surface of potato dextrose agar (PDA). Single hyphal tips were then transferred to new PDA plates to be purified. The isolates were then cultured on CYA (Czapek yeast extract agar) and two kinds of strains (wwzqm1 and wwzqm2) were established based on differential growth rate, microscopic features, and colony color. Pathogenicity of each strain was tested on 25 healthy mature fruits of schisandra cv. Red Pearl by inoculating the fruit surface with a 15 μl conidial suspension (106 conidia/ml). Control fruits were treated with sterile water. Fruits were kept at 25°C and 90% relative humidity. After a 5-day incubation, symptoms described above were observed on all inoculated fruits, whereas all control fruits were symptomless. The causal agent was reisolated, confirming Koch's postulates. Strain wwzqm1 was identified as Penicillium glabrum (Wehmer) Westling on the basis of its morphology. Conidiophores arose from basal hyphae, with stipes smooth or finely roughened, 50.5 to 300.0 × 2.5 to 3.5 μm, penicillus monoverticillate, and bearing verticils of 8 to 12 phialides. Conidia were globose to subglobose, approximately 2.9 to 3.5 μm in diameter, with smooth or nearly smooth walls, and conidial chains in compact columns. Colonies grown for 7 days on CYA at 25°C attained a diameter of 32.4 to 39.1 mm, with the center of a deep bluish green, plane, velutinous, and heavily sporulated. Margin mycelium of the colony was white, with a yellowish brown under surface. Strain wwzqm2 was identified as P. adametzii K. M. Zalessky according to its morphological features with conidiophores born from funicolose hyphae, stipes smooth, 10.2 to 20.1 × 1.5 to 2.5 μm, penicillus monoverticillate, and bearing verticils of 4 to 6 phialides. Conidia were nearly globose to glubose, 2.0 to 2.7 μm in diameter, with smooth or finely roughened walls, and conidial chains loose and irregular. Colonies on CYA at 25°C for 7 days grew rather fast and reached a diameter of 50.3 to 60.2 mm, and were deep grayish green, near plane, floccose or funicolose, and heavily sporulated. Margin mycelium of the colony was white with a yellowish brown under surface (1). The internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) was amplified for wwzqm1 and wwzqm2 using primers ITS4/ITS5 and sequenced. BLASTn analysis of the 595 bp wwzqm1 (GenBank Accession No. JN887323) amplicon had 99% sequence identity with P. glabrum (DQ681321) and the 568 bp wwzqm2 amplicon (JN887322) had 99% sequence identity with P. adametzii (AF033401). To our knowledge, this is the first report of fruit rot on S. chinensis caused by P. glabrum and P. adametzii in China. Reference: (1). H. Z. Kong. Penicillium et Teleomorphi Cognati. Flora Fungorum Sinicorum. Science Press, Beijing, 35:43, 2007.

Nondestructive ultrasonic testing is known as a very efficient inspection method for detecting defects in concrete and steel structures. In order to apply this method for inspecting the quality of the cold-pressing glue-lines in glued laminated bamboo (glubam) components, a series of rheological performance tests and the ultrasonic transmission tests were conducted on modified adhesives and on glubam specimens with cold-pressing glue-lines, respectively. Focuses are on the gap filling ability of the adhesive and the defect threshold of the glue-line by using nondestructive ultrasonic testing. An optimal modified adhesive and the corresponding control spray amount were provided for manufacturing glubam components based on the rotational viscosity test and proposed sagging test. The initial amplitude of received signal is selected as the acoustic parameter to identify the glue-line defects in glubam specimens, and a defect criterion is proposed by using the ultrasonic transmission method. Verification test results indicate that the proposed defect judgment method has good feasibility and accuracy.

With continuous scaling on CMOS device dimensions, it is becoming increasingly challenging for conventional failure analysis (FA) methods to identify the failure mechanism at the circuit level in an integrated chip. Scanning Electron Microscopy (SEM) based nanoprobing is becoming an increasingly critical tool for identifying non-visual failures via electrical characterization in current electrical FA metrology for fault isolation since 2006 Toh et al. (2007), Shen et al. (2007), Ng et al. (2012) . Currently, most of the nanoprobing fault isolation is nanoprobe in top-down planar direction, such as nanoprobe on via, contact and metal line. This paper focused on fault isolation of sub-micron devices by nanoprobing on a cross-sectional plane. This is a new application area; it is very useful for sample that cannot perform fault isolation with conventional top-down planar nanoprobing, especially on non-volatile memory that with single transistor memory array that arrange in a vertical direction, such as Magnetic Random Access Memory (MRAM), Phase-Change Random Access Memory (PC-RAM), flash memory and etc.

Cross-sectional analysis is one of the important areas for physical failure analysis. Focus Ion Beam (FIB) and mechanical polish sample preparation are commonly used and necessary techniques in the semiconductor industry and Failure Analysis (FA) Company (Wills and Perungulam, 2007). However, each technique has its own limitation. Mechanical polishing technique easily induces artifact by mechanical force, especially on advance technology node. FIB can eliminate mechanically damaged artifact, but have the limitation on cross-sectional view area. Another potential technique will be plasma FIB, it used very high milling current and fast milling speed (Hrnciř et al., 2013). However, it comes with a very high cost and having the contamination issue. The contamination issue greatly affects the low kV Scanning Electron Microscopy (SEM) imaging quality. In recent semiconductor industry FA, low kV SEM imaging is preferable, because high kV imaging will introduce delamination artifacts especially on organic material from packaged sample. In this paper, Fast Laser Deprocessing Techniques (FLDT) application is further enhanced on large area cross-sectional FA with fast cycle time and low-cost equipment. This is to prevent from mechanical damage. In short, the proposed FLDT is a cost-effective and quick way to deprocess a sample for defect identification in cross-sectional FA.

Fiber can improve the bending strength of cement mortar or concrete due to its high toughness. The straw fiber, SF and PF with different properties were mixed into the mortar in the same proportion and different mixing processes to prepare mortar specimens, and the different types of fibers were mixed for the standard curing 7d and 28d. The mechanical properties of the test piece affected the change in this study. The results were showed as follows: the strength of the mortar with straw fiber was higher than that of the post-mixing method, and the flexural strength (referred to as FS) was increased by about 16.0%; the FS of the mortar after the SF was added by 9.7% higher than that of the first blending method, but the compressive strength(referred to as CS) of the first mixed mortar was higher than that of the post-mixing method 16.9%, indicating that the SF had a high modulus of elasticity, which could improve the CS; the growth trend between the FS and CS of the mortar were close with PF. Under the SF first mixing process, the CS was maximized, followed by the PF at the post-mixing method, and the worst was the post-mixing method of the straw fiber.

Antibody-mediated rejection (AMR) is an important factor affecting survival after renal transplantation. A highly selective proteasome inhibitor, bortezomib, clears activated plasma cells from the body and has important therapeutic effect on AMR. We investigated the effects of bortezomib on AMR in a patient after a second renal transplant. Biopsy confirmed the diagnosis of mixed cellular rejection and AMR. Bortezomib was administered on day 1 (1.3 mg/m(2)), day 4 (1.0 mg/m(2)), and day 8 (1.0 mg/m(2)). On the same days, 250 mg methylprednisolone was administered once, and cyclosporine dose (5 mg·kg(-1)·day(-1)) was reduced by 50%. Oral mycophenolate mofetil and steroid were withdrawn on day 1 of bortezomib treatment. Intermittent double-filtration plasmapheresis was also performed. We monitored parameters, including T lymphocyte subsets, CD139 and CD19 expression, panel reactive antibody (PRA), and serum creatinine concentration. At follow-up 6 months after bortezomib treatment, we observed: 1) serum creatinine stabilized at 130 μM from a peak level of 337 μM; 2) PRA decreased from a maximum of 66.7 to 0%; 3) blood plasma cell percentage rebounded after significantly decreasing following the first dose of bortezomib; 4) in renal allograft biopsy, immunohistochemical staining for C4d shifted from strongly positive to negative, and cellular rejection shifted from type IIA to borderline; and 5) adverse effects such as platelet suppression, hypotension, and grade 3 peripheral neuropathy emerged. Bortezomib effectively treated antibody-mediated renal transplantation rejection in this case study, but clinical trials with large sample sizes are still needed to explore clinical safety and tolerability.

This paper places a strong emphasis on the importance of applying the correct FA approach in physical sample preparation to identify hidden defects that can be easily removed during analysis. A combination of mechanical parallel polishing and chemical etching was used during the sample preparation after electrical fault isolation. Such a combination is both effective and efficient in identifying the single Via punch-through from a sea of Via in MIM structure as well as finding the thin layer of barrier bridging under the Al metal. It serves as a quick way to verify any suspect without time consuming FIB progressive cuts at the hotspot location which sometimes turns out to be an induced spot with a defect located at other site due to the circuitry connection. It would serve as a good reference to wafer fab that encountered such issues.

This paper illustrated the beauty of AFP nanoprobing as the critical failure analysis tool in resolving the one-time programmable (OTP) non-volatile memory data retention failures through electrical simulation in wafer fabrication. Layout analysis, electrical simulation using Meilke’s method, UV erase methodology (to differentiate between mobile ion Meilke’s method contamination and charge trap centers) and a few other FA approaches were employed to determine the different root causes in the three OTP failure case detailed in this paper.. These include SiN trap center issue, poly stringers and abnormal layer at the initial CESL (Contact etch stop layer) nitride. This paper placed a strong emphasis on systematic problem solving approach, deep dive and use of right FA approach/tool that are essentially critical to FA analysts in wafer foundry since there is always minimal available data provided. It would serve as a good reference to wafer Fab that encountered such issue.

SRAM is a major component in semiconductor industry which often requires extensive and exhaustive method of fault isolation, especially for a non-visual defect in a soft failure mode. For these cases, nanoprobing on CA layer is often performed but there are times when it fails to isolate any defect. One reason may be because the failure only occurs at high temperature test environment. This paper will discuss the effectiveness of high temperature nanoprobing for SRAM soft failure fault isolation. 3 different case studies result from 3 similar SRAM devices which failed at high temperature test environment will be analyzed in this paper.

As the applications of micro electronic mechanical system (MEMS) are booming, more and more research and development activities are involved in the MEMS industry. For every new MEMS product with new functions, the manufacturing process will be tailored to cope with the changes. This requires reliability work to ensure the robustness of the new process. Thus, failure analysis plays an important role in the process development and the success rate for MEMS FA will be critical. In this paper, we will discuss a new decapsulation approach using a wedge diamond indenter based tool. It is a pure mechanical method and most of all, the whole process can be visually guided and monitored with the onboard optical vision system. The precision knob based operation is controllable, which makes the success rate very high by every user. We have successfully applied this method to our MEMS FA cases and this paper will detail our experiences.

Although nano-particles have attracted extensive studies in material science and technology for decades, how to measure the particle size efficiently and conveniently still remains to be a problem unsolved. In this paper, Si nano-particles prepared by annealing a very thin amorphous Si layer were inspected by atomic force microscopy (AFM) as well as SEM and TEM e-beam techniques. Results extracted from AFM images are larger than those from e-beam imaging techniques mainly due to AFM probe tip convolution effect. In order to correct the AFM tip/probe induced topography convolutions, strategy and approaches were explored by constructing a suitable tip geometry model and then applied to the different scenarios when particle size is larger or close to the tip radius. The conclusions are consequently applied to the current study and the corrected AFM results are satisfying.

Anesthetic management of patients with dilated cardiomyopathy (DCM) is a challenge to the anesthesiologist, due to poor left systolic function, ventricular enlargement, risk of malignant arrhythmias and sudden cardiac death. Therefore, preoperative assessment and appropriate anesthetic management are important in patients with DCM. This review describes the preoperative evaluation and anesthesia considerations of patients with DCM undergoing non-cardiac surgery. Patient pathophysiology and clinical status, such as ventricular function, degree of myocardial fibrosis, resting heart rate and high-sensitivity C-reactive protein can affect survival rates. Advanced monitoring devices, such as transesophageal echocardiography and cardiac resynchronization therapy can be used to assess ventricular function and myocardial fibrosis. Thoracic epidural blockade can improve ventricular function. In summary, the optimal anesthetic management of patients with dilated cardiomyopathy requires good preoperative assessment, close perioperative monitoring, suitable anesthetic, optimization fluid management, and stable hemodynamic status.

A good combination of high tensile strength as well as large elongation and low coercivity is achieved by optimal precipitation for FeCo-2V-Cr alloy. The precipitate is characterized by bcc structure with plate-like contrast and is disordered phase due to its enrichment of V and Cr in contrast to the partial ordering observed in matrix phase. The Cr addition is significant in such precipitation that leads to the improvement of both tensile strength and ductility without deteriorating soft magnetic property.

This paper discussed on how the importance of failure analysis to identify the root cause and mechanism that resulted in the MEMS failure. The defect seen was either directly on the MEMS caps or the CMOS integrated chip in wafer fabrication. Two case studies were highlighted in the discussion to demonstrate how the FA procedures that the analysts had adopted in order to narrow down to the defect site successfully on MEMS cap as well as on CMOS chip on MEMS package units. Besides the use of electrical fault isolation tool/technique such as TIVA for defect localization, a new physical deprocessing approach based on the cutting method was performed on the MEMS package unit in order to separate the MEMS from the Si Cap. This approach would definitely help to prevent the introduction of particles and artifacts during the PFA that could mislead the FA analyst into wrong data interpretation. Other FA tool such as SEM inspection to observe the physical defect and Auger analysis to identify the elements in the defect during the course of analysis were also documented in this paper.

As semiconductor technology keeps scaling down, failure analysis and device characterizations become more and more challenging. Global fault isolation without detailed circuit information comprises the majority of foundry EFA cases. Certain suspected areas can be isolated, but further narrow-down of transistor and device performance is very important with regards to process monitoring and failure analysis. A nanoprobing methodology is widely applied in advanced failure analysis, especially during device level electrical characterization. It is useful to verify device performance and to prove the problematic structure electrically, especially for implantation related problems [1] [2]. Implantation related defects, or invisible defects, are the most challenging defect types for the application of fault isolation in all of the failure analysis jobs. The key challenge for these kinds of analyses is to make the defect visible. Sometimes, it is difficult or even impossible to visualize the defective point. Then, sufficient electrical evidence and theory analysis are important to bring the issue to resolution. For these kinds of analyses, a nanoprobing system is a necessary tool to conduct the detailed analysis. Combined with the device physics and electrical theory analysis, nanoprobing can bring out the perfect failure mechanism and problematic process step. There are two popular nanoprobing systems in our lab, one is SEM based and the other is AFM based. Both systems have their advantages and disadvantages in the electrical characterization and fault isolation field. In this paper, an implantation related issue was analyzed. Gross leakage was observed on the failed units as compared with good units. Global fault isolation, TIVA and EMMI failed to find the exclusive hotspot. With the GDS and process analysis, the nanoprobing was employed to the performance check on some of the suspected structures. Finally, the defective location was successfully isolated by nanoprobing. Combined with device physics and electrical analysis, the problematic process was successfully isolated.

As the semiconductor technology continues to scale, the stability and performance of embedded SRAM are growing concerns during the design and analysis stages. Maintaining an acceptable Static Noise Margin (SNM) in the embedded SRAM while scaling the minimum feature size and supply voltage of the integrated circuit (IC) becomes increasingly challenging. As a result, the manufacturing process window continues to shrink. This increases the difficulty for the failure analysis as many soft failures are induced by the reducing process margin. In this paper, a case study on an advanced technology node embedded SRAM soft fail was analyzed. Nanoprobing was employed at the room temperature to do SNM analysis at Metal 1 on the suspected location. Abnormal SNM window was observed at the room temperature analysis. Further analysis at high temperature on the same bit confirmed the soft failure bit. This correlates to the testing failure mode result. This case study is a good example for others who encounter same kind of the embedded SRAM soft failure.

In the summer of 2015, dark brown lesions were observed on green husk pumpkin cultivar Xiangli No. 23, in Changchun (125.39°E, 43.45°N), Jilin Province, China. Nearly half of the plants in a 0.01-ha field of pumpkin were symptomatic. Symptoms on fruit were initially irregular dark green spots of 2 mm in diameter. As the disease progressed, spots expanded and gradually became round or oval, and the outside and inside of the necrotic areas became black. With higher humidity, abundant white aerial mycelia were produced on the black disease spots and orange conidial cirrhi visible in concentric rings on the margins of the lesions, and fewer acervuli were seen. Finally, the fruit were rotten. To isolate the pathogen, small pieces of symptomatic fruit were surface sterilized in 1.5% NaOCl for 1 min, washed twice with sterile distilled water, and then placed onto potato dextrose agar (PDA). Monoconidial isolate CCCM12 was grown on PDA under a 12-h photoperiod at 25°C. The color of the upper surface of the colony varied from white to off-white with cottony aerial mycelium, and was pale to orange with heavy sporulation on the underside. Conidia (n = 150) were one-celled, straight, hyaline, cylindrical with round ends (98%) or one end with acute apices (2%), smooth-walled, guttulate, and measured 10.8 to 21.4 (16.3 ± 2.1) μm in length and 3.6 to 10.4 (5.7 ± 1.0) μm in width. Appressoria (n = 50) were brown to dark brown, variable in shape including ovoid, clavate, or slightly irregular, and measured 4.9 to 14.5 × 4.7 to 10.8 μm. Based on morphological characteristics, the fungus was preliminarily identified as Colletotrichum brevisporum following descriptions of Noireung et al. (2012). The internal transcribed spacer (ITS), β-tubulin (TUB2), actin (ACT), and chitin synthase (CHS-1) gene regions of isolate CCCM12 were amplified by using ITS4/ITS5, Bt2A/Bt2B, ACTF/ACTR, and CHSF/CHSR primers, respectively (Weir et al. 2012). Their GenBank accession numbers were obtained and were submitted to GenBank. A BLAST search revealed that all sequences (GenBank accession nos. KY797632 for ITS, KY797630 for TUB2, KY797629 for ACT, and KY797631 for CHS-1) matched with 99 to 100% identity to C. brevisporum (KC790943 for ITS, JN050244 for TUB2, JN050217 for ACT, and KF687760 for CHS-1). Molecular phylogenetic trees constructed using MEGA7 confirmed this. To confirm pathogenicity, following Bezerra et al. (2016), 5-mm-diameter hyphal plugs were taken from a 7-day-old culture of CCCM12 and singly placed on each of 15 mature and healthy Xiangli No. 23 pumpkins superficially wounded with a sterilized needle. In control fruits, only PDA discs without fungal growth were used. Fruits were covered with plastic bags and incubated in a growth chamber at 25°C at 95% relative humidity. Symptoms (pale to black sunken lesions) developed on inoculated fruit 6 days after inoculation. No lesions were observed on control fruit. When fungi were reisolated from lesions of inoculated fruit onto PDA, colony and conidial morphology were identical to the original isolate. The experiment was performed three times. The fungus was placed in the Herbarium of Mycology of Jilin Agricultural University. This pathogen has been previously reported on Pandanus pygmaeus and Lycium chinense in Thailand and Korea (Noireung et al. 2012; Paul et al. 2014), on fruits of Carica papaya and Sechium edule in Brazil (Bezerra et al. 2016; Vieira et al. 2013), and on pepper fruits in China (Liu et al. 2016). This is the first report of C. brevisporum causing anthracnose on green husk pumpkins.

China is the top kiwifruit producing country worldwide, approximately 10,000 ha of commercial production (Li et al. 2016; Wang et al. 2017). About 10% of the kiwifruits harvested from several Chinese cultivars including Jinyan, Hongyang, and Qinmei in several fruit markets from Shaanxi (Xi’an city) and Sichuan (Dujiangyan city) provinces of China had postharvest rot in 2015 and 2016. All fruits were collected from the fruit markets and the symptoms were observed. Symptoms appeared as soft, light to dark brown, sunken lesions which gradually became round or oval. The lesions often started from the pericarp and then extended to the whole fruit. To isolate the pathogen, small pieces (5 mm length) of the lesion margin collected from ten diseased fruits were surface-sterilized in 0.1% HgCl2 for 1 min, 75% ethanol for 30 s, rinsed twice with sterile distilled water, placed on potato dextrose agar (PDA), and incubated for 4 days at 25°C. Then, eight pure cultures were obtained by single-spore culturing (Fs-c-1 t...

Monitoring the pathogenic fungus of wheat stripe rust, Puccinia striiformis f. sp. tritici, plays a key role in effective control of the disease. In the present study, we developed a specific and sensitive polymerase chain reaction (PCR) assay for detecting the pathogen in wheat (Triticum aestivum) leaves. A pair of primers (PSF and PSR) was designed based on the internal transcribed spacer (ITS) region sequence of P. striiformis f. sp. tritici. PCR products that were amplified with universal primers ITS1 and ITS4 were cloned into pGEM-T Easy vectors and sequenced. The ITS sequence was compared with those of P. striiformis f. sp. tritici, P. triticina, P. graminis f. sp. tritici, Blumeria graminis f. sp. tritici, Fusarium graminearum, Rhizoctonia cerealis, and Bipolaris sorokiniana, which are associated with early symptoms of foliar diseases on wheat. Specificity of the primers was tested in the PCR assays using DNA extracted from all tested P. striiformis f. sp. tritici isolates, other fungal species, and healthy and infected wheat leaves sampled around stripe rust foci in wheat fields, different days after inoculation with P. striiformis f. sp. tritici, as well as asymptomatic wheat leaves sampled around stripe rust foci in the fields. A PCR product of 169 bp was amplified from DNA of all P. striiformis f. sp. tritici isolates. The primers did not amplify DNA from the other tested fungal species. The pathogen was detected from asymptomatic wheat leaves inoculated with P. striiformis f. sp. tritici under greenhouse conditions, as well as leaves sampled around stripe rust foci in wheat fields. Under optimum conditions, the PCR assay was highly sensitive and required only 0.1 pg of the target DNA for a detectable and reliable amplification with the PSF and PSR primers.

The optical and structural properties of quaternary AlInGaN layers grown by a pulsed metalorganic chemical vapor deposition (PMOCVD) have been investigated by means of photoluminescence (PL) and time-resolved PL (TRPL) measurements and X-ray diffraction. The AlInGaN layers show strong blueshift and linewidth broadening of the PL emission band with increasing excitation power. With increasing indium mole fraction, the AlInGaN layer exhibited a stronger PL intensity, a faster PL decay, and a smaller lattice mismatch between the AlInGaN layer and the GaN buffer layer. Based on both the PL and TRPL data, we suggest that the incorporation of indium creates more band-tail states and enhances the luminescence efficiency, indicating that the PMOCVD-grown AlInGaN is better suited as the active region material for ultraviolet light-emitting diodes than conventional MOCVD-grown AlInGaN.

This paper describes the debug and analysis process of a challenging case study from wafer foundry which involved a circular patch functional leakage failure that was induced from device parametric drift due to thicker gate oxide with no detection signal from inline monitoring vehicles. It highlights the need for failure analyst to always be inquisitive and to deep dive into the failure symptoms to value-add the fab in discovering the root cause of the failure in challenging situation where information is limited.

As the semiconductor technology keeps scaling down, Poly silicon gate pattern becomes more and more critical. If the Poly silicon variation is too big or some mismatch, it will induce severe logic parametric fail or even functional fail, whi ch is difficult for the failure analysis. For the analog device, it ca n induce functional fail. In this case, a function related failure was analyzed an d the level shift circuit was identified. No visible defect was found until contact level by physical FA (PFA) on the structure. Atomic force probing was applied on the device level analysis. After the preliminary probing, an in-depth nanoprobing experiment was designed in order to narrow down the root cause of defect. Based on the electrical analysis, PFA was performed and systematic Poly shrink was found in the specific location which correlates with the process issue.

Embedded non-volatile memory (NVM) introduces additional thermal processes to a logic process flow and the impact from this extra thermal budget becomes more considerable with continued device scaling. This paper investigates the mechanism of SRAM V MIN degradation in a 40nm embedded NVM process and provides a solution to address the degradation caused. Failure analysis shows enlarged poly grain size for SRAM PMOS due to the NVM thermal processes, resulting in a large shift in threshold voltage. The results show that introduction of a p-poly boron pre-dope greatly helps to recover the SRAM V MIN . The mechanism for the V MIN recovery is also explained, with further high-temperature SRAM V MIN studies showing the effectiveness of p-poly pre-dope even at elevated temperatures.

Data regarding the cerebral atherosclerotic stenosis (CAS) and incidence of stroke are conflicting. The number of stroke patients is more than three times that from coronary heart disease in China. The main aim of this report is to review the current status of intracranial and extracranial atherosclerotic stenosis including epidemiology, diagnosis, treatment and risk factors in China.Data was identified by searches of MEDLINE (January 1966 to December 2008), China Biological Medicine Database (CBM-disc 1979 to 2008), China National Knowledge Infrastructure (CNKI 1994 to December 2008).The occurrence of intracranial artery stenosis was more frequent than that of extracranial artery in the Chinese population. TCD, Doppler ultrasound, CTA, MRA and DSA techniques are established to examine intracranial and extracranial atherosclerotic stenosis in China. Evidence-based treatments and CAS are more commonly applied in patients with cerebrovascular stenosis in China. However, the development of carotid endoarterectomy (CEA) is limited in Chinese communities. The risks of cerebral atherosclerotic stenosis include age, hypertension, diabetes mellitus, dyslipidemia, smoking and metabolic syndrome.Further studies are needed to focus on the intracranial atherosclerotic stenosis.