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The metal-ferroelectric-metal (MFM) capacitor in ferroelectric random access memory (FeRAM) security embedded RFID chip is used not only in the memory cell region but also used in the analog and digital circuit area for low cost capacitance device and high security algorithm. MFM based security FeRAM braces for a wide range of security threats such as reverse engineering, cloning, and tampering. High security performance solution of on-chip FeRAM based register key is implemented to prepare against security attacking. RF transferring sensitivity properties with MFM capacitor are almost same or better than that with poly-insulator-poly (PIP) capacitor and metal-insulator-metal (MIM), and MOS capacitor. The measured power consumption of FeRAM embedded RFID chip without crypto processor engine is about 10μ W with the write sensitivity of -18dBm.

The metal-ferroelectric-metal (MFM) capacitor in the ferroelectric random access memory (FeRAM) embedded RFID chip is used in both the memory cell region and the peripheral analog and digital circuit area for capacitance parameter control. The capacitance value of the MFM capacitor is about 30 times larger than that of conventional capacitors, such as the poly-insulator-poly (PIP) capacitor and the metal-insulator-metal (MIM) capacitor. An MFM capacitor directly stacked over the analog and memory circuit region can share the layout area with the circuit region; thus, the chip size can be reduced by about 60%. The energy transformation efficiency using the MFM scheme is higher than that of the PIP scheme in RFID chips. The radio frequency operational signal properties using circuits with MFM capacitors are almost the same as or better than with PIP, MIM, and MOS capacitors. For the default value specification requirement, the default set cell is designed with an additional dummy cell.

New ZrO2/Al2O3/ZrO2 (ZAZ) dielectric film was successfully developed for DRAM capacitor dielectrics of 60 nm and below technologies. ZAZ dielectric film grown by ALD has a mixture structure of crystalline phase ZrO2 and amorphous phase Al2O3 in order to optimize dielectric properties. ZAZ TIT capacitor showed small Tox.eq of 8.5 A and a low leakage current density of 0.35 fA/cell, which meet leakage current criteria of 0.5 fA/cell for mass production. ZAZ TIT capacitor showed a smaller cap leak fail bit than HAH capacitor and stable leakage current up to 550 °C anneal. TDDB (time dependent dielectric breakdown) behavior reliably satisfied the 10-year lifetime criteria within operation voltage range.

To elucidate the prevalence and clinical implications of antineutrophil cytoplasmic antibody (ANCA) in lupus nephritis (LN), we examined ANCA by indirect immunofluorescence and by ELISA against antilactoferrin (anti-LF) and antimyeloperoxidase (anti-MPO) antibody. To discriminate perinuclear ANCA (pANCA) with antinuclear antibody (ANA), all the ANCA-positive sera were tested again after incubating patients’ sera with single-stranded (SS) and double-stranded (ds) DNA. These results were compared with clinicopathologic manifestations and clinical courses of LN. ANCA was positive in 19 (37.3%) of 51 LN patients. Among these LN patients, 3 had cytoplasmic ANCA (cANCA) and 16 had pANCA. ANCA was not found in 8 SLE patients without nephritis and 30 normal controls. The presence of ANCA, particularly pANCA, was associated with the presence of nephritis (18/51 cases vs. 0/8 cases, p < 0.05), especially with diffuse proliferative lupus nephritis, WHO class IV (17/18 cases vs. 21/31 cases, p < 0.05) as well as the presence of anti-dsDNA antibody (17/19 cases vs. 18/30 cases, p < 0.05). Patients with ANCA frequently had deterioration of renal function (3/16 vs. 0/26 cases). Anti-LF antibody was positive in 13 patients. Among those, 12 patients had nephritis. Five patients with anti-LF antibody did not have ANCA, but 7 had pANCA, and 1 had cANCA. Patients with anti-LF antibody had lower initial creatinine levels than those without it [serum creatinine (mg/dl): 0.78 (0.6–1.0) vs. 1.43 (0.5–5.0), p < 0.05]. Anti-MPO antibody was positive in only 1 patient, suggesting that MPO is a rare antigen for ANCA in LN.

In this study, the four different types of ArF and KrF OBARC have been evaluated to know the implantation blocking and gap fill performance for 80nm node device application. The boron implantation conditions of 11B and 49BF2 are processed and the minimum energy for implantation blocking of these OBARC are obtained by SIMS analysis. The minimum energy of ArF and KrF OBARC are about 13.0KeV and 15.0KeV, respectively. The chemical density of each OBARC is also calculated from the minimum blocking energy. Their values of ArF and KrF OBARC are about 0.8g/cm 3 and 1.0g/cm 3 , respectively. The minimum energy trends among the tested materials show the almost similar results with those of chemical density as expected. Even though the OBARC are composed of the similar chemical structure, they induce the different chemical density because of their own molecular weight and other additional structure as like chromophore. Both of KrF and ArF OBARC show the good gap fill performance on 0.2um size of via substrate and real topology pattern without void. It seems that the gap fill property is not much affected by the chemical structure or molecular weight of OBARC. It is thought that OBARC is an effective material for gap fill application than other resists, especially for deep topology patterns. In general, the etch rate of OBARC is slightly faster than that of ArF resist or similar with that in this experimental condition. The OBARC having high chemical density shows the slower etch rate and that of OBARC is inversely proportional to the chemical density of it. Therefore, it is confirmed that the OBARC is able to apply for implantation blocking purpose without gap fill void in real device below 80nm, since they have the good characteristics for gap fill, reflectivity control from substrate and implantation blocking property at a certain coating thickness.

Planarization characteristics of ultra low diluted Ceria (CeO2) based slurry, especially a multi-layered Chemical Mechanical Polishing (CMP) process, have been studied. The multi-layer represents the polished film consists of more than two different materials, so that, more than two different materials are exposed to the polished surface. In this work, ultra low diluted ceria based slurry was introduced to minimize micro-dishing effect of the process such as a storage node contact and a bit line contact in 80nm feature sized DRAM device, which has multi-layer film surfaces. As a result, we can minimize micro dishing of silicon dioxide and polycrystalline silicon at memory cell area, and silicon dioxide dishing at peripheral area.

A frequent problem encountered by photoresists during the manufacturing of semiconductor device is that activating radiation is reflected back into the photoresist by the substrate. So, it is necessary that the light reflection is reduced from the substrate. One approach to reduce the light reflection is the use of bottom anti-reflective coating (BARC) applied to the substrate beneath the photoresist layer. The BARC technology has been utilized for a few years to minimize the reflectivity. As the chip size is reduced to sub 100nm, the photoresist thickness has to decrease with the aspect ratio being less than 3.0. Therefore, new Organic BARC is strongly required which has the minimum reflectivity with thinner BARC thickness and higher etch selectivity toward resists. Hynix Semiconductor Inc., Nissan Chemical Industries, Ltd., and Brewer Science, Inc. have developed the advanced Organic BARC for achieving the above purpose. As a result, the suitable high performance 248nm Organic BARCs, NCA series, were achieved. Using CF4 gas as etchant, the plasma etch rate of NCA series is about 1.4 times higher than that of conventional 248nm resists. NCA series can be minimizing the substrate reflectivity at below 45nm BARC thickness. NCA series show the excellent litho performance and coating property on real device.

This paper discusses about the effectiveness of advanced e-beam inspection. Using an e-beam inspection system, the eS20XP (SN 158) from KLA-Tencor Corporation, DRAM development and ramp-up was accelerated. This was accomplished by analyzing the yield relevant electrical defects for process optimization at the critical steps of the wafer fabrication process flow. Through case studies on Self-Aligned Contact (SAC) poly plug layers, it was demonstrated that electrical process monitoring identified key issued in early stages of device development. These case studies also assisted in defining the narrow process window for the advanced 110 nm design rule DRAM devices at Hynix Semiconductor Inc.

The new thin BARC has been developed for the application of small size patterning below 100nm by the optimized simulation and the evaluations on each substrate condition of silicon nitride and silicon oxide. The optical parameters of thin BARC of Exp225 are 1.81 and 0.58 for n and k values, respectively. They are obtained by the simulation for the lower reflectivity at the conditions of silicon nitride and silicon oxide. The optimized BARC thickness of Exp225 are 320a and 460a for silicon nitride and oxide substrate, respectively, at the condition of reflectivity. These thickness are much lower than those of commercial BARC of DUV44 for the same substrate conditions. The pattern profile and process margin are compared between the inorganic SiON and organic BARC. The dense L/S pattern profile of 100nm size on SiON shows the severe standing wave and undercutting. However, the pattern on Exp225 is much stable and gives wider depth of focus margin than that of SiON condition. The 85nm dense L/S pattern with feasible process margin is obtained by the application of Exp225 at the thickness of 320a. The baking temperature is also investigated for the application of mass production. The most optimized baking temperature ranges of Exp225 are between 205°C and 225°C. From the experimental results, it is confirmed that the application of thin BARC is much effective for the small size patterning of 80nm node device. And it is thought that 80nm node device by KrF lithography is possible under the conditions of thin BARC, high contrast resist and high NA exposure tool.

In the scribe lane, which is located at the frame neighboring two chips, most of the test patterns for monitoring electrical characteristics of memory device as well as various key patterns for photo process are formed. The pattern density of these regions is lower than that of the main chip area, and cause nitride erosion by dishing phenomena during HSS STI CMP process. Nitride erosion occurred in the scribe lane region, could the affect erosion properties of cell region in main chip area, results in within die remain nitride variation and marginal fail in device operation. In this work, in order to prevent these problems, pattern design in the scribe lane was modified so as not to occurs within die remain nitride variation. The effects of improvement in within die remain nitride variation were investigated by FIB-TEM analysis and its correlation with electrical properties were explained.

We have investigated the characteristics of cell leakage and data retention time when using flowable oxide chemical vapor deposition (CVD) as a shallow trench isolation (STI) process of 1-Gbit DRAM. The trench gap filling capability was increased dramatically by combining high-density plasma (HDP) CVD with flowable oxide CVD. The reduced local stress by flowable oxide in narrow trenches leaded to decrease in junction leakage and gate induced drain leakage (GIDL) current and increase in data retention time of DRAM compared to HDP STI. Therefore, it is concluded that the combination of flowable oxide and HDP oxide is the most promising technology for STI gap filling process of sub-100 nm DRAM technology.

The diffusion parameters of chemical amplification resists are evaluated and analyzed as the functions of illumination condition, resist type and resist thickness. The pattern linearity is also compared among the different types of resist and process conditions. From the experimental results, it is confirmed that the diffusion parameters of dense L/S type resist is sensitively influenced by illumination condition, but those of C/H type resist are less affected by exposure condition due to the limited resolution of resist. Generally, the diffusion parameters seems to be much affected by sigma condition rather than the numerical aperture condition and it does not much influenced by resist thickness within similar thickness range. The 120nm, 100nm and 90nm dense L/S patterns are obtained with high contrast KrF resist of R5767 having diffusion parameter below 0.3 at the conditions of 0.80NA (89/60 sigma) and 2500 Angstrom thickness. Under the validation of DAIM, the most important parameter is the diffusion length of acid. Since the image contrast is given by the cross product of aerial image contrast and the resist function, the lithography performance depends upon not only the aerial image but also the resist function. The resist function is related with pattern pitch and diffusion length. Therefore, the increased value of resist function is required by introducing of high contrast resist having smaller diffusion parameter to induce the smaller pattern formation as explained in this experiment results.