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The parasitic effect inside through-silicon via (TSV) packaging under radio frequency (RF) operation may cause abnormal signals in circuit performance. On the bases of a self-developed deembedding technique, we investigated the high-frequency characteristics of a typical TSV structure through direct measurements. To this end, a silicon substrate layout was first designed and constructed, followed by packaging mounting to build a suitable setting for RF measurements. Behaviors up to 3 GHz on different circuit segments in an actual TSV packaging were then measured directly by using an RF-inductance, capacitance, and resistance (LCR) meter, and R, L, and impedance (Z) data for test structures were then extracted and compared with those reported in the literature. To study the environmental effect on the RF properties of the TSV test samples, we monitored behaviors during a temperature-humidity reliability test.

The contact resistance of microbumps in a plastic ball grid array packaging with a through-silicon-via (TSV) structure was characterized. Accordingly, a self-designed TSV daisy-chain circuit was proposed to facilitate the formulation of the measurement paths, and the test samples were made by using a commercialized packaging process to simulate real product behaviors. Using the proposed single model and the complete model for the testing structure, about 25 $\text{m}\Omega $ was measured as the average contact resistance per microbump, and the contact resistance for each microbump was separately extracted between 4 and 60 $\text{m}\Omega $ In addition, decreasing contact resistance due to the annealing effect was observed from two different reliability tests.

Through silicon via (TSV) is the key technology used in 2.5-D and 3-D packaging. Evaluating the reliability of products using this new technology has been challenging because of complex environmental factors. The aim of this paper was to design and implement a systematic reliability experiment to test self-designed TSV samples under the combinations of several different environmental variables. The Weibull distribution model was used to extract parameters from the experimental data for the statistical evaluation of TSV reliability. After analyzing the Weibull parameters, the environmental stresses that accelerate TSV unreliability were identified and compared, and a simple empirical unreliability equation was proposed. In addition, we observed that using a power law was an effective mean on making TSV reliability curve fittings. Failure analyses by optical microscopy, scanning electron microscopy, and energy dispersive spectrometer were finally reported.

Through-silicon via (TSV) is one of the key technologies on three-dimensional integration packaging. In this article, an experimental methodology with circuit models was proposed for electrical characteristic tests on typical TSV structures. To this end, self-developed test patterns such as the via chains, the snake interconnections and the Kelvin structures with different dimensions were designed and manufactured. Suitable electrical measurement methodologies were next employed to characterise the element behaviours of the patterns. Based on the experimental data, electrical circuit models for the TSV structures were introduced and the parameters of the model were exacted. The validity and accuracy of the electrical model were finally verified and the TSV characteristic measurements can be performed through a simpler process.

Because of the coefficient of thermal expansion and the hygroscopic swelling mismatches on plastic packaging materials, stress and reliability issues on microelectronic packaging structures are extremely important for the packaging industry. Through the self-design test chips with the piezoresistive microstress sensors, this paper presents the experimental methodologies for stress and reliability monitoring on typical plastic ball-grid-array packaging. To this end, coefficients of the sensors are first calibrated, and stress monitoring is next performed with simultaneously thermal and hygroscopic loadings under steady-state and cyclic environments, respectively. The Weibull reliability model is next applied based on the experimental data and the parameters of the model are extracted. After real-time monitoring on stress variations during the reliability test, about 0.8 MPa of stress decrease is measured on each reliability cycle.

Three-dimensional (3D) structure with through silicon via (TSV) technology is emerging as a key issue in microelectronic packaging industry, and electrical reliability has become one of the main technical subjects for the TSV designs. However, criteria used for TSV reliability tests have not been consistent in the literature, so that the criterion itself becomes a technical argument. To this end, this paper first performed several different reliability tests on the testing packaging with TSV chains, then statistically analyzed the experimental data with different failure criteria on resistance increasing, and finally constructed the Weibull failure curves with parameter extractions. After comparing the results, it is suggested that using different criteria may lead to the same failure mode on Weibull analyses, and 65% of failed devices are recommended as a suitable termination for reliability tests.

Moisture is one of the major contributing factors in fracture and reliability issues for microelectronic packaging. To characterize the moisture-induced stress distribution inside the packaging structure, an in situ, quantitative, and nondestructive experimental methodology is needed. This paper proposes the use of piezoresistive sensors to measure moisture-induced stress in a plastic low profile, fine pitch, ball grid array (LFBGA) packaging. The measurements include hygroscopic swelling stress extractions and real-time stress monitoring of the popcorn phenomenon, and the results associated with gravimetric analyses are reported. Postreflow scanning acoustic microscope (SAM) inspection results and cross section observations are used as experimental verification. Comparing with thermal stresses previously measured on the same package, it is found that the hygroscopic mismatch stress is significant and important for package engineers. In addition, piezoresistive sensors were proven useful in this work for recording popcorn occurrence and monitoring the stress drops at the popcorn initiation.

This paper develops a multifunctional test chip for property extractions on packaging design. Components on this test chip include the diodes as the temperature sensors; the polysilicon units as the heaters; the piezoresistors as the stress sensors; and the pads as well as the related metal connector designs for the electrical parameter extractions. To save the sensor numbers and the connecting wires, sensors on the test chip surface were put according to structure symmetry. Since each packaging design has its individual size, components on the test chip surface were laid based on assembly of small unit cells, so that flexible test chip size can be obtained to fit the requirements from different packaging dimensions. The inductance and capacitance for the packaging leads were also extracted under microwave frequency operations, and a testing fixture was built to cooperate the Quad Flat Package (QFP) samples with the RF-RLC meter. The availability of the new measurement system designs was demonstrated from...

In this work, a simple assembled structure was designed and fabricated so that the calibration procedures on piezoresistive stress sensors for microelectronic packaging can be simpler, more accurate, and more efficient. After comparing with the previous work results, validity of the aforementioned new structure has been demonstrated through experimental data. Since many accessory experimental facilities employed in traditional calibrations become unnecessary, the new methodology takes great advantage on piezoresistive coefficient extractions, especially for calibration at temperature other than room temperature.

In our previous works, the piezoresistive sensors have been demonstrated to be accurate and efficient tools for stress measurements in microelectronic packaging. In this study, we first designed test chips with piezoresistive stress sensors, temperature sensors as well as heats, and the test wafers were next manufactured through commercialized IC processes. Piezoresistive sensors on silicon strips, which were cut directly from silicon wafers at a specific angle, were then calibrated, and highly consistent piezoresistive coefficients were extracted at various wafer sites so that both normal and shear stress on the test chips can be measured. Finally, we packaged the test chips into 100-pin PQFP structures with different batches and measured internal stresses on the test chips inside the packaging. After measuring packaging induced stresses as well as thermal stresses on several batches of PQFPs, it was found that the normal stress diversities were obvious from different batches of the packaging structure, and the shearing stresses were approximately zero in all of the PQFPs at different chip site.

Stress measurements in microelectronic packaging through piezoresistive sensors take the advantage of both in-situ and nondestructive. In this study, test chips with both p-type and n-type piezoresistive stress sensors, as well as a heat source, were first designed, then manufactured by a commercialized foundry so that the uniformity of the test chips was expected. Both temperature and stress calibrations were next performed through a special designed MQFP (Metal Quad Flat Package) and four-point bending (4PB) structure, respectively. Measurements of stresses which are produced due to both manufacturing process and thermal effects on the test chips were finally executed, and approximately linear relationships were observed between stress and temperature as well as stress and input power. It is concluded that n-type piezoresistive stress sensors are able to extract stress in microelectronic packaging with good accuracy.

Based on experimental data, a simple R–C (thermal resistance–heat capacitance) model with software precaution strategies are proposed in this paper to predict the steady-state temperature of the circuit in an electronic packaging in real time. Further developments on the new methodology lead to real time monitoring if input power and/or the environment are changing during operations. It is concluded that the new methodologies, which make the over-temperature prediction much more reliable, efficient, sensible, and faster, can be easily employed for over-temperature protection designs on electronic packaging. [S1043-7398(00)00301-7]

Due to the carrier mobility changes with the mechanical loading and its small size, the MOSFET (metal-oxide-semiconductor field-effective-transistor) has the potential to be a suitable chip stress monitoring tool for microelectronic packaging. In this work, a complete and accurate approach to calibrate the coefficients for both types of MOSFET stress sensors under thermal and mechanical loadings was investigated quantitatively. Through data from different measurement modes on different types of MOSFET, the optimal experimental methodology was next proposed for the sensor applications on packaging stress extraction. The thermomechanical coupling coefficients for the selected experimental mode were finally extracted so that packaging stress measurements with MOSFET under elevated temperature can be performed more accurately.

Piezoresistive sensors have been demonstrated to be an accurate and efficient tool for stress measurements on chip surfaces inside microelectronic packaging. In this work, test chips with piezoresistive stress sensors, diode temperature sensors as well as heaters were first designed, fabricated, and calibrated. We next packaged the test chips into low profile, fine pitch ball grid array (LFBGA) packaging with 196 balls and measured the stresses on chip surfaces inside the packaging. After measuring the packaging induced stress as well as the stress under stable environmental temperature rises, it was found that compressive stresses were obtained at room temperature, and the stresses were relaxed as temperature went up at a rate between 0.45 MPa/°C and 0.60 MPa/°C. For thermo-stress experiments, the temperatures on chip surfaces at different power levels were measured, and compressive chip stresses were first extracted. As the chip power increased, the compressive stresses became tensions. Since the LFBGA structure is thinner with higher packaging efficiency, different results from our earlier plastic quad flat package stress measurements were observed and discussed. In addition, the final comparisons between the experimental data and the finite element simulations show good consistency.