Thermo-mechanical modeling of stacked die flash memory package EMI shielding layer crack under thermal cycling test

Traditional thick film technology is widely used in various electronics products. There are two type of paste based on thick film technology. Typically, over 400°C is required for high temperature sintering type which contains glass for adhesion function. It shows high electrical and thermal performance. On the other hand, 150–300°C range process is used for low temperature process type as silver epoxy. In last decade, nano silver technology shows amazing progress to address low temperature operation by low temperature sintering. This paper will discuss the results on fundamental study of newly developed nano silver pastes with unique approach which uses MO (Metallo-organic) technology and resin reinforcing technology. Nano silver pastes contain several types of dispersant as surface coating to prevent agglomeration of the particles. Various coating technique has been reported to optimize sintering performance and stability. MO technology provides low temperature sintering capability by minimizing the coating material. The nano silver pastes show high electrical and thermal performance. However, degradation of die shear strength has been found by thermal cycling test due to the fragility of porous sintered structure. To improve the mechanical property, resin reinforcing technology has been developed. By adding special resin to the pastes, the porous area is filled with the resin and the sintered structure is reinforced. Degradation of die shear strength was not found by thermal cycling test to 1000 cycles. Nano silver pastes using MO technology and resin reinforcing technology will meet lots of requirement on various thick film applications.

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Reliability of Fan-Out Wafer-Level Heterogeneous Integration

Journal of Microelectronics and Electronic Packaging ◽

10.4071/imaps.728940 ◽

2018 ◽

Vol 15 (4) ◽

pp. 148-162 ◽

Cited By ~ 9

Author(s):

John Lau ◽

Ming Li ◽

Yang Lei ◽

Margie Li ◽

Iris Xu ◽

...

Keyword(s):

Thermal Cycling ◽

Printed Circuit Board ◽

Solder Joints ◽

Circuit Board ◽

Heterogeneous Integration ◽

Thermal Cycling Test ◽

Wafer Level ◽

Molding Compound ◽

Shock Test ◽

Cycling Test

Abstract In this study, the reliability (thermal cycling and shock) performances of a fan-out wafer-level system-in-package (SiP) or heterogeneous integration with one large chip (5 × 5 mm), three small chips (3 ×3 mm), and four capacitors (0402) embedded in an epoxy molding compound package (10 × 10 mm) with two redistribution layers (RDLs) are experimentally determined. Emphasis is placed on the estimation of the Weibull life distribution, characteristic life, and failure rate of the solder joint and RDL of this package. The fan-out wafer-level packaging is assembled on a printed circuit board (PCB) with more than 400 (Sn3wt%Ag0.5wt%Cu) solder joints. It is a six-layer PCB. The sample sizes for the thermal cycling test and shock test are, respectively, equal to 60 and 24. The failure location and modes of the thermal cycling test and shock test of the fan-out wafer-level SiP solder joints and RDLs are provided and discussed. 3-D nonlinear finite element models are also constructed and analyzed for the fan-out heterogeneous integration package during thermal cycling and shock conditions. The simulation results are correlated to the experimental results. Finally, recommendations on improving the fan-out wafer-level SiP solder joints and RDLs under thermal and shock conditions are provided.

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Thermal cycling test of few selected inorganic and organic phase change materials

Renewable Energy ◽

10.1016/j.renene.2008.02.026 ◽

2008 ◽

Vol 33 (12) ◽

pp. 2606-2614 ◽

Cited By ~ 171

Author(s):

Anant Shukla ◽

D. Buddhi ◽

R.L. Sawhney

Keyword(s):

Thermal Cycling ◽

Phase Change ◽

Organic Phase ◽

Phase Change Materials ◽

Thermal Cycling Test ◽

Cycling Test ◽

Inorganic And Organic

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Effect of Thermal Cycling on Operational Characteristics and Lifetime Prediction of Space Pulse Tube Refrigerator

Mathematical Problems in Engineering ◽

10.1155/2019/6410704 ◽

2019 ◽

Vol 2019 ◽

pp. 1-15

Author(s):

Fubin Wan ◽

Xun Chen ◽

Zhenhua Jiang ◽

Yinong Wu

Keyword(s):

Thermal Stability ◽

Thermal Cycling ◽

Estimation Method ◽

Cooling Capacity ◽

Lifetime Prediction ◽

Test Scheme ◽

Pulse Tube ◽

Thermal Cycling Test ◽

Degradation Model ◽

Cycling Test

This paper presents the operation status and results of ground thermal cycling test of pulse tube refrigerators (PTRs) for space application. Firstly, a thermal cycling degradation model was proposed by considering two physical mechanisms: contamination and fatigue damage. Then, a thermal cycling test scheme of two types of PTRs was designed and performed to demonstrate their long lifetime and high thermal stability. Two type A PTRs with cooling capacity of 1W@60 K and two type B PTRs with cooling capacity of 5W@80 K were continuously operated for about two years in a simulated vacuum thermal cycling environment. Effects of heat rejection temperature variation on thermal stability and dynamic performance of the PTRs were investigated. Furthermore, the thermal cycling degradation model was validated with the actual thermal cycling test data. Finally, the predicted pseudo-failure lifetime was acquired via experimental data and degradation model. Moreover, the estimated reliability of PTRs was obtained through using the Weibull distribution. The proposed thermal cycling test scheme and innovative lifetime prediction and reliability estimation method provide a quick and accurate approach for the cooler manufacturer to assess the lifetime and reliability of the space PTRs.

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