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The temperature uniformity of heater plates (HPs) should be sustained due to critical dimension uniformity and robust operation in high temperature processing of 300 mm wafers. It is very challenging to maintain the temperature uniformity of the HP despite the dynamic control of power inputs and temperatures. The packaged power terminals (PPTs) of the HPs may considerably affect their thermal reliability. Hence, the sophisticated thermal modellings and designs of the HPs and the PPTs are necessary. In this study, the finite element analysis (FEA) thermal models of the HP and the PPT were generated, experimentally validated, and employed for the analysis and the design. The influences of the heating element width, the heating element gap, and the zone gap on the thermal performance of the HP were investigated. The parametric influences of the substrate thickness on the thermal performance of the PPT were also explored. The results show that the effect of the heating element width on the temperature of the HP is almost negligible. The results have found that a sophisticated design of the heating elements may reduce the radial temperature difference of the HP by 56 % compared with the baseline case. The results suggest that the sophisticated design may enable both the simplified structure and the enhanced temperature uniformity of the HP.

Accelerated thermal cycling (ATC) tests are conducted for various chip resistor assemblies using the lead-based (SnPb) and lead-free (SnAgCu) solders. The corresponding life prediction models are developed by employing the well-established energy density approach. The life prediction model constants are obtained from the ATC test data. The models are utilized to predict the lifetimes of chip resistor assemblies under a mobile device field condition. The analysis indicates that the lead-free solder used in the chip resistor assembly would offer a longer lifetime under a field condition compared to the lead-based solder regardless of chip resistor types even when a reverse trend is observed in the ATC test results.

High sensitivity shadow moire using non-zero order Talbot distances is proposed. A mathematical description for the contrast of shadow moire fringes produced by broad spectrum light is presented and its validity is corroborated experimentally. Using the non-zero order Talbot distances, the dynamic range is increased substantially and higher measurement sensitivity becomes practical, which has not been possible with the conventional shadow moire using the zero Talbot distance. Contour intervals in the range of 40 to 50 μm per fringe are practical. The critical parameters controlling fringe contrast are discussed and optical configurations for optimum contrast are suggested.