The success of printing technology in the electronics industry primarily depends on the availability of metal printing ink. Various types of commercially available metal ink are widely used in different industries such as the solar cell, radio frequency identification (RFID) and light emitting diode (LED) industries, with limited usage in semiconductor packaging. The use of printed ink in semiconductor IC packaging is limited by several factors such as poor electrical performance and mechanical strength. Poor adhesion of the printed metal track to the epoxy molding compound is another critical factor that has caused a decline in interest in the application of printing technology to the semiconductor industry. In this study, two different groups of adhesion promoters, based on metal and polymer groups, were used to promote adhesion between the printed ink and the epoxy molding substrate. The experimental data show that silver ink with a metal oxide adhesion promoter adheres better than silver ink with a polymer adhesion promoter. This result can be explained by the hydroxyl bonding between the metal oxide promoter and the silane grouping agent on the epoxy substrate, which contributes a greater adhesion strength compared to the polymer adhesion promoter. Hypotheses of the physical and chemical functions of both adhesion promoters are described in detail.

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In wafer foundry it is important to make use of reliability monitoring strategy as part of process monitoring. A fast reliability monitoring strategy has been developed, which enables a fast feedback to the production line. The three main critical reliability failure mechanisms associated with the CMOS device are hot carrier effects, gate oxide breakdown and electromigration. The fast Wafer level reliability (WLR) methodology was employed for monitoring of the critical reliability failure mechanisms in the wafer fab. Using substrate current measurement as monitoring parameter for hot carrier effects, accelerated testing for electro migration and monitoring gate oxide integrity through standard production tests, the new methodology has proved to help the fab decrease test time while increasing monitoring frequency.

A critical examination is made of the concept that gear scoring occurs when the EHD film thickness is less than several times the combined surface roughness. The well known experimental data of Borsoff, Borsoff and Godet, and Ku and Baber is analyzed using advanced EHD computational techniques. The study finds: (a) Gear scoring occurs under fully boundary-lubricated conditions and not even close to the breakdown of the EHD film. (b) Isothermal calculations of minimum EHD film thickness are in error both in magnitude and in trend with failure velocity. An analysis which takes thermal effects into account must be used. (c) Pitch point EHD film thickness does not reliably represent minimum EHD film thickness and therefore cannot be substituted for it. (d) The peak Hertz contact stress in a gear mesh may be significantly understated if calculated only at the pitch point.