Semiconductor devices are built using hyperpure silicon and very controlled levels of doping to create desired electrical properties. Contamination can alter these precisely controlled electrical properties that can render the device non-functional or unreliable. It is desirable to determine what impurities impact the device and control them. This study consists of four parts: a) determination of acceptable SCI (Standard Clean 1) bath contamination levels using VPD-DSE-GFAAS (Vapor Phase Decomposition Droplet Surface Etching Graphite Furnace Atomic Absorption Spectroscopy), b) copper deposition from various aqueous HF solutions, c) anion contamination from fluoropolymers used in chemical handling and d) metallic contamination from fluoropolymers and polyethylene used in chemical handling. A technique was developed for the determination of metals on a silicon wafer source at low levels. These levels were then correlated to contamination levels in a SCI bath. This correlation permits the determination of maximum permissible solution contaminant levels. Copper contamination is a concern for depositing on the wafer surface from hydrofluoric acid solutions. The relationship between copper concentration on the wafer surface and hydrofluoric acid concentration was determined. An inverse relationship exists and was explained by differences in diffusion rates between the differing copper species existing in aqueous hydrofluoric acid solutions. Finally, …

The Sn/Pb eutectic alloy system is the most widely used joining material in the electronics industry. In this application, the solder acts as both an electrical and mechanical connection within and among the different packaging levels in an electronic device. Recent advances in packaging technologies, however, driven by the desire for miniaturization and increased circuit speed, result in severe operating conditions for the solder connection. In an effort to improve its mechanical integrity, metallic or intermetallic particles have been added to eutectic Sn/Pb solder, and termed composite solders. It was the goal of this study to investigate the growth and morphology of the two intermetallic phases (Cu6Sn5 and Cu3Sn) that form between a Cu substrate and Sn/Pb solder under different aging and annealing conditions.