Wafer Defects Issue Study In Wet Etch And Wet Clean

Under the guidance of Moore’s Law, the semiconductor industry onto a new level every two to three years. Huge capital investment, higher technical engineer usage than average proportion of the industrial sector, which led to the semiconductor manufacturing high cost sharing, coupled with fierce competition make product prices continued to decline, it drives most of the chip manufacturing operate in a large-scale production and high yield levels. Maintaining and improving yield of the semiconductor industry is essential, a high level of process yield is the key factor to the reliable performance of chip and the proceeds.The important aspect of inhibit yield is that the defective wafers are generally beyond repair. In some cases, the defective wafer is to downgrade and do low-end applications. The scrapped wafer can be used as control wafer, these defects from different kinds of liquids, gases, clean room air, personnel, process, equipment and water in wafer production areas. Particles and other small contaminants stay in the internal or surface of the wafer, make it suffer surface contamination or form irregular isolated area. Many defects are generated in lithography, so solving the problem of lithography wafer defect has great significance to improve the chip yield.Firstly, giving a simple overview of microelectronics, integrated circuits and the basic process of semiconductor manufacturing, then introducing the basic process of wet etch and clean and the desired material of wet etch and clean including etch chemical,clean chemical, DI water, IPA, wet etch tools. Most wafer defects have relationship with wet etch tools. So this paper focuses on the structure and working principle of wet etch tools.This paper based on the actual production of wet etch defects issue, studied Poly residue defects, PR residue defects, wafer center thickness abnormal defect, EPI film hole defects, ball defects in depth and analysis of the factors that cause wafer defects, found out a viable solution through experiments, reduced the product rework and scrap rates, and improved the production efficiency.