Backend Wet Etch Chemistry And Its Cost Study For IC Process

The rapid development of IOT and AI promotes IC extensive application and usage;IC chips have become China's NO.1 import products.Integrated circuit has been China national development strategy.IC Chips manufacturing is a high-tech industry,which need high investment but also can get high return.The chemistry which used in IC process,especially the solvent chemistry which used in backend process,expensive and components confidential,these advanced chemistries are dominated by foreigner chemical companies.This project relies on 12 inch wafer with 65 nm process,study backend wet clean chemistry characteristics,clean methodology and parameter control,then try to develop a new chemistry to replace the original chemical,get the purpose to reduce cost,get rid of monopoly and improve engineers skills for wafer cleaning process.The study starts with analysis of etch by-products and photo resist,focus on by-products and PR structures/characteristics,also analyzes current cleaning chemical-A function,understand chemical-A components,do research,study each components function during cleaning process,then create a proposal of using new chemistry to replace chemical-A,use theory method to demonstrate the represent cleaning function first,then use experiment and DOE to execute clarification,collecting offline data and inline date to prove the feasibility of proposal B.The test results show that the new chemical-B can fully achieve Chemical-A cleaning efficiency,the product verification results also meet the requirements.Design the cost analysis model for new proposal;Initial the feasibility report,get company approval for new proposal.Use company existing facility system,build new chemical-B on site blending and delivery system,meanwhile,set down chemical control system,Execute SQL Pathfinder software to automatic get data from system,use JMP software to show chemical usage trend chart,real-time monitoring and feedback chemical-B usage.The actual production shows that chemical-B make huge cost reduction,the real cost reduce to 20% of original spending,which saves hundreds of thousands of dollars each year for company.This project also provides theoretical basis for subsequent research.