AVS 45th International Symposium
    Manufacturing Science and Technology Group Wednesday Sessions
       Session MS-WeM

Paper MS-WeM8
Studies of 300MM Poly-Silicon Etch Processes Using A Inductively Coupled Plasma Source

Wednesday, November 4, 1998, 10:40 am, Room 317

Session: Advanced Process Equipment and ES&H
Presenter: T. Ni, Lam Research Corp.
Authors: T. Ni, Lam Research Corp.
W. Collison, Lam Research Corp.
K. Takeshita, Lam Research Corp., Japan
Correspondent: Click to Email
Inductively-coupled plasma sources have been successfully applied to 200mm poly-silicon wafer etch processes. As semiconductor wafer size increases from 200mm to 300mm, scaling up sources to meet the same or even more stringent requirements is very challenging. In this study, a transformer coupled plasma (TCP) chamber is designed and studied for 300mm poly-silicon etch processes. Plasma simulation and Langmuir probe were used to investigate the effects of TCP power, chamber pressure, aspect ratio , and coil configuration on plasma uniformity. As a result, plasma uniformity is optimized from 5mTorr to 80mTorr. Effects of different gas injection schemes are carefully examined. It is found that gas injection has strong impact on etch uniformity and profile. A unique gas injector is designed to deliver gas efficiently and minimize profile microloading. A TCP coil is constructed to provide uniform plasma and uniform etch rate. Large conductance of the chamber allows high flow processes. Advanced control systems are implemented to improve process repeatability, minimize chamber-to-chamber variation, and increase throughput. Excellent etch results and wide process window were achieved. Detailed etch process results will be presented and discussed.