以低溫微波活化鍺薄膜摻雜之研究

Abstract

本論文為利用微波退火製程來活化多晶鍺薄膜中的離子佈植摻雜物，可抑止摻雜物擴散。對於經過離子佈植後產生的非結晶區域，發現薄膜的電阻率高對於微波的吸收率較高。而薄膜的厚度也對於微波的吸收率有影響。我們嘗試以不同的微波強度及時間施加於鍺薄膜，藉由量測其片電阻值進而推算電阻率，觀察其活化的程度。我們發現縮短微波製程的時間可以控制雜質擴散，減少晶圓在高溫的環境。而在晶圓上下加入空白矽晶圓可以降低製程初始的升溫速率，此一作用同樣對於減少雜質擴散及保護晶圓表面有一定的幫助。利用微波退火的低溫活化特性，可防止鍺薄膜中離子佈子摻雜物發生擴散的現象及避免金屬污染，減少製程的步驟。在未來將可應用於元件微縮。

We study on the microwave annealing process to activate boron and phosphorus in single and poly germanium thin film. The amorphous thin film on the wafer was formed by ion implantation. The higher resistivity of the thin film has the better fraction of microwave absorption. And the film thickness also influences the microwave absorption. The wafers go through different microwave power and process time to observe dopant diffusion. We found to decrease the process time, shorten the wafer stay in the near-maximum temperature of the process, can reduce the dopant diffusion. And the addition of filler wafers above and below the wafer can also suppress the dopant diffusion and prevent the damage on the wafer surface.