矽晶片黏合之ＳＯＩ基板及ＭＯＳＦＥＴ之特性探討

Abstract

絕緣矽(Silicon-On-Insulator 簡稱 SOI) 技術是現今半導體技術中 ,最 被看好解決抗輻射線(radiation-hardness)及防止元件鎖住(latch-up)等 效應的方法.而我們即成功的利用矽晶片直接黏合(Silicon Directly Bonding 簡稱 SDB)技術,完成此種基板.以矽晶片直接黏合技術製造SOI基 板的關鍵技術包括:黏合技術,薄化技術與島嶼狀分割技術.在過去,我們已 證明黏合的品質,不管在界面的陷阱密度(Dit),漏電流或崩潰電壓方面,皆 與一般熱氧化成長的SiO2無異.在本文中,我們將探討如何把已黏和好的晶 片薄化,並進一步的了解經薄化後的SOI層,其品質為何.此外,為達成元件 完全隔離的目的,我們亦成功的將SOI層予以島嶼狀的分割.最後,亦是最重 要的,我們成功的在此經薄化且島嶼狀分割後的黏合 SOI層上製造MOSFET, 而後再探討此元件的一些特性.結果,我們證實了SOI- MOSFET在各種特性 上,皆有其優越的表現. Siocon-On-Insulator (SOI) technology is the most promising method to slove the problems of radiation-hardness and latch-up effects. We had successfully accompilished the SOI substrate by using silicon direct bonding (SDB) technology. There are several key points to achieve the desired SOI substrate by using SDB technology, including bonding technology, thinning technology and island-etching technology. In times past , we had successfully demonstrated the bonding qualities of bond- ing qualities of bonding interface trap density (Dit), leakage current and breakdown voltage were as good as that of thermally grown SiO2. In this thesis, we have been investigated how to thin the bonded wafers to a desirable thickness and then what the qualities of the thinned SOI layer are. Finally but most importantly, we have successfully fabrica- ted the MOSFET on the thinned and island-etched SOI layer, and then we investigated some characteristics of this transistor. As a result, we confirmed the electrical characteristics of the SOI- MOSFET is better than the conventional one.