Hydrogenation for PolySilicon MOSFET's by ion shower doping technique

Abstract

Hydrogenation using the ion shower doping technique has been proposed as a means of improving the ON/OFF ratio of both p-channel and n-channel polysilicon MOSFET's constructed with LPCVD polysilicon films. Hydrogen ions accelerated at a voltage as low as 0.5-2.0 kV have been doped on heated MOSFET's in the presence of an interdielectric layer and AI electrode. Our ion shower doping of 30 min at 470°C with a subsequent anneal of 30 min has improved drive and leakage current by two orders of magnitude and by one order of magnitude, respectively, on both p- and n-channel MOSFET's.