DIRECT OBSERVATION OF CHANNEL-DOPING-DEPENDENT REVERSE SHORT-CHANNEL EFFECT USING DECOUPLED C-V TECHNIQUE

Abstract

A non-destructive high resolution ''Decoupled C-V Technique'' for small geometry devices has been developed and demonstrated to successfully extract the intrinsic channel capacitance of submicron metal-oxide-semiconductor field effect transistors (MOSFET's). The effective channel doping concentration calculated from the extracted intrinsic gate capacitance presents an obvious dopant concentration enhancement in the intrinsic channel region of submicron devices compared to that of long channel devices, as the channel implant dose increases beyond a critical value. The anomalous reverse short channel effect i.e. threshold voltage increases with channel length scaled down, is simultaneously observed on the heavily doped short channel devices. The self-consistency between the C-V and I-V measurement supports that the reverse short channel effect apparent in the submicron CMOS technology is due to the channel dopant enhancement induced by high dose channel implants for both N-channel and P-channel devices.