AVS 51st International Symposium
    Thin Films Monday Sessions
       Session TF-MoP

Paper TF-MoP20
Strained Si n-channel Metal-oxide-semiconductor Transistor on Relaxed SiGe Film with an Intermediate Si:C Layer

Monday, November 15, 2004, 5:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: S.-W. Lee, National Tsing Hua University, Taiwan
Authors: S.-W. Lee, National Tsing Hua University, Taiwan
P.S. Chen, Industrial Technology Research Institute, Taiwan
Y.L. Chieh, National Tsing Hua University, Taiwan
M.-J. Tsai, Industrial Technology Research Institute, Taiwan
C.W. Liu, Industrial Technology Research Institute, Taiwan
L.J. Chen, National Tsing Hua University, Taiwan
Correspondent: Click to Email
An intermediate Si:C layer in the SiGe film, replacing the conventionally graded buffer layer, was used to form the high-quality relaxed SiGe substrate. With the 700-nm-thick SiGe overlayer, such a SiGe/Si:C/SiGe heterostructure has a threading dislocation density of 5.5x10@super5@ cm@super-2@ and a degree of strain relaxation of 98%. From the TEM observation, the numerous misfit dislocations were formed and confined at the top interface of SiGe/Si:C, maintaining a defect-free SiGe overlayer. Strained-Si n-channel metal-oxide-semiconductor transistors using this relaxed SiGe substrate were fabricated and their characteristics were examined. The effective mobility of the strained-Si device exhibits an enhancement of roughly 90% over that of Si control device at a given effective field. This work provides a simple method for the formation of strained Si layers.