Novel Source Heterojunction Structures with Relaxed-/Strained-Layers for Quasi-Ballistic CMOS Transistors

• Published in: Key engineering materials 2011-01, Vol.470, p.72-78
• Main Authors: Hasegawa, Mitsuo, Sameshima, Toshiyuki, Mizuno, Tomohisa
• Format: Article
• Language: English
• Subjects: CMOS; Devices; Heterojunctions; Ion implantation; Semiconductors; Shot; Silicon germanides; Transistors
• ISSN: 1013-9826; 1662-9795; 1662-9795
• DOI: 10.4028/www.scientific.net/KEM.470.72

We have studied new abrupt-source-relaxed/strained semiconductor-heterojunction structures for quasi-ballistic complementary-metal-oxide-semiconductor (CMOS) devices, by locally controlling the strain of a single strained semiconductor. Appling O+ ion implantation recoil energy to the strained semiconductor/buried oxide interface, Raman analysis of the strained layers indicates that we have successfully relaxed both strained-Si-on-insulator (SSOI) substrates for n-MOS and SiGe-on-insulator (SGOI) substrates for p-MOS without poly crystallizing the semiconductor layers, by optimizing O+ ion implantation conditions. As a result, it is considered that the source conduction and valence band offsets EC and EV can be realized by the energy difference in the source Si/channel-strained Si and the source-relaxed SiGe/channel-strained SiGe layers, respectively. The device simulator, considering the tunneling effects at the source heterojunction, shows that the transconductance of sub-10 nm source heterojunction MOS transistors (SHOT) continues to increase with increasing EC. Therefore, SHOT structures with the novel source heterojunction are very promising for future quasi-ballistic CMOS devices.