Si/Ge MOSFET and SiGe HBT Devices

The superior transport property of Ge can reach high performance target in the future CMOS technology. The high mobility and compatibility with CMOS process make Ge a promising material in the future high-end device application even though there are still some unresolved issues such as the cost and unstable germanium oxide dielectrics.


In this project, we focus on developing the low cost, high performance Ge MOSFETs, which is expected to replace silicon as the future industry mainstream. Many technical solutions such as Ge surface passivation, high K-metal gate (HK-MG) and strain engineering are applied to boost the channel mobility and enhance the device performance and stability. In 2010, we successfully demonstrated the world highest mobility Ge NFETs on (001) Ge substrate (published on IEDM 2010). The record peak mobility of ~1050 cm2/V-s is the highest reported electron mobility on (001) Ge from now. On the other side, the new thermal growth technique of thin film Ge/SiGe on Si wafers is promoted recently. Ge-on-Si material structure can provide Ge MOSFET a cheap and high strained substrate layer.



2010 IEDM Ge nMOSFET device



Peak mobility: ~1050 cm2/V-s

The SS value: 150mV/dec

Device on/off ratio: 2x104.

Junction, on/off ratio: 2x105



2011 IEDM SOI based Ge GAA PFETs

Weff/Lg (nm) =260/183

Wfin = 52nm

Ion/Ioff ~ 1´105

EOT = 5.5nm

S.S = 130 mV/dec

2012 IEDM Triangular Ge NFETs on Si with (111) Sidewalls 


EOT=0.39 nm  ZrO2/Ge


Weff/Lg (nm) =186/350

Wfin = 58nm

Ion/Ioff ~ 1´104

EOT = 5.5nm

S.S = 94 mV/dec

Ion: 2 times enhanced





Related Publication:

  1. Shu-Han Hsu, Hung-Chih Chang, Chun-Lin Chu, Yen-Ting Chen,Wen-Hsien Tu, Fu Ju Hou, Chih Hung Lo, Po-Jung Sung, Bo-Yuan Chen, Guo-Wei Huang, Guang-Li Luo, C. W. Liu, Chenming Hu, and Fu-Liang Yang, Triangular-channel Ge NFETs on Si with (111) Sidewall-Enhanced Ion and Nearly Defect-free Channels,” accepted International Electron Devices Meeting (IEDM), 2012.
  2. Shu-Han Hsu, Chun-Lin Chu, Wen-Hsien Tu, Yen-Chun Fu, Po-Jung Sung, Hung-Chih Chang, Yen-Ting Chen, Li-Yaw Cho, Guang-Li Luo, William Hsu, C. W. Liu, Chenming Hu, and Fu-Liang Yang, Chenming Hu, and Fu-Liang Yang, Nearly Defect-free Ge Gate-All-Around FETs on Si Substrates,”  International Electron Devices Meeting (IEDM), 2011. 
  3. Yen Chun Fu, William Hsu, Yen-Ting Chen, Huang-Siang Lan, Cheng-Han Lee, Hung-Chih Chang, Hou-Yun Lee, Guang-Li Luo, Chao-Hsin Chien, C. W. Liu, Chenming Hu, and Fu-Liang Yang " High mobility high on/off ratio C-V dispersion-free Ge n-MOSFETs and their strain response," International Electron Devices Meeting (IEDM), 2010.