High-Performance P-Type Germanium Tri-Gate FETs via Green Nanosecond Laser Crystallization and Counter Doping for Monolithic 3-D ICs

Hao Tung Chung, Yu Ming Pan, Nein Chih Lin, Bo Jheng Shih, Chih Chao Yang, Chang Hong Shen, Huang Chung Cheng, Kuan Neng Chen*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

This paper proposed a fabrication of p-type Germanium (Ge) tri-gate field-effect transistors (Tri-gate FETs) via green nanosecond laser crystallization (GNSLC) and counter doping (CD). By using the GNSLC, the nano-crystalline-Ge (nc-Ge) with a grain size of 80 nm could be turned into polycrystalline Ge (poly-Ge) with that of above 1 μm. With the increase of laser power, the improved crystallinity and lower hole concentration of poly-Ge were also verified by Raman spectra and Hall measurement. To fabricate the high-performance Ge Tri-gate FETs, the chemical-mechanical planarization (CMP) and counter doping (CD) process would further be utilized. The CMP process eliminated the surface roughness of poly-Ge while the CD process decreased the hole concentration of poly-Ge or even converted that into an N-type one. The effect of the CD on the performance of p-type Ge Tri-gate FETs was further investigated. Consequently, the GNSLC Ge Tri-gate FETs showed threshold voltage (Vth) of-0.41 V, ION of 7.10×10-6, and IOFF of 1.28×10-9 respectively, indicating better crystallinity of the Ge channel.

Original languageEnglish
Pages (from-to)262-268
Number of pages7
JournalIEEE Journal of the Electron Devices Society
Volume11
DOIs
StatePublished - 2023

Keywords

  • counter doping (CD)
  • green nanosecond laser crystallization (GNSLC)
  • Monolithic 3D integration
  • polycrystalline Ge (poly-Ge)
  • tri-gate field-effect transistors (Tri-gate FETs)

Fingerprint

Dive into the research topics of 'High-Performance P-Type Germanium Tri-Gate FETs via Green Nanosecond Laser Crystallization and Counter Doping for Monolithic 3-D ICs'. Together they form a unique fingerprint.

Cite this