AVS 59th Annual International Symposium and Exhibition
    Plasma Science and Technology Thursday Sessions
       Session PS-ThP

Paper PS-ThP34
No- Residue and High- Rate Etching of InGaAs by High Density Plasma

Thursday, November 1, 2012, 6:00 pm, Room Central Hall

Session: Plasma Science and Technology Poster Session
Presenter: Y. Ohsawa, Tokyo Electron Technology Center, America, LLC
Authors: Y. Ohsawa, Tokyo Electron Technology Center, America, LLC
H. Nakajima, Tokyo Electron America
T. Nishizuka, Tokyo Electron America
M. Takahashi, Tokyo Electron America
Y. Trickett, Tokyo Electron Technology Center, America, LLC
G. Nakamura, Tokyo Electron Technology Center, America, LLC
A. Ko, Tokyo Electron Technology Center, America, LLC
H. Ohtake, Tokyo Electron Technology Development Institute, INC., Japan
C. Huffman, SEMATECH
R. Hill, SEMATECH
Correspondent: Click to Email
III-V materials are promising candidates for the channel materials beyond 10 nm generation of CMOS-logic devices. Among them, InGaAs was one of the best materials for NFET channel because of the high electron mobility. However, there are few reports of InGaAs etching. Previous reports showed that the problems were the residue of Indium and low etching rate. Because these issues came from the low reaction between the InGaAs surface and radicals, we have to enhance the surface reaction.In this paper, the precise InGaAs etching was investigated by high electron density (high Ne)/ low electron temperature (low Te) plasma with hot stage operation to improve the issue of residue and low rate. We used RLSATM Etch tool as an InGaAs etcher. This tool has high Ne of more than 1×1011cm-3 and low Te of less than 1 eV around the stage because RLSATM Etch tool uses the surface wave plasma and diffusion chamber. A selection of gas chemistry and temperature was optimized to enable the proper plasma reactivity with Indium without creating residues. High rate of more than 100nm/ min was obtained without Indium residue. Since the reaction of Indium- methyl radical are enhanced by more than 150 oC, it was considered that the etching reaction was enhanced by hot stage. In addition, the re-deposition of by-products was reduced because of low electron temperature. Based on additional analytical investigations, we found that the combination of high Ne- low Te plasma and hot stage is one of the best solution for no-residue and high rate etching of InGaAs.