中国物理B ›› 1993, Vol. 2 ›› Issue (7): 544-549.doi: 10.1088/1004-423X/2/7/009

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    

POSITRONIUM EMISSION FROM SURFACE OF Si SUBSTRATES PASSIVATED BY HF ETCHING

何元金, 吴文, 段晓东   

  1. Department of Modern Applied Physics, Tsinghua University, Beijing 100084, China
  • 收稿日期:1992-05-28 出版日期:1993-07-20 发布日期:1993-07-20
  • 基金资助:
    Project supported by the National Natural Science Foundation of China.

POSITRONIUM EMISSION FROM SURFACE OF Si SUBSTRATES PASSIVATED BY HF ETCHING

HE YUAN-JIN (何元金), WU WEN (吴文), DUAN XIAO-DONG (段晓东)   

  1. Department of Modern Applied Physics, Tsinghua University, Beijing 100084, China
  • Received:1992-05-28 Online:1993-07-20 Published:1993-07-20
  • Supported by:
    Project supported by the National Natural Science Foundation of China.

摘要: In order to develop a low-temperature heat-treatment technique for the prepa-ration of Si substrates to be used in-situ in molecular beam epitaxy (MBE), surface defects of the HF etched and passivated substrates were investegated with a slow positron beam analysis, the analysis system was equipped on-line with the molecu-lar beam epitaxy device. The fraction of positronium (Ps) emission from Si surface at different temperatures was estimated by a "peak-method", after comparing with the reflection high energy electron diffraction patterns, it was concluded that for a HF treated specimen a clean and stable passivated surface suitable to MBE can be obtained by an in-situ low-temperature (about 550℃) treatment. However, the pa-rameters of HF treatment (etching time, HF concentration, etc.) should be precisely adjusted in order to avoid the production of excessive damages on Si surfaces.

Abstract: In order to develop a low-temperature heat-treatment technique for the prepa-ration of Si substrates to be used in-situ in molecular beam epitaxy (MBE), surface defects of the HF etched and passivated substrates were investegated with a slow positron beam analysis, the analysis system was equipped on-line with the molecu-lar beam epitaxy device. The fraction of positronium (Ps) emission from Si surface at different temperatures was estimated by a "peak-method", after comparing with the reflection high energy electron diffraction patterns, it was concluded that for a HF treated specimen a clean and stable passivated surface suitable to MBE can be obtained by an in-situ low-temperature (about 550℃) treatment. However, the pa-rameters of HF treatment (etching time, HF concentration, etc.) should be precisely adjusted in order to avoid the production of excessive damages on Si surfaces.

中图分类号:  (Passivation)

  • 81.65.Rv
81.65.Cf (Surface cleaning, etching, patterning) 81.40.Gh (Other heat and thermomechanical treatments) 68.47.Fg (Semiconductor surfaces) 68.35.Dv (Composition, segregation; defects and impurities) 78.70.Bj (Positron annihilation)