The chemical bonding state and surface morphology of sulfuric-vapor treated GaAs surface were investigated using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The sulfuric vapor was obtained through the heating of (NH4)2Sx solution at 60 °C. At the initial state of the treatment, the decrease of elemental As and the generation of As-S bonds were observed. Even after all of the elemental As converted into As-S bonds, peak area of the As-S bond increased until 5 min exposure. Unlike the liquid-phase treatment, the dissolution of the elemental As did not happen during the treatment and the formation of As-polysulfides was observed. Through the surface treatment of the GaAs using sulfuric vapor, small particles were formed and increased with treatment time. After 5 min exposure, they were linked to form a large agglomerate. This corresponds to a deposit of polysulfides containing hydrogen. To evaluate the effectiveness of the sulfuric vapor-treatment against oxidation in air, the treated GaAs was exposed to air and compared with the GaAs treated using a (NH4)2Sx solution. The As-polysulfides and polysulfides containing hydrogen were revealed to be easily decomposed by exposure to air. The character of S bond with GaAs was revealed to be the most important to obtain a passivation effect.
|Number of pages||7|
|Journal||Thin Solid Films|
|Publication status||Published - 1999 Nov 1|
|Event||Proceedings of the 1999 26th International Conference on Metallurgic Coatings and Thin Films - San Diego, CA, USA|
Duration: 1999 Apr 12 → 1999 Apr 15
Bibliographical noteFunding Information:
The authors wish to acknowledge the financial support of the Korea Research Foundation made in the program year 1998.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry