Title :
The optical and electrical characteristics of a-Si:H films prepared by ECR CVD
Author :
Kang, Moonsang ; Kim, Jaeyeong ; An, Chul ; Lim, Taehoon ; Oh, Onhwan ; Jeon, Bupju ; Jung, Ilhyun ; Koo, Yongseo
Author_Institution :
Dept. of Electr. Eng., Sogang Univ., Seoul, South Korea
Abstract :
The optical and electrical properties of hydrogenated amorphous silicon films, deposited by ECR plasma CVD, were investigated as a function of H2/SiH4 ratio and as a function of substrate temperature. Photoconductivity increased with increasing SiH 4 gas content or with increasing substrate temperature, due to the decrease of optical band gap, FWHM and the ratio of the concentration of dihydride to that of monohydride. Dark conductivity decreased with increasing substrate temperature due to the increase of surface roughness, and was quite independent of H2/SiH4 ratio. The influence factors of photoconductivity were hydride bonding configuration, optical band gap and FWHM. The dominant factor of dark conductivity was the surface roughness
Keywords :
Raman spectra; amorphous semiconductors; atomic force microscopy; bonds (chemical); dark conductivity; elemental semiconductors; energy gap; hydrogen; infrared spectra; optical constants; photoconductivity; plasma CVD coatings; semiconductor thin films; silicon; surface topography; AFM; ECR plasma CVD; FWHM; H2; H2/SiH4 ratio; Raman spectroscopy; Si:H; SiH4; a-Si:H films; dark conductivity; dihydride to monohydride concentration ratio; electrical characteristics; hydride bonding configuration; optical absorption spectra; optical band gap; optical characteristics; photoconductivity; substrate temperature; surface roughness; Amorphous silicon; Conductivity; Electric variables; Optical films; Photoconductivity; Photonic band gap; Plasma properties; Plasma temperature; Rough surfaces; Surface roughness;
Conference_Titel :
Optoelectronic and Microelectronic Materials And Devices Proceedings, 1996 Conference on
Conference_Location :
Canberra, ACT
Print_ISBN :
0-7803-3374-8
DOI :
10.1109/COMMAD.1996.610171
