N. Matsuki, R. Maruyama, S. Yasuda, H. Koinuma*

Ceramics Materials and Structures Laboratory / Tokyo Institute of Technology
4259 Nagatsuta, Midori-ku, Yokohama 226, Japan
koinuma@oxide.rlem.titech.ac.jp

*also CREST, JST

The first combinatorial approach to plasma chemical processes was applied to the fabrication of hydrogenated amorphous silicon (a-Si:H) and alloys (a-SiC, a-SiN, etc) as well as of their multi-layer structures.

The key-point for the combinatorial plasma CVD and nitridation is the use of physical masks placed on or above the substrate. Our first study was performed as follows. First, phosphin doped a-Si:H films were deposited on a glass substrate in the slit (5 x 60mm2) region of a moving mask by the plasma CVD of source gas mixture (PH3/SiH4), in which PH3 concentration was increased in m steps. Thus, we could control P concentration in the deposition of P-doped a-Si:H films along x-axis. Then, the second plasma treatment, nitrization, was done by moving the mask in n steps with the slit along y-axis to produce m x n different a-SiN:H/ P-doped a-Si:H bi-layer films. These bi-layer films are examined for the use of TFT and field effect devices including the field effect solar cell we are proposing[1].

[1] Koinuma, H.Fujioka, C.Hu, T.Koida, M.Kawasaki, Mat. Res. Soc., Symp. Proc., 426 (1996) 95