A technique to grow a number of materials on a single substrate using a phy
sical mask in a hot wire chemical vapor deposition (HWCVD) system is develo
ped. Using this technique, we examine materials continuously varying from a
morphous to microcrystalline silicon as we vary the hydrogen-to-silane gas
ratio from 0 to 20 at a substrate temperature of about 250 degrees C. Raman
and reflectance spectra clearly show that the material structure changes r
apidly at a ratio of 2 to 4. The results indicate that the near-transition
materials still retain optoelectronic properties similar to amorphous silic
on. (C) 1999 Elsevier Science Ltd. All rights reserved.