Role of substrate temperature on the properties of microcrystalline silicon thin films

Hydrogenated silicon (Si:H) thin films were deposited in an ultrahigh vacuu m system varying substrate temperature (T-s) from 200 degreesC to 570 degre esC. decomposing a gas mixture of monosilane-hydrogen, by a conventional (1 3.56 MHz) radio frequency plasma enhanced chemical vapor deposition (rf-PEC VD) technique. A compact microcrystalline (muc) Si:H film has been develope d at a deposition rate (R-d) of 25.1 Angstrom min(-1). The structural and b onding configurations were characterized by X-ray diffractometry and infrar ed (IR) vibrational spectroscopy. Growth processes are different for films deposited at low (T-s approximate to 250 degreesC) and high (T-s greater th an or equal to 350 degreesC) temperatures. In the films of low T-s the plan es (111) and (220). and polyhydrides are formed whereas. the growth of crys tallites only along (220) and the monohydride formations are observed for t he films deposited with high T-s The dependence of both structural and opto electronic properties on deposition temperature is discussed in terms of th e growth kinetics and the properties are correlated.