GROWTH OF ORIENTED SnO_2 THIN FILMS FROM ORGANOTIN COMPOUNDS ON GLASS SUBSTRATES BY SPRAY PYROLYSIS

摘要

Tin(IV) oxide (SnO_2) is an oxygen-defect type semiconductor with a wide band gap and a large mobility. It is transparent in the visible region, and reflective in the infrared region. Thus, SnO_2 thin films have been used as transparent electrodes in sophisticated electrochromic, electroluminescent, and photoconductive devices. Recently, it has been also reported that gas sensitivity is high for (110) oriented SnO_2 thin flms and a large electrical conductivity is obtained in (200) oriented SnO_2 thin films.rnChemical techniques, including spray pyrolysis using simple apparatus with good productivity, for the preparation of thin films facilitate the design of materials on a molecular level. The influence of preparation conditions on the physical properties of sprayed SnO_2 thin films has been studied extensively; in contrast, the influence on film formation seldom has been examined in detail. Although source compounds play an important role in controlling the structure and morphology of thin films under spray pyrolysis, the effect of those compounds on the growth of thin films has not yet been investigated extensively. In the case of SnO_2 thin films also, other compounds except for tin(IV) chloride1 have not been examined sufficiently.