Photo-induced volume changes in a-Si : H films prepared by Cat-CVD method

Photo-induced volume changes in a-Si:H films prepared by the catalytic chem ical vapor deposition (Cat-CVD) method have been studied, The investigated a-Si:H films have an initial stress P-i of tensile from similar to - 150 to similar to -350 MPa. Some a-Si:H films with P-i < -200 MPa exhibit the con traction of volume change, the li.-ht-induced contraction, due to the Ar io n laser light illumination of 200 mW/cm(2). The correlation between the pho to-induced volume changes and the initial stress is discussed from the view point of the initial structure of the film, comparing the data of the photo -induced volume change in a-Si:H films prepared by the conventional plasma enhanced chemical vapor deposition (PECVD) method. (C) 2001 Elsevier Scienc e B.V. All rights reserved.