Micro-Raman stress characterization of polycrystalline silicon films grown at high temperature

In this paper the residual stress of polycrystalline silicon (poly-Si) grown at high temperature in a vertical LPCVD reactor has been studied using micro-Raman spectroscopy. The samples were prepared on Si(1 0 0) n-type substrates coated with 100 run Of SiO2. The films were deposited in the temperature range of 750-900 degreesC at pressures of 5 and 10 Torr. The as-deposited poly-Si films are highly crystalline and show tensile stress. Micro-Raman measurements show that the residual stress is reduced as the deposition temperature is increased and, above 800 degreesC, tensile stress is reduced to less than 150 MPa. These results indicate that high quality, high crystalline and low strained poly-Si films can be obtained in this type of reactor using higher deposition temperature. (C) 2004 Elsevier B.V. All rights reserved.