用于TFT有源层的Ar~+激光结晶a-Si:H的性质(英文)

Properties of Ar~+ Laser Crystallized a-Si:H for Active Layer of TFT

This paper demonstrates the technological approach to the high performance a-Si:H thin film transistor (TFT) fabricated by the Ar+ laser-crystallization technique on the fused quartz substrates. The a-Si:H films for the active layer of TFT were prepared in a capacitively coupled glow-discharge deposition system. The films were crystallized by CW Ar+ laser scanning at low speeds (3-5 cm/s). The laser power ranges from 2.5W to 5.0W. The TEM cross-section micrograph illustrates that a liquid phase laser crystallization region (LP-LCR) has defect-free of structure with a grain size of the order of handreds of micron. In the Raman spectrum of LP-LCR, 475 cm-1 peak of a-Si:H disappears and 520 cm-1 peak of c-Si becomes stronger and sharper. The value of conductivity in the layer of LP-LCR is five orders of magnitude larger than the one in asepositedd a-Si:H film. We also discussed some problems to be overcome in application of a-Si : H TFTs in LCD.