Patent ID: 9257288
Filing Date: 2016-02-09
CPC Classification: H01L

Claim Text:
1. A method of manufacturing a thin film transistor (TFT), the method comprising: irradiating light from a light source onto a monitoring amorphous silicon (a-Si) thin film to anneal the monitoring a-Si thin film and concurrently measuring a Raman scattering spectrum of light irradiated from the light source and scattered by the monitoring a-Si thin film; calculating a crystallization characteristic value of the monitoring a-Si thin film based on the Raman scattering spectrum; and manufacturing a polycrystalline silicon (poly-Si) TFT by preparing an a-Si thin film using conditions the same as those used for the monitoring a-Si thin film when the crystallization characteristic value matches a reference characteristic value, wherein the measuring of the Raman scattering spectrum of the light irradiated from the light source and scattered by the monitoring a-Si thin film is performed at set time intervals, and wherein the calculating of the crystallization characteristic value of the monitoring a-Si thin film comprises: calculating a peak ratio between an amorphous Si peak and a polycrystalline Si peak from the Raman scattering spectrum at each of the time intervals; plotting the peak ratios to form a peak ratio pattern graph; and calculating an attenuation parameter value of an exponential decay formula as the crystallization characteristic value by using the peak ratio pattern graph.