Patent ID: 6743667
Filing Date: 2004-06-01
Classification: H01L

Abstract:
A method of manufacturing an active matrix type device, said method comprising the steps of:introducing a material for promoting crystallization of silicon into an amorphous semiconductor film comprising silicon; crystallizing the amorphous semiconductor film to form a crystalline semiconductor film; forming at least a semiconductor island by patterning the crystalline semiconductor film, said semiconductor island including a channel region therein; selectively introducing phosphorus into a part of the semiconductor island in order to form a pair of light doped regions, a source region and a drain region; wherein the source region and the drain region are rendered amorphous while the channel region remains crystalline; wherein one of the light doped regions is formed between the source region and the channel region while the other of the light doped regions is formed between the drain region and the channel region; annealing the semiconductor island to diffuse the material from the channel region where the phosphorus has not been introduced toward the source region and the drain region where the phosphorus has been introduced through the pair of light doped regions; irradiating the semiconductor island with a light, wherein a first concentration of phosphorus in the source region and the drain region is higher than a second concentration of the material in the channel region after the step of annealing the semiconductor island to diffuse the material, wherein each of the source region and the drain region comprises phosphorus at a concentration in a range of 1Ã—1020 to 2Ã—1021 cmâˆ’3, and each of the pair of light doped regions comprises phosphorus at a concentration in a range of 1Ã—1017 to 2Ã—1018 cmâˆ’3.