SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To improve gettering efficiency and shorten a thermal treatment time since a method of removing impurity elements such as heavy metal, etc., that is, a gettering technique is very important to obtain a high-performance device, while a treatment time for gettering needs to be shortened in view of a throughput. SOLUTION: It has been found that impurity elements such as heavy metal, etc., segregate in a ridge of a polycrystalline semiconductor layer. To solve this problem, this ridge is positively utilized to form a gettering site for a proximity gettering. When a gettering site utilizing ion doping is further employed together, impurity elements such as heavy metal, etc., can be removed from a TFT channel forming region and a depletion layer region in a PN junction, thereby improving a gettering ability and a gettering efficiency.