US 6,982,213 B2
Method of manufacturing a semiconductor device by irradiating with a laser beam
Setsuo Nakajima, Atsugi (Japan); Aiko Shiga, Atsugi (Japan); Naoki Makita, Osaka (Japan); and Takuya Matsuo, Osaka (Japan)
Assigned to Semiconductor Energy Laboratory Co., Ltd., Kanagawa-ken (Japan); and Sharp Kabushiki Kaisha, Osaka (Japan)
Filed on Apr. 29, 2002, as Appl. No. 10/133,588.
Claims priority of application No. 2001-148635 (JP), filed on May 18, 2001.
Prior Publication US 2002/0173085 A1, Nov. 21, 2002
Int. Cl. H01L 21/20 (2006.01)
U.S. Cl. 438—486 9 Claims
OG exemplary drawing
 
1. A method of manufacturing a semiconductor device, said method comprising the steps of:
forming an amorphous semiconductor film over a substrate;
introducing a metallic element into the amorphous semiconductor film;
forming a first crystalline semiconductor film by heating the amorphous semiconductor film;
removing an oxide film formed on a surface of the first crystalline semiconductor film;
forming a clean oxide film on the first crystalline semiconductor film by spraying ozone water;
forming a second crystalline semiconductor film by irradiating the first crystalline semiconductor film with a laser beam in an inert gas atmosphere.