| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce contamination impurities in a semiconductor and an insulation film interface in contact with it by removing contamination impurities in a first film surface, thereafter forming a second film thereon, and making impurity concentration in an interface within a specified value. SOLUTION: An amorphous semiconductor film 150 is formed 50 nm thick typically. A crystalline semiconductor film 151 formed in a crystallization process is formed to a first island-like semiconductor film 105 and a second island- like semiconductor film 104 by a dry etching method by forming a resist mask using a first photomask. Contamination impurities 155 existing in a surface of the films are removed by scattering fluorine containing acid solution by dropping and bringing it into contact with a film surface. A gate insulation film 106 mainly composed of silicon oxide, etc., is formed in a surface of the first semiconductor film 105 and the second semiconductor film 104 wherein the contamination impurities 155 are removed. The contaminant concentration of an interface can be made within 2×10 atoms/cm3 by forming a gate insulation film 106 as soon as the contamination impurities 155 are removed.</p> |
