STRUCTURE OF THIN-FILM TRANSISTOR AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A thin film transistor structure and a method for manufacturing the same is provided to form the second gate on n- region out of drain regions(n+ - n- - n+) to reduce the off current while increasing on current. CONSTITUTION: The thin film transistor structure includes a silicon layer(21), the first impurity layer(24), the second impurity layer, an oxide layer(22) and the first and second gates. The silicon layer and the first impurity layer are formed on an insulator layer with a predetermined spacing between them. The second impurity layer is formed between and around the contact portion of the silicon layer and the first impurity layer. The oxide layer is raised on the silicon layer and the first impurity layer to form the first and second gates. The concentration of the first impurity layer is lower than that of the second impurity layer.