SEMICONDUCTOR DEVICE AND ITS PRODUCTION

摘要

PURPOSE:To form high-resistance impurity regions(HRD) with thin-film transistors in source-drain regions in a self-matching manner. CONSTITUTION:A first porous anodically oxidized film 107 is first grown on the side faces of gate electrodes 105 with a low voltage exclusive of a mask 106 atop the gate electrodes 105 and a gate insulating film 104 is etched with these electrodes as a mask. Thereafter, the state that the gate insulating film 104' exists in the regions near the gate electrodes 105 and does not exist in other regions distant from the gate electrode 105 is attained if this anodically oxidized film 107 is selectively etched. An impurity is substantially not doped in the lower part of the gate electrodes 105 and the doping quantity is decreased by the presence of the gate insulating film 104' even in the regions near the gate electrodes 105 and the high-resistance regions 111, 112 of the low impurity concn. are formed if impurity doping is executed in the self-matching manner as the mask of the gate electrode part in this state. The gate insulating film 104' does not exist in the regions distant from the gate electrodes 105 and, therefore, the doping is executed and the low-resistance regions 110, 113 of the high impurity concn. are formed.