| 摘要 |
PROBLEM TO BE SOLVED: To establish a method for evaluating defects in thin films and poor- dielectric strength areas in a semiconductor device. SOLUTION: A semiconductor device, composed of a silicon substrate 1, a gate oxide film 2 containing a defect 3 and a poor-dielectric strength area 4, and a polysilicon film 5, formed in this order, is immersed in chemical etchant 7 filled in a wet etching system 9. Chemical etching is performed with the silicon substrate 1 used as an anode and voltage applied by means of a direct- current voltage power supply 6 provided on the wet etching system 9. A passivation layer 10 is formed on the surface of the polysilicon film 5 in the positions at which the defect 3 or poor-dielectric strength area 4 is present, and no passivation layer 10 is formed on the surface of the polysilicon film 5 in the positions at which insulation is provided by the gate oxide film 2. The polysilicon film 5 in the regions where no passivation layer 10 has been formed is removed by the chemical etchant 7. |
