| 摘要 |
PURPOSE:To measure without contact a device under normal function, by keeping the irradiation rate of laser irradiation to areas of which circuit activity is changeable, or irradiation rate during a period in which circuit activity is changeable, or both above irradiation rates under a certain level. CONSTITUTION:When conditions which specify certain areas 31, 32 are input 19, by position information, laser irradiation control circuit 20 gives a signal based on scanning position information from laser scanning and picture indicating control unit 16, thus opening and closing light switch 18. As a result, irradiation of the beam is shut out from specific areas 31 and 32 of sample IC 5, preventing malfunction of the sample. Inspection of this area can be done by a buffer circuit which hardly malfunctions or by connected gate circuit, etc. And, light switch is turned off to stop laser scanning during the period with possibility of malfunction caused by laser beam irradiation. By using this type of laser scanning microscope, normal function of the semiconductor device can be guaranteed, and logical level of the inside circuit, etc. can be measured without contact. |
