| 摘要 |
PURPOSE:To make it possible to measure the concentration of an impurity such as oxygen in a desired minute region, while eliminating the interference due to the multiplex reflections of the light, by irradiating the surface of a semiconductor substrate, which has its surface polished to a mirror, with a laser beam at an angle of inclination in the depthwise direction thereby to measure the intensity of the light which has passed. CONSTITUTION:A semiconductor or silicone substrate, which has its both sides polished into mirrors, is evaporated at its one side with such a metal 2, e.g., Au as is free from any anodization. The Au film 2 is selectively removed by the photoetching method to form an aperture 3 of 50mumX50mum which is smaller than the diameter of the laser beam used. This surface is anodized to form an oxidized film 4 which is thicker at the center and thinner at the periphery in the minute region 3. Then, the oxidized film 4 is removed with hydrofluoric acid to form a preset slope 5 in the minute region 3. The silicone substrate thus prepared is exposed to the laser beam in the range of infrared range, and the intensity of the light transmitted is measured to meter the impurity concentration such as the oxygen in the semiconductor. |
