| 摘要 |
PURPOSE:To remove the filth stuck to the surface by electric heating, by diffusing the impurity on upper and lower faces of the silicon thin plate to form an electric resistance layer across both faces and by forming an insulating film on this layer and by providing electrodes in end parts. CONSTITUTION:The impurity such as boron is diffused on both faces of silicon plate 5 to form resistance layers 6 and 6' across both faces, and insulating films 7 and 7' of silicon dioxide and so on are formed on these layers by heating in the atmospheric oxygen, and ohmic electrodes 8 and 8' for resistance layers 6 and 6' are provided. This silicon plate is fitted to fitting base 10 having an aperture in the center. As a result, when a pulse current is flowed through lead wires 9 and 9' and electrodes 8 and 8', resistance layer 6 and 6' are heted to a high temperature to remove the filth stuck to the surface. Consequently the window interposed in the path of infrared rays does not interfere with measurement, and thus, infrared rays are measured accurately. |
