| 摘要 |
PURPOSE:To regulate a resistance value to be high or low by covering a polycrystalline layer with a plurality of electrodes, and applying a potential difference between the electrodes to alter the resistivity of the layer. CONSTITUTION:Electrodes 7, 8 similarly cover between an electrode 5 (X terminal) and an electrode 6 (Y terminal) covering a polycrystalline silicon layer 3 to form polycrystalline silicon resistors 3a, 3b, 3c. 3 series resistors are formed between the electrodes 5 and 6 on the layer 3, and the resistance values are R1, R2, R3. A voltage of predetermined level is applied between the electrodes 7 and 8, the resistance value of the resistor 3b between the electrodes 7 and 8 is reduced by approx. one/hundredth or more, and the whole resistance value can be reduced to RXY R1+R3. Thus, the resistance value can be regulated to high or low value. |
