| 摘要 |
<p>PURPOSE:To program and make non-effective by the impression of fixed constant current pulses, and to easily revise and change a part or the whole of stored information, by constituting a memory part using elements. CONSTITUTION:A D* is formed of polycrystalline Si films 7 and 8, and a DH is a P-N junction diode formed of the polycrystalline Si film 8 and an N<+> layer 3. When the constant current pulse whereby the diode D* is biased in an inversed direction is impressed on the both ends of the PROM elements and 9, the diode D* is broken down in junction and short-circuited, thus becomes approx. equivalent to a resistor R, then the electric characteristic is greatly changed, and accordingly the PROM elements are programmed. When a constant current pulse larger than one used for program is impressed between the both ends 9 and 3 so that the diode DH is biased in a forward direction, the polycrystalline Si films 7 and 8 are fused, and therefore the PROM elements become non-effective.</p> |
