| 摘要 |
PURPOSE:To contrive to offer rapidly an MROM required by users by a method wherein impurity ions are implanted to the arbitrary region of a semiconductor element from the upper part of the semiconductor element completed with metal wiring, and after then the impurity ions are activated electrically according to microwave heating. CONSTITUTION:Impurity ions are implanted selecting the region 6 of a part of semiconductor elements 7, 8 formed with metal wiring layers, and after then by performing microwave heating, impurity ions thereof are activated to store informations to the semiconductor elements 7, 8. According to microwave heating, because the region implanted with impurity ions can be heated selectively, melting or the loss of the metal wiring is not generated. Because impurity regions can be formed selectively in the specified regions of the semiconductor elements 7, 8 even after completion of the metal wiring process like this, turnaround time of a semiconductor memory unit such as a mask programmable ROM (MROM), etc., can be shortened utilizing the fact thereof. |
