| 摘要 |
Shorting together of adjacent, oppositely doped semiconductive regions (23, 21) at the surface of a substrate caused by misalignment of contact windows (W') over portions of both regions is avoided by providing a first set of contact regions (21') of one (p) conductivity type of sufficient width to easily avoid the misalignment caused problem, and a second set of contact regions (21) of the opposite (n) conductivity type and of the minimum possible width (to obtain maximum device density on the substrate) which, owing to their small width, give rise to the misalignment problem. The doping (p type) of the regions (21') of the first set is made higher than the doping (p type) of the regions (23) adjacent to the regions (21) of the first set. Prior to applying the conductive contact materials through the contact windows, impurities are non selectively implanted through the windows at a concentration sufficient to reverse the conductivity type (p) of any portions of the adjacent regions (23) exposed by the misaligned windows (W'), but of insufficient concentration to reverse the conductivity type (p) of the second set of regions (21'). |
