High density NOR type read only memory data cell and reference cell network

摘要

Disclosed is a high density NOR type read only memory data cell and reference cell network, in which every single data cell of the data cell network is comprised of a MOSFET the gate of which is connected to a wordline and the source and drain of which are selectively connected through buried N+ to a bitline and a voltage source (ground line or power line) permitting the sources of same group of MOSFETs to be connected together through a buried N+ and the drains of which to be connected together through another buried N+ to form a NOR type of structure so as to eliminate possible contacts and reduce space occupation. The design of reference cell network and the connection of the data cell network eliminate the isolation between different groups of MOSFETs so as to increase the density of data cells and reduce the manufacturing cost. By means of buried N+ bitline connection, the implantation of coding can be made as late as the conventional NAND type to that delivery time can be shortened.