摘要 |
<p>A method of producing a highly reliable mask ROM and the product produced by the method are disclosed. The method is characterized by comprising the steps of forming low doped source-drains to relax the electric field between the gate electrode and drain, thereby suppressing the creation of hot carriers, and of depositing dielectrics of a predetermined thickness between neighbouring gates to control the projection range of impurities implanted into the source-drain region of the bit into which data is to be written, the thickness of the dielectrics being determined such that the projection range does not exceed the junction depth of the source-drain in order to preclude the formation of parasitically doped layers which cause punch-through across an unwritten transistor. <IMAGE></p> |