FABRICATION OF CCD IMAGE SENSORS USING SINGLE LAYER POLYSILICON

摘要

A method for fabricating CCD imaging structures having single layer polysilicon gates and employing conventional photolithographic techniques and equipment is disclosed. The comprises the steps of providing a silicon substrate; growing a dielectric layer substantially overlying the silicon substrate; depositing a first layer of polysilicon substantially overlaying the dielectric layer; creating a plurality of polysilicon gates and inter-gate gaps from the first layer of polysilicon, each of plurality of the polysilicon gates having a predetermined line width, each pair of the plurality of polysilicon gates having a predetermined inter-gate gap; depositing a second layer of polysilicon of a predetermined thickness substantially overlaying the defined plurality of polysilicon gates and the inter-gate gaps, the predetermined thickness of the second layer of polysilicon being about one half of the predetermined inter-gate gap thickness minus a desired inter-gap thickness; removing at least a portion of the second layer of polysilicon so as to define the plurality of polysilicon gates having the desired inter-gap thickness.