Flash memory with less susceptibility to charge gain and charge loss

摘要

An integrated circuit is designed to reduce charge gain and charge loss in a flash memory or flash programmable read-only memory. Charge gain and loss caused by moisture or hydrogen diffusion or alternately small contact-to-floating gate distance is reduced by a capping layer disposed over a gate stack and a base layer of the flash memory. The capping layer includes a buffer layer, a first insulative layer, and a second insulative layer. The etch characteristics of at least the first and second insulative layer differs from an interlevel dielectric to control the dimensions of a contact extending through the interlevel dielectric and the capping layer to the base layer.