Randy L. Yach

Mechanism of charge induced plasma damage to EPROM cells during fabrication of integrated circuits

Plasma damage mechanisms can be very complex, especially when manufacturing non-volatile memories such as EPROM and flash memories. Plasma damage at via etch can manifest itself as a charge retention failure in the memory cell during product testing. This paper investigates the interaction of UV radiation, classical plasma charging due to non-uniform plasma, and standard integrated circuit fabrication procedures in order to propose an apparent charge loss failure mechanism for non-volatile memories.

Effect of reactive ion etching chemistry on plasma damage in EPROM cells

There has been much work on studying the effects of plasma damage on microelectronic circuits. Most of this work has focused on gate oxide damage as a result of plasma charging. This paper explores damage to nonvolatile memory cells, specifically erasable programmable read only memories (EPROMs). This damage is unique in that it only affects EPROM cells and their ability to store charge. Several causes of damage discussed here include plasma chemistry, which was found to be the key to solving the problem.