PDF Solutions, Inc.
Direct memory characterization using periphery transistors

Abstract:

Disclosed is a system and method for performing direct memory characterization of memory cells in a memory array using peripheral transistors. A memory array is fabricated using a mask layer defining routing for a set of first stage periphery transistors electrically connected to the word lines of the memory array. A revised mask is used for defining a different routing for a set of second stage periphery transistors including different characteristics than the first stage periphery transistors. Testing is conducted by applying a simulated Erase signal to the nonvolatile memory cells and determining which cells are erased. Based on this test, certain characteristics of the first and/or second stage periphery transistors can be identified that provide improved conditions for the nonvolatile memory cells. A product chip can be manufactured using modified versions of the first stage periphery transistors that incorporate the characteristics that provide the improved condition(s).