Efficient Smart Verify Method For Programming 3D Non-Volatile Memory

摘要

In a programming operation of a 3D stacked non-volatile memory device, an initial set of memory cells on a selected word line layer, involving fewer than all memory cells on a selected word line layer, are programmed first as a test case to determine optimal conditions for programming the remaining memory cells on the selected word line layer. For example, a number of program-verify iterations or loops which are needed to program the initial set of memory cells an initial amount is determined. This loop count is then stored, e.g., within the initial set of memory cells, within the remaining memory cells, within memory cells on a remaining word line layer, or in a data register, and programming of the initial set of memory cells continues to completion. Subsequently, the loop count is retrieved and used to determine an optimal starting program voltage for programming the remaining memory cells.

主权项

1. A method for programming, comprising:
programming an initial number of memory cells using a respective starting program voltage, each memory cell of the initial number of memory cells is arranged in a respective initial set of memory cells, each respective initial set of memory cells comprises an active area and is formed above a substrate in multiple physical levels of memory cells in a three-dimensional non-volatile memory, each active area comprises a pillar which extends vertically in the three-dimensional non-volatile memory; determining a count of program loops used in the programming of the initial number of memory cells; and programming a remaining number of memory cells using a respective starting program voltage which is determined based on the count, each memory cell of the remaining number of memory cells is in a respective remaining set of memory cells, the initial number of memory cells and the remaining number of memory cells are arranged along respective memory holes at a common word line in the three-dimensional non-volatile memory.