Set Programming Method and Performance Improvement of Phase Change Random Access Memory Arrays

• 作 者: 范茜 陈后鹏 王倩 王月青 吕士龙 刘燕 宋志棠 冯高明 刘波
• 机 构: State Key Laboratory of Functional Materials for Informatics,Shanghai Institute of Micro-system and
• 出 处: Chinese Physics Letters
• 发表日期: 2015年06期
• 关键词: waveform amorphous incomplete residue programmed crystalline stair rectangular c

A novel slow-down set waveform is proposed to improve the set performance and a 1kb phase change random access memory chip fabricated with a 130 nm CMOS technology is implemented to investigate the set performance by different set programming strategies based on this new set pulse.The amplitude difference(I_1-I_2) of the set pulse is proved to be a crucial parameter for set programming.We observe and analyze the cell characteristics with different I_1-I_2 by means of thermal simulations and high-resolution transmission electron microscopy,which reveal that an incomplete set programming will occur when the proposed slow-down pulse is set with an improperly high I_1-I_2.This will lead to an amorphous residue in the active region.We also discuss the programming method to avoid the set performance degradations.

A novel slow-down set waveform is proposed to improve the set performance and a 1kb phase change random access memory chip fabricated with a 130 nm CMOS technology is implemented to investigate the set performance by different set programming strategies based on this new set pulse. amplitude difference (I_1 -I_2) of the set pulse is proved to be a crucial parameter for set programming. We observe and analyze the cell characteristics with different I_1-I_2 by means of thermal simulations and high-resolution transmission electron microscopy, which reveal that an incomplete set programming will occur when the proposed slow-down pulse is set with an improperly high I_1-I_2.This will lead to an amorphous residue in the active region .We also discuss the programming method to avoid the set performance degradations.