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CN-122028655-A - Self-induced crystallization phase change memory cell and preparation method thereof

CN122028655ACN 122028655 ACN122028655 ACN 122028655ACN-122028655-A

Abstract

The invention relates to a self-induced crystallization phase-change memory cell and a preparation method thereof, wherein the phase-change memory cell comprises a phase-change memory medium layer, and the phase-change memory medium layer is of a multilayer structure formed by alternately growing phase-change material layers and self-induced crystallization In y Te 100‑y material layers In a vertical stacking period, wherein y is more than or equal to 20 and less than or equal to 80. The self-induced crystallization phase change memory unit has the characteristics of quick data writing capability and long service life, can realize high-low resistance difference of more than 3 orders of magnitude, effectively improves the storage stability of multiple resistance states, and can solve the problems of higher power consumption, short service life, low phase change speed and the like of the phase change memory in the prior art.

Inventors

  • WANG RUOBING
  • ZHOU XILIN
  • WEN XIAO
  • SONG ZHITANG
  • SONG SANNIAN

Assignees

  • 中国科学院上海微系统与信息技术研究所

Dates

Publication Date
20260512
Application Date
20250919

Claims (10)

  1. 1. The self-induced crystallization phase-change memory cell comprises a phase-change memory medium layer, and is characterized In that the phase-change memory medium layer is of a multi-layer structure formed by alternately growing phase-change material layers and self-induced crystallization In y Te 100-y material layers In a vertical stacking period, wherein y is more than or equal to 20 and less than or equal to 80.
  2. 2. The self-induced crystalline phase change memory cell of claim 1, wherein the phase change material layer is a chalcogenide material having a reversible structural phase change, comprising one or more of Sb 2 Te 3 、Sb 2 Te、GeTe、Ge 2 Sb 2 Te 5 、Ge 1 Sb 2 Te 4 .
  3. 3. The self-induced crystalline phase change memory cell of claim 1, wherein the phase change material layer has a thickness ranging from 3 nm to 6nm, and the self-induced crystalline In y Te 100-y material layer has a thickness ranging from 3 nm to 6nm.
  4. 4. The self-induced crystalline phase change memory cell of claim 1, wherein the phase change material layer is amorphous or heat treated crystalline, and the self-induced crystalline In y Te 100-y material layer is amorphous or heat treated crystalline.
  5. 5. The self-induced crystalline phase change memory cell of claim 1, wherein the vertical stack period is 2-10 periods.
  6. 6. The self-induced crystalline phase change memory cell of claim 1, wherein the total thickness of the phase change region in the phase change memory medium layer where the phase change occurs is in a range of 12-120 nm.
  7. 7. The preparation method of the self-induced crystallization phase-change memory cell is characterized by comprising the following steps of: s1, providing a substrate with a heating electrode, wherein the heating electrode is coated by an insulating medium; S2, depositing a phase-change storage medium layer on the heating electrode, wherein the phase-change storage medium layer is of a multilayer structure formed by alternately growing a phase-change material layer and a self-induced crystallization In y Te 100-y material layer In a vertical stacking period, and y is more than or equal to 20 and less than or equal to 80; and S3, depositing an upper electrode on the phase-change storage medium layer to obtain the self-induced crystallization phase-change storage unit.
  8. 8. The method according to claim 7, wherein the heating electrode in the step S1 is made of one of Al, W or TiN, and the insulating medium is one of SiO 2 or Si 3 N 4 .
  9. 9. The method of claim 7, wherein the deposition of the phase change memory medium layer in step S2 is performed by physical vapor deposition, chemical vapor deposition or metal organic deposition.
  10. 10. The method of claim 7, wherein the upper electrode in step S3 is made of one of Al, W or TiN.

Description

Self-induced crystallization phase change memory cell and preparation method thereof Technical Field The invention belongs to the technical field of semiconductor devices, and particularly relates to a self-induced crystallization phase change memory cell and a preparation method thereof. Background With the continuous increase of global data and the rapid development of artificial intelligence technology, the demand for data storage is increasingly rising, and the new computer architecture also puts higher demands on the performance of the memory. The phase change memory is one of the most mature novel memory technologies at present, and realizes the storage of data through the rapid nonvolatile phase change of a chalcogenide compound between crystalline state and amorphous state, which is thousands of times faster than Flash in speed and service life and 16 times more than DRAM in capacity. Therefore, the phase change memory is hopeful to fill up the performance difference of Flash and DRAM, reduce the system cost, and is the most potential novel memory technology. In the phase change memory, the selection of the phase change material is particularly important, and the crystallization temperature is taken as an important parameter of the phase change material, so that the phase change material can be directly or indirectly related to key indexes such as the service life, the power consumption, the storage speed and the like of the phase change memory. Taking the currently studied phase change material Sb 2Te3 as an example, the phase change material Sb 2Te3 can spontaneously crystallize in the room temperature environment, so that the amorphous state of the material is very unstable at the room temperature, which is not beneficial to the requirement of the high service life of the phase change memory. Currently, for phase change materials with lower crystallization temperatures, the main solution is generally focused on doping the phase change material to increase its crystallization temperature and thus its data retention. However, the doped phase change material generally has a high melting temperature and is easy to generate phase separation, which brings about the problems of increased power consumption, reduced service life and the like of the phase change memory. Therefore, it is necessary to develop a new phase change memory device in order to balance the phase change speed, power consumption, and data retention of the phase change memory from a new direction. Disclosure of Invention The invention aims to provide a self-induced crystallization phase-change memory unit and a preparation method thereof, which are used for solving the problems of high power consumption, poor thermal stability, short service life, low phase-change speed and the like of a phase-change memory in the prior art. The invention provides a self-induced crystallization phase-change memory unit, which comprises a phase-change memory medium layer, wherein the phase-change memory medium layer is of a multi-layer structure formed by alternately growing a phase-change material layer and a self-induced crystallization In yTe100-y material layer In a vertical stacking period, and y is more than or equal to 20 and less than or equal to 80. Preferably, the material of the phase change material layer is a chalcogenide material with reversible structural phase change, including one or more of Sb2Te3、Sb2Te、GeTe、Ge2Sb2Te5、Ge1Sb2Te4. Preferably, the thickness of the phase change material layer ranges from 3 nm to 6nm, and the thickness of the self-induced crystallization In yTe100-y material layer ranges from 3 nm to 6nm. Preferably, the initial state of the phase change material layer is an amorphous state or a crystalline state after heat treatment, and the initial state of the self-induced crystallization In yTe100-y material layer is an amorphous state or a crystalline state after heat treatment. Preferably, the vertical stacking period is 2-10 periods. Preferably, the total thickness range of the phase change region in the phase change storage medium layer where the phase change occurs is 12-120 nm. Preferably, the self-induced crystalline phase change memory cell is of a confinement type structure or a T-type structure. Preferably, the number of repeatable operations of the self-induced crystalline phase change memory cell is not less than 10 4 times. Preferably, the data writing speed of the self-induced crystallization phase change memory cell is in the nanosecond level. The invention also provides a preparation method of the self-induced crystallization phase-change memory cell, which comprises the following steps: s1, providing a substrate with a heating electrode, wherein the heating electrode is coated by an insulating medium; S2, depositing a phase-change storage medium layer on the heating electrode, wherein the phase-change storage medium layer is of a multilayer structure formed by alternately growing a phase-change material