Method for preparing phase-change memory

Abstract

The invention discloses a method for preparing a phase change memory, which comprises the following steps: providing a silicon chip, and depositing a medium layer on the surface of the silicon chip; depositing a bottom electrode layer on the medium layer; preparing SixO with set thickness on the bottom electrode layer as a middle insulating layer; preparing through holes on the insulating layer, and then filling tungsten onto the through holes to communicate a bottom electrode, so as to form a tungsten plug; depositing a TiN electrode layer with set thickness on the insulating layer; preparing a transverse electrode pair with set line width on the TiN electrode layer, and connecting the transverse electrode pair with the formed tungsten plug simultaneously; after the transverse electrode pair is formed, depositing a phase change material with set thickness, and using electron beam exposure and reaction ion etching to form a nanometer line made of the phase change material to be connected with the formed electrode pair to form a basic memory unit; and preparing a top layer electrode. The method combines high density of a longitudinal structural unit and low power consumption of a transverse structural unit, and is favorable for improving integral performance of the phase change memory.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, and relates to a method for preparing a memory, in particular to a method for preparing a phase-change memory. Background technique [0002] Compared with the current dynamic random access memory (DRAM) and flash memory (FLASH), phase change random access memory (PCRAM) has obvious advantages: it is small in size, low in driving voltage, low in power consumption, fast in read and write speed, and non-volatile. Phase change memory is not only a non-volatile memory, but it is also possible to make multi-machine storage, and it is suitable for ultra-low temperature and high temperature environments, and is resistant to radiation and vibration. Therefore, it will not only be widely used in daily portable electronic products, but also in aerospace has huge potential applications. In particular, its high speed and non-volatility just make up for the shortcomings of flash memory (FLASH) and ferr...

AI Technical Summary

Problems solved by technology

What is being studied now is the unit device with vertical structure. This structure can increase the density of the device, but the thermal efficiency in this structure is very low. Only less than 1% of the heat is really used for phase change, and the rest of the heat They are all diffused in the bottom electrode and the dielectric layer, and the heat diffused in the bottom electrode accounts for about 70%.

At the same time, it is difficult to control the size of vertical device units below 100nm due to the limitation of current fabrication technology

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