A kind of phase-change memory unit and preparation method thereof

Abstract

The invention provides a phase change storage unit which comprises a substrate, a lower electrode metal layer, a first insulating layer, a heating material layer, a second insulating layer, a lower phase change material layer, an upper phase change material layer and an upper electrode metal layer. The phase change storage unit further comprises a blocking layer, the blocking layer is arranged between the lower phase change material layer and the upper phase material layer, and the blocking layer is made of Nb2O5. According to the phase change storage unit, the blocking layer is arranged between the two layers of the phase change materials. The property and the thickness of materials of the blocking layer are controlled to reduce operation current and especially reduce an operation current in polycrystal-orientation amorphous conversion. Thus, 1D1R high-density integration is achieved, and power consumption of a device is reduced. In addition, the invention further provides a preparing method of the phase change storage unit.

Description

【Technical field】 [0001] The invention relates to the technical field of semiconductors, in particular to a phase-change memory unit. 【Background technique】 [0002] Phase change memory technology is based on the phase change proposed by Ovshinsky in the late 1960s (Phys. Rev. Lett., 21, 1450-1453, 1968) and the early 1970s (Appl. Phys. Lett., 18, 254-257, 1971). The idea that thin films can be applied to phase-change storage media is established, and it is a storage device with low price and stable performance. Phase-change memory can be made on silicon wafer substrates, and its key materials are recordable phase-change films, heating electrode materials, heat-insulating materials, and lead-out electrodes. How to reduce device power consumption, etc. The basic principle of phase change memory is to use the change of resistance difference produced by the reversible phase transition of chalcogenide materials to represent two states, so as to realize data storage. [0003] ...

AI Technical Summary

Problems solved by technology

However, this method does not reduce the heat conduction to adjacent units. Although the temperature rise caused will not cause the state of the recording material to change immediately, its resistance will still change significantly, and the data bit information will still remain after multiple operations. There is a possibility of failure, which can seriously affect the service life of the memory

In addition, when doping is used to increase the crystallization temperature, the melting temperature of the thin film phase change material will generally increase accordingly, which in turn will lead to an increase in the power consumption of the phase change memory.

Images