1S1R-type phase change storage unit structure and preparation method thereof

Abstract

The present invention discloses a 1S1R-type phase change storage unit structure and a preparation method thereof. The 1S1R-type phase change storage unit structure comprises a top electrode layer, anOTS layer, an intermediate electrode layer, an insulation layer, a bottom electrode layer and a substrate which are stacked in order. The middle portion of a contact surface of the intermediate electrode layer and the insulation layer is recessed to the internal portion of the intermediate electrode, and a phase change material layer is arranged at the recessing position; the position, corresponding to the phase change material layer, of the insulation layer is provided with a heating electrode penetrating the insulation layer, one end of the heating electrode is connected with the phase change material layer, and the other end of the heating electrode is connected with the bottom electrode layer. The coated intermediate electrode layer is employed, and the diameter and the height of the phase change material layer are regulated according to the shape of mushroom-type unit heat distribution to allow the heat to be more uniformly distributed. The contact area of the phase change material layer and the intermediate electrode layer is increased so as to reduce the current density of the phase change materials of the contact area of the phase change material layer and the intermediateelectrode layer, avoid the local programming of the area due to abruptly changed heat, improve the resistance value distribution, reduce the misoperation possibility and improve the reliability of thephase change storage unit.

Description

technical field [0001] The invention relates to a nanoscale phase-change memory unit structure, in particular to a 1S1R type phase-change memory unit structure. [0002] The invention also relates to a preparation method of a nanoscale phase-change memory unit structure, in particular to a preparation method of a 1S1R type phase-change memory unit structure. Background technique [0003] Phase change materials were used in optical discs in the early days, and later became a research hotspot of PCRAM (phase change random access memory) even today. In the field of electrical storage, since Flash, the current mainstream non-volatile memory, will encounter its own physical bottleneck at about 20nm node, seeking the next generation of non-volatile memory has become the main line of development in the storage field. According to the research of Marissa A. Caldwell et al., when the three-dimensional size of the phase change material is 2nm-5nm, it can still exhibit phase change ch...

AI Technical Summary

Problems solved by technology

The heat generated in the above problems will cause more inactive regions of the phase change material to melt, that is, expand the area of ​​the "mushroom-shaped" active region, affect the cell resistance distribution, and thus reduce the reliability of the cell

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