Contact resistance measurement of Ge₂Sb₂Te₅phase change material to TiN electrode by spacer etched nanowire

Abstract

Ge 2 Sb 2 Te 5 (GST) phase change nanowires have been fabricated using a top-down spacer etch process. This approach enables controls over the dimension and location of the nanowires without affecting the electrical properties. Phase change devices based on these nanowires have been used to systematically investigate the contact resistance between GST phase change material and TiN metal electrodes. The specific contact resistance was found to be 7.96 × 10 −5 Ω cm 2 for crystalline GST and 6.39 × 10 −2 Ω cm 2 for amorphous GST. The results suggest that contact resistance plays a dominant role in the total resistance of GST memory device in both crystalline and amorphous states.

Towards a 3D GeSbTe phase change memory with integrated selector by non-aqueous electrodeposition

“…It has been shown previously that for films thinner than 100 nm both in the crystalline and the amorphous phase the contact resistance dominates. 26,27 The low temperature of the electrodeposition process limits diffusion at the metal-semiconductor interface and hence allows the formation of Schottky barriers with order of magnitude lower reversed bias current than sputtering or evaporation. 28,29 If a correct implementation of PCM memory Schottky barrier can be found this would result in a build-in selector and provide the ability to efficiently scale passive matrices.…”

State dependence and temporal evolution of resistance in projected phase change memory

“…The transfer of current from one material to another is not spread evenly along the contact length, but mainly confined to the transfer length, which is defined by the contact resistivity and sheet resistance. The formation of a Schottky barrier has been reported for example at the interface between amorphous Ge 2 Sb 2 Te 5 and TiN 27 . Based on these resistance values, it is possible to determine the overall resistance of the device (see Supplementary Note 1).…”

Mathematical model and optimization of a thin-film thermoelectric generator

“…Device parameters: s=10 μm, h=4.5 μm, h e =1 μm, h t =0.5 μm. Reference materials from [32] (A), [35] (B) and [36] (C). The points show the simulation results and lines are the results from the mathematical model.…”