Monolithic integration of perovskites on Ge(001) by atomic layer deposition: a case study with SrHfxTi1-xO3


This work reports the growth of crystalline SrHfxTi1-xO3 (SHTO) films on Ge (001) substrates by atomic layer deposition. Samples were prepared with different Hf content x to explore if strain, from tensile (x = 0) to compressive (x = 1), affected film crystallization temperature and how composition affected properties. Amorphous films grew at 225 °C and crystallized into epitaxial layers at annealing temperatures that varied monotonically with composition from -530 °C (x= 0) to -660 °C (x= 1). Transmission electron microscopy revealed abrupt interfaces. Electrical measurements revealed 0.1 A/cm2 leakage current at 1 MV/cm for x= 0.55.

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This researchwas supportedbytheNationalScience Foundation (Award CMMI-1437050) and the Air Force Office of Scientific Research (Grant FA9550-14-1-0090).

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Correspondence to John G. Ekerdt.

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Current Address: Towerjazz Texas, San Antonio, TX 78251, USA.

Current Address: Intel Corporation, Chandler, AZ 85226, USA.

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Hu, S., McDaniel, M.D., Posadas, A. et al. Monolithic integration of perovskites on Ge(001) by atomic layer deposition: a case study with SrHfxTi1-xO3. MRS Communications 6, 125–132 (2016).

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