Microstructural, chemical bonding, stress development and charge storage characteristics of Ge nanocrystals embedded in hafnium oxide
Source abstract
Abstract
We have grown Ge nanocrystals (NCs) (4.0-9.0 nm in diameter) embedded in high-k HfO2 matrix for applications in floating gate memory devices. X-ray photoelectron spectroscopy has been used to probe the local chemical bonding of Ge NCs. The analysis of Ge-Ge phonon vibration using Raman spectroscopy has shown the formation of compres- sively stressed Ge NCs in HfO2 matrix. Frequency dependent electrical properties of HfO2/Ge-NCs in HfO2/HfO2 sandwich structures have been studied. An anticlockwise hysteresis in the capacitance-voltage characteristics suggests electron injection and trapping in embedded Ge NCs. The role of interface states and deep traps in the devices has been thoroughly exam- ined and has been shown to be negligible on the overall device performance.
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Research context
OpenAlex topics: Semiconductor materials and devices · Advancements in Semiconductor Devices and Circuit Design · Silicon Nanostructures and Photoluminescence
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