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This content will become publicly available on December 27, 2023

Title: High conductivity β-Ga 2 O 3 formed by hot Si ion implantation

This work demonstrates the advantage of carrying out silicon ion (Si+) implantation at high temperatures for forming controlled heavily doped regions in gallium oxide. Room temperature (RT, 25 °C) and high temperature (HT, 600 °C) Si implants were carried out into MBE grown (010) β-Ga2O3films to form ∼350 nm deep Si-doped layers with average concentrations up to ∼1.2 × 1020cm−3. For such high concentrations, the RT sample was too resistive for measurement, but the HT samples had 82.1% Si dopant activation efficiency with a high sheet electron concentration of 3.3 × 1015 cm−2and an excellent mobility of 92.8 cm2/V·s at room temperature. X-ray diffraction measurements indicate that HT implantation prevents the formation of other Ga2O3phases and results in reduced structural defects and lattice damage. These results are highly encouraging for achieving ultra-low resistance heavily doped Ga2O3layers using ion implantation.

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Publication Date:
Journal Name:
Applied Physics Letters
Page Range or eLocation-ID:
Article No. 262101
American Institute of Physics
Sponsoring Org:
National Science Foundation
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