Abstract
We demonstrated the formation of excellent Ohmic contact to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula> -type GaN (including the plasma etching-damaged <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula> -type GaN which otherwise exhibited undetectable current within ±5 V) by the post-growth diffusion of magnesium. The specific contact resistivity on the order of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10^{-{4}}\,\,\Omega $ </tex-math></inline-formula> .cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> (extracted at V = 0 V) was achieved on the plasma-damaged <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula> -GaN with linear current-voltage characteristics by the transfer length method (TLM) measurement. The improvement in current by a factor of over 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">9</sup> was also obtained on the plasma-damaged <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">p-n</i> junction diode after the same Mg-treatment. These experimental results indicate a great potential of post-growth diffusion of Mg to overcome the bottleneck of forming a good Ohmic contact to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula> -GaN.
Highlights
GaN is a wide-bandgap semiconductor that experiencedIndex Terms—Diffusion processes, Doping, Gallium nitride, Magnesium, Ohmic contacts rapid development in optoelectronics and power electronics since the first demonstration of p-type conduction [1]
A good Ohmic contact to p-GaN has become the bottleneck to improve the performance of related electronic devices such as merged PiN Schottky diode, p-n junction diodes, bipolar transistors and p-channel unipolar
We demonstrated excellent Ohmic contact to p-GaN by post-growth diffusion of Mg at relatively low temperature and short time such as 550 °C and 10 min, even on the plasma-etched p-GaN
Summary
GaN is a wide-bandgap semiconductor that experienced. The common and unavoidable plasma etching process introduce N-vacancy as compensating donor which reduces the hole concentration of the surface p-GaN and makes it act like lightly-doped p-GaN, leading to the increased difficulty of obtaining Ohmic contact to p-GaN [5]–[7]. A good Ohmic contact to p-GaN has become the bottleneck to improve the performance of related electronic devices such as merged PiN Schottky diode, p-n junction diodes, bipolar transistors and p-channel unipolar. This work is resubmitted for review on 11 November 2021.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
