Open AccessOrigin of acceptor diffusion into silicon substrate during GaN growth by metal organic chemical vapor deposition
Author(s) -
Koji Matsumoto,
Toshiaki Ono,
Yoshio Honda,
Kazuhisa Torigoe,
Maki Kushimoto,
Hiroshi Amano
Publication year - 2019
Publication title -
japanese journal of applied physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.487
H-Index - 129
eISSN - 1347-4065
pISSN - 0021-4922
DOI - 10.7567/1347-4065/ab2657
Subject(s) - gallium , silicon , substrate (aquarium) , materials science , aluminium , chemical vapor deposition , layer (electronics) , diffusion , impurity , acceptor , gallium nitride , chemical engineering , inorganic chemistry , optoelectronics , chemistry , metallurgy , nanotechnology , organic chemistry , oceanography , physics , condensed matter physics , engineering , thermodynamics , geology
This study investigated the change in carrier concentration near the surface of a silicon substrate during gallium nitride (GaN) growth with an aluminum nitride (AlN) buffer layer. It was observed that aluminum, gallium, and carbon diffused into the silicon substrate during the growth process and that the carrier concentration increased with increasing concentration of aluminum and gallium impurities. The gallium that diffused into the silicon substrate was identified as having originated from the gallium that decomposed on the reactor wall during the growth process and the gallium introduced onto the silicon substrate during GaN growth. In contrast, the amount of aluminum that diffused into the substrate was influenced by the duration of the trimethylaluminum (TMAl) flow: a long duration of the TMAl flow step before AlN growth led to a high aluminum concentration near the substrate surface.