Fabrication and characterization of heterojunction diodes with HVPE-Grown GaN on 4H-SiC
2001 (English)In: IEEE Transactions on Electron Devices, ISSN 0018-9383, Vol. 48, no 3, 444-449 p.Article in journal (Refereed) Published
GaN/SiC heterojunctions can improve the performance considerably for BJTs and FETs. In this work, heterojunction diodes have been manufactured and characterized. The fabricated diodes have a GaN n-type cathode region on top of a JH-SIC p-type epi layer. The GaN layer was grown with HVPE directly on off-axis SiC without a buffer layer. Mesa structures were formed and a Ti metallization was used as cathode contact to GaN, and the anode contact was deposited on the backside using sputtered Al. Both current-voltage (I-V) and capacitance-voltage (C-V) measurements were performed on the diode structures. The ideality factor of the measured diodes was 1.1 and was constant with temperature. A built in potential of 2.06 V was extracted from I-V-measurements and agrees well with the built in potential from C-V-measurements. The conduction band offset was extracted to 1.1 eV and the heterojunction was of type II. The turn on voltage for the diodes is about 1 V lower than expected and a suggested mechanism for this effect is discussed.
Place, publisher, year, edition, pages
2001. Vol. 48, no 3, 444-449 p.
gallium nitride, HVPE, semiconductor heterojunctions, silicon carbide, contact
IdentifiersURN: urn:nbn:se:kth:diva-20410ISI: 000167253000009OAI: oai:DiVA.org:kth-20410DiVA: diva2:339105
QC 201005252010-08-102010-08-10Bibliographically approved