Dry etching and metallization schemes in a GaN/SiC heterojunction device process
2000 (English)In: Materials Science Forum, ISSN 0255-5476, Vol. 338-342, 1049-1052 p.Article in journal (Refereed) Published
Dry etching and metallization schemes are described for a GaN/SiC heterojunction. GaN was reactive ion etched in a chlorine based chemistry (Cl2/Ar), and an ICP etch was used on 4H-SiC using a fluorine based chemistry (SF6/Ar/O2). The etch rates obtained on GaN was above 400 nm/min. High sample temperature from self heating and large dc-bias was the probable cause for the high etch rate. The ICP etch rate on SiC approached 320 nm/min, and the etch selectivity to GaN was >100. The metallization was based on Ti for both n-GaN and p-SiC. TLM and Kelvin structures were used to extract the specific contact resistivity, ÏC. After a 950 Â°C anneal in N2 ÏC on the GaN samples were below 1Â·10-6 Î©cm2 for sputtered contacts in room temperature, and an order of magnitude higher with evaporation. On p-SiC no ohmic behavior was found with a doping of 4Â·1018 cm-3, but the same contact metallization on highly doped areas (>1020 cm-3) showed ohmic behavior with ÏC below 10-4 Î©cm2.
Place, publisher, year, edition, pages
Trans Tech Publications Inc., 2000. Vol. 338-342, 1049-1052 p.
Chlorine, Dry etching, Electric contacts, Fluorine, Metallizing, Nitrides, Plasma etching, Reactive ion etching, Semiconducting gallium compounds, Semiconducting silicon compounds, Silicon carbide, Sputter deposition, Etch selectivity, Gallium nitride, Heterojunctions
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-85421OAI: oai:DiVA.org:kth-85421DiVA: diva2:499839
Sponsors: NASA Glenn Research Center; Air Force Research Laboratory; Office Naval Research; Director of Defence Research and Engineering NR 201408052012-02-132012-02-132012-02-13Bibliographically approved