0438857 - FZÚ 2015 RIV DE eng J - Journal Article
Ižák, Tibor - Babchenko, Oleg - Jirásek, Vít - Vanko, G. - Vallo, M. - Vojs, M. - Kromka, Alexander
Selective area deposition of diamond films on AlGaN/GaN heterostructures.
Physica Status Solidi B. Roč. 250, č. 12 (2014), 2574-2580. ISSN 0370-1972. E-ISSN 1521-3951
R&D Projects: GA ČR(CZ) GP14-16549P
Institutional support: RVO:68378271
Keywords : circular high electron mobility transistors * diamond films * GaN substrates * microwave chemical vapor deposition * selective area deposition
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 1.469, year: 2014 ; AIS: 0.483, rok: 2014
DOI: https://doi.org/10.1002/pssb.201451167

Here we present selective area diamond deposition on AlGaN/GaN layers focusing on the elimination of surface and metal contact damage (Ni, NiO, Ir,and IrO2) and suppressing the spontaneous nucleation of diamond. Metal contacts are important for further applications such as diamond-coated GaN based electronic devices. The growth of diamond films was performed by microwave chemical vapor deposition in different gas mixtures with the addition of CO2 or N2 to CH4/H2. Adding CO2 resulted in polycrystalline (PCD), while adding N2 led to the formation of nanocrystalline diamond film (NCD). The diamond deposition was carried out using selective area nucleation in a three-layer sandwich structure (polymer/seeding layer/polymer), which avoided damage to the electrode and GaN surfaces from ultrasonic seeding by diamond particles. No protective layer was used on the GaN surface before diamond deposition, i.e.,diamond films were grown directly on the AlGaN/GaN heterostructures.
Permanent Link: http://hdl.handle.net/11104/0242206