Temperature-dependent stress in diamond-coated AlGaN/GaN heterostructures

0464052 - FZÚ 2017 RIV GB eng J - Journal Article
Ižák, Tibor - Jirásek, Vít - Vanko, G. - Dzuba, J. - Kromka, Alexander
Temperature-dependent stress in diamond-coated AlGaN/GaN heterostructures.
Materials and Design. Roč. 106, Sep (2016), s. 305-312. ISSN 0264-1275. E-ISSN 1873-4197
R&D Projects: GA ČR(CZ) GP14-16549P
Grant - others:AV ČR(CZ) SAV-16-02
Program: Bilaterální spolupráce
Institutional support: RVO:68378271
Keywords : thermally induced stress * Raman spectroscopy * polycrystalline diamond film * GaN
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 4.364, year: 2016

In this study, we present a methodology for evaluation of thermally induced stress in diamond microstructures. The diamond strips (2 mm in width and 0.78 or 2.8 μm in thickness) were selectively grown on AlGaN/GaN heterostructures. The stress was evaluated from the Raman shift of the diamond peak position within the temperature range from 50 to 400°C. The shift was measured at two positions, i.e. at center and edge of the strip. We observed that for temperature increase from 50 to 400°C the difference between stresses evaluated at the center and edge of diamond strip (stress) decreases from 0.27 to 0.18 GPa and from 0.32 to 0.1 GPa for the thinner and thicker diamond films, respectively. Experimental data were compared with FEM simulations. The simulations fitted well to experimental data and confirmed that the stress difference between the center and edge of diamond strip was caused by thermal stress component.

Permanent Link: http://hdl.handle.net/11104/0263370