Alumina-rich spinel: A new substrate for the growth of high quality GaN-based light-emitting diodes

Growth and structural properties of thick GaN layers obtained by sublimation sandwich method

“…Gallium nitride is a promising material for blue light emitting devices such as diodes and lasers [1,2]. Doped GaN is also a prospective spintronic material [3][4][5].…”

Comparison of high quality GaN‐based light‐emitting diodes grown on alumina‐rich spinel and sapphire substrates

“…As a result we have successfully replicated on 1:3 spinel-(111) the standard MOCVD growth conditions initially developed at CRHEA for GaN on sapphire-(0001) [6]. The GaN epilayers resulting from simultaneous growth runs are morphologically, optically and electrically as good on 1:3 spinel as on sapphire, as detailed elsewhere [7]. In this article, we report a systematic study on the electroluminescence (EL) properties of light-emitting diodes (LEDs) grown simultaneously on sapphire and 1:3 spinel.…”

“…www.pss-c.com the mosaicity of GaN is still slightly higher than on state-of-the-art sapphire [7]. It is most likely due to better carrier injection into the active region, as discussed below.…”

Growth and annealing properties of Mg0.4Al2.4O4 crystal

“…In order to further improve the quality of GaN epitaxial layers and therefore InGaN LEDs, SAINT-GOBAIN Crystals, a major supplier of substrates, has developed a new material, less mismatched with GaN but still chemically close to sapphire: an alumina-rich cubic spinel, MgAl 6 O 10 [5], also denoted MgO nAl 2 O with n = 3. This crystal has a lower thermal expansion mismatch with GaN: ˛≈ 2.2 × 10 −6 K −1 (measured at 800 • C), together with a lower lattice mismatch of −11.5% [6]. Compared with stoichiometric spinel (MgAl 2 O 4 ), alumina-rich spinel benefits from compositional softening [7] and can easily be sliced and polished into large diameter wafers [5].…”