Delta-Doping of Epitaxial GaN Layers on Large Diameter Si(111) Substrates

Abstract

We report on silicon n-type delta (δ)-doping of gallium nitride (GaN) epitaxial layers grown by metalorganic chemical vapor deposition (MOCVD) on silicon (111) substrates. In a series of group III–nitride epitaxial structures a ∼1-µm-thick Si bulk-doped GaN layer is replaced by 100, 50, 10, 5, or 1 Si δ-doped planes. While Si bulk-doping of GaN aggrandizes the in-plane tensile stress and the wafer bow with respect to undoped structures, δ-doping is found to reduce both stress and wafer bow. Two-dimensional carrier sheet densities between 1012 and 1013 cm-2 per δ-doped plane and electron mobilities of 1429 cm2 V-1 s-1 are achieved.

Gallium nitride surface protection during RTA annealing with a GaOxNycap-layer

“…Gallium nitride (GaN), with its 3.42 eV, direct band gap and its high critical electric field (3.3×10 6 V.cm −1 ) seems to be a well-suited material [1]. Moreover, progress in heteroepitaxial growth has allowed thick GaN layers grown on Si (111) substrates, with well-controlled doping, paving the way for cheaper processing of power devices compared to SiC or diamond [2,3].…”

On the Effect of Step-Doped Quantum Barriers in InGaN/GaN Light Emitting Diodes

“…The strain induced spatial separation of electron-hole wave functions can further be completely eliminated in the non-polar quantum wells and increased radiative recombination rates can thus be obtained [27], [28]. It has also been shown that the material quality and the device performance can be substantially improved by introducing Si doping in quantum barriers [29]- [31]. However, Si-doped barriers or even Si-delta-doped barriers usually have a setback from holes blocking [32], [33], which leads to a high local hole accumulation.…”

Accumulation of Background Impurities in Hydride Vapor Phase Epitaxy Grown GaN Layers

“…On the other hand, in the multilayer structure Si spikes look like Si-delta doping of GaN layer that is known to terminate dislocation propagation. [21][22][23][24] Indeed, we observed that growth interruptions promote narrowing of the X-ray rocking curve full width at half maximum (FWHM), especially when its applied after the growth of first several microns.…”