Microstructural analysis of N-polar InGaN directly grown on a ScAlMgO₄(0001) substrate

Influence of the substrate misorientation on the properties of N-polar InGaN/GaN and AlGaN/GaN heterostructures

Smooth N-polar InGaN/GaN and AlGaN/GaN multiquantum wells MQWs and heterostructures were grown by metal organic chemical vapor deposition on 0001 sapphire substrates with misorientation angles of 2° –5° toward the a-sapphire plane. For all investigated structures the tendency toward formation of multiatomic steps at the film surface and at interfaces increased with increasing misorientation ang...

Spectroscopic investigation of coupling among asymmetric InGaN/GaN multiple quantum wells grown on non-polar a-plane GaN substrates

Towards InAs/InGaAs/GaAs Quantum Dot Solar Cells Directly Grown on Si Substrate

This paper reports on an initial assessment of the direct growth of In(Ga)As/GaAs quantum dots (QDs) solar cells on nanostructured surface Si substrate by molecular beam epitaxy (MBE). The effect of inserting 40 InAs/InGaAs/GaAs QDs layers in the intrinsic region of the heterojunction pin-GaAs/n⁺-Si was evaluated using photocurrent spectroscopy in comparison with pin-GaAs/n⁺-Si and pin-GaAs/GaA...

GRADED InGaN BUFFERS FOR STRAIN RELAXATION IN GaN/InGaN EPILAYERS GROWN ON SAPPHIRE

Graded InGaN buffers were employed to relax the strain arising from the lattice and thermal mismatch in GaN/InGaN epilayers grown on sapphire. An enhanced strain relaxation was observed in GaN grown on a stack of five InGaN layers, each 200 nm thick with the In content increased in each layer, and with an intermediate thin GaN layer, 10 nm thick inserted between the InGaN layers, as compared to...

On the polar derivative of a polynomial

For a polynomial p(z) of degree n, having all zeros in |z|< k, k< 1, Dewan et al [K. K. Dewan, N. Singh and A. Mir, Extension of some polynomial inequalities to the polar derivative, J. Math. Anal. Appl. 352 (2009) 807-815] obtained inequality between the polar derivative of p(z) and maximum modulus of p(z). In this paper we improve and extend the above inequality. Our result generalizes certai...