Papers by Keyword: Double Heterostructure

Abstract: To fabricate low threshold semiconductor lasers on silicon, strained quantum well structure is introduced to the well layer. The crystalline, optical, and laser characteristics of GaInAsP separate confinement heterostructure with multiple quantum wells (SCH-MQW) are investigated under various percentages of strain applied to the active layer. It is found that the strain-based III-V heterostructures possessed good crystalline and optical properties to study the current-light characteristics of the lasers. One of the successful achievements is that we do the laser growth only after fabricating InP thin film bonded to silicon substrate using hydrophilic bonding mechanism. GaInAsP SCH-MQW laser structures were fabricated on the directly bonded InP/Si substrate using metal-organic vapor phase epitaxy (MOVPE). Through our integration process and the intentional introduction of strain into the active layer, a significant reduction in threshold current was successfully achieved on the InP/Si substrate. Furthermore, a comparative analysis of the strain distribution within the quantum well structures between the InP and InP/Si substrates was conducted to better understand its impact on device performance.

Abstract: In this paper, charge control mechanism and carrier features have been precisely investigated in InxGa1-xN/InN/InxGa1-xN based quantum-well double heterostructure high electron mobility transistors (QW-DHEMTs). A study of charge control in the InxGa1-xN/InN/InxGa1-xN structure is performed by self-consistently solving Schrödinger equation in conjunction with Poisson’s equation taking into account the spontaneous and piezoelectric polarization effects. The potential profile and the distribution of electron density in the channel as a function of gate voltage are investigated here. A large conduction band offset of about 2.2eV is obtained for the proposed device for In content x=0.05, which ensure better carrier confinement and higher sheet charge density. The influence of In composition(x) and doping concentration of InxGa1-xN upper barrier on sheet charge density and carrier distributions in channel is also presented. This analysis provides a platform to investigate the InN based QW-DHEMTs and to optimized their design.