GaAs-based In0.83Ga0.17As photodetector structure grown by gas source molecular beam epitaxy

Optimization of InAlAs buffers for growth of GaAs-based high indium content InGaAs photodetectors

“…1(a) and (b). The cross-hatch pattern is associated with the strain fields of misfit dislocations aligned with the [110] and [1][2][3][4][5][6][7][8][9][10] directions [7], which should be related to the different growth rates around the dislocations. Compared to sample A, the crosshatch patterns of sample B is less pronounced.…”

“…Growth condition was exactly the same as our previous study [5]. Each wafer consisted of a 2.5-μm-thick N þ InAlAs buffer layer and a 1.5-μm-thick n À In 0.83 Ga 0.17 As absorption layer followed by a 530-nm-thick P þ InAlAs cap.…”

“…So far, In x Ga 1 À x As (x4 0.53) PDs are often fabricated on InP substrates, and the cutoff wavelength has been extended up to 2.9 μm by using gas source molecular beam epitaxy (GSMBE) [3]. When In x Ga 1 À x As PDs were transferred to GaAs substrates, the major difficulty would be that the nearly 4% increased lattice mismatch for the same indium content x [4,5]. However, GaAs substrates hold the advantages of higher robustness, lower cost and larger size as compared to InP substrates.…”

Epitaxy and Device Properties of InGaAs Photodetectors with Relatively High Lattice Mismatch

“…However, to maximize these effects, the composition, number, and thickness of the DA should be further optimized. In our recent researches, two In 0.83 Ga 0.17 As PD structures with continuously graded InAlAs MBL were grown on (1 0 0)-oriented S-doped InP or GaAs epi-ready substrates by GSMBE [30]. In this way, the lattice mismatch will increase from +2.1 to +5.9% for In 0.83 Ga 0.17 As on GaAs compared to that on InP.…”

“…The detailed buffer schemes for samples GS1, GS2, GS3, and GS4 were listed in Table 6. Growth condition was exactly the same as that in our previous study [30]. The strategies of substrate temperature graded from 530 to 460°C, and the uniform temperature of 490 °C were adopted for the deposition of continuously graded In x Al 1−x As and fixed-composition In 0.83 Al 0.17 As buffer, respectively.…”