An InP/Si heterojunction photodiode fabricated by self-aligned corrugated epitaxial lateral overgrowth

Abstract

An n-InP/p-Si heterojunction photodiode fabricated by corrugated epitaxial lateral overgrowth (CELOG) method is presented. N-InP/p-Si heterojunction has been achieved from a suitable pattern containing circular shaped openings in a triangular lattice on the InP seed layer on p-Si substrate and subsequent CELOG of completely coalesced n-InP. To avoid current path through the seed layer in the final photodiode, semi-insulating InP:Fe was grown with adequate thickness prior to n-InP growth in a low pressure hydride vapor phase epitaxy reactor. The n-InP/p-Si heterointerface was analyzed by scanning electron microscopy and Raman spectroscopy. Room temperature cross-sectional photoluminescence (PL) mapping illustrates the defect reduction effect in InP grown on Si by CELOG method. The InP PL intensity measured above the InP/Si heterojunction is comparable to that of InP grown on a native planar substrate indicating low interface defect density of CELOG InP despite of 8% lattice mismatch with Si. The processed n-InP/p-Si heterojunction photodiodes show diode characteristics from the current-voltage (I-V) measurements with a dark current density of 0.324 mA/cm2 at a reverse voltage of −1 V. Under the illumination of AM1.5 conditions, the InP/Si heterojunction photodiode exhibited photovoltaic effect with an open circuit voltage of 180 mV, a short circuit current density of 1.89 mA/cm2, an external quantum efficiency of 4.3%, and an internal quantum efficiency of 6.4%. This demonstration of epitaxially grown InP/Si heterojunction photodiode will open the door for low cost and high efficiency solar cells and photonic integration of III-Vs on silicon.

Binary Multifunctional Ultrabroadband Self‐Powered g‐C3N4/Si Heterojunction High‐Performance Photodetector

“…A measurable photovoltaic effect is also observed for the illuminations from 1250 nm (≈11 µW cm −2 ) to 1650 nm (≈6 µW cm −2 ) displayed in the inset of Figure d. As per our knowledge, the observed V OC values over a wide spectral range, from UV to NIR, are among the best reported for silicon‐based self‐powered hybrid photodetectors …”

“…As per our knowledge, the observed V OC values over a wide spectral range, from UV to NIR, are among the best reported for silicon-based self-powered hybrid photodetectors. [31][32][33] illumination at zero bias. This is among the best values reported so far for heterojunction hybrid photodetectors.…”

Antiphase Boundary Free InP Microridges on (001) Silicon by Selective Area Heteroepitaxy

“…High series resistance and severe optical absorption by metal contacts remain challenges for such devices. To date, pioneering research on SAE with microscale patterned III–V buffers has been carried out on either miscut Si (001) substrates or on III–V/Si templates to avoid the generation of APBs. − Generally, APBs nucleate at the edge of single-layer (SL) steps present at (001) Si surfaces . Yet, these approaches pose additional challenges for the compatibility with Si complementary metal-oxide-semiconductor (CMOS) foundries.…”

Optical and interface properties of direct InP/Si heterojunction formed by corrugated epitaxial lateral overgrowth

“…HVPE is an ideal method for III-V based solar cell fabrication since it uses cheap precursors [11], yields high growth rate and gives the growth selectivity necessary for CELOG [12]. Recently an n-InP/p-Si heterojunction photodiode was realized by the CELOG method in a HVPE reactor [13].…”