GaAs periodic half octagonal cut based nano texturized hexagonal shaped nanopillar array structure for highly responsivephotodetector’s performance

Smriti Baruah,Joyatri Bora,Santanu Maity

doi:10.1007/s11082-021-02951-7

Abstract

Efficient light absorption is the most crucial factor for high spectral responsive photodetection phenomenon. Nanopillars for photodetection constitute a great opportunity in enhancing the light absorption efficiency along with reducing the electrical cross-section of the device. Here an analytical investigation of a proposed periodic GaAs material based half octagonal cut based vertically oriented hexagonal nanopillar array deployed over a 5um x 5um front detector’s surface has been done for attaining an optimum light absorbance by reducing the surface reflectivity of the incoming photons. The geometrical analysis of the proposed model exhibits a 0.999 absorbance and 0.97A/W photoresponsivity along with 86% EQE at 1um operating wavelength.

Highlights

There is a rapid growing advancement in a large number of technological platforms for which photodetectors are very crucial element [1, 2]
In order to boost up this absorption efficiency several approaches have been adopted in terms of III-V nanostructures as they arouse as a promising candidate in minimizing this lattice mismatch owing to their small that could make the lattice mismatch to relax horizontally near the base [7, 8]
This section comprises of the graphical investigation of the effect of varying structural parameters of the proposed nanopillar array model over the photodetector’s performance metrics

Summary

Introduction

There is a rapid growing advancement in a large number of technological platforms for which photodetectors are very crucial element [1, 2]. The reduced reflectivities resulting towards higher absorbing volume for maximum carrier absorption and collection in comparison to their single counterpart [14, 15] In this respect several approaches have been done with III-V based nanopillar to boost the photodetector performance parameters by minimizing the surface reflectivity. In [20] InGaAs based hexagonal shaped nanopillar has been adopted for light reflectance minimization that provides the internal multiple reflection phenomenon to take place within six nanopillar interfaces instead of four This enhances the total amount of overall photon absorption In this paper the authors have proposed a model consisting of periodic half octagonal cut based texturization over the hexagonal shaped nanopillar array so as to reduce the light reflectance phenomenon to a minimal level.

Optical modelling of the NP array structure:

Results and Discussion

Conclusion