A Comparative Study on the Effects of Passivation Methods on the Carrier Lifetime of RIE and MACE Silicon Micropillars

Amal Kabalan

doi:10.3390/app9091804

Abstract

Silicon micropillars have been suggested as one of the techniques for improving the efficiency of devices. Fabrication of micropillars has been done in several ways—Metal Assisted Chemical Etching (MACE) and Reactive Ion Etching (RIE) being the most popular techniques. These techniques include etching through the surface which results in surface damage that affects the carrier lifetime. This paper presents a study that compares the carrier lifetime of micropillars fabricated using RIE and MACE methods. It also looks at increasing carrier lifetime by surface treatment using three main approaches: surface passivation by depositing Al2O3, surface passivation by depositing SiO2/SiN, and surface passivation by etching using KOH and Hydrofluoric Nitric Acetic (HNA) solution. It was concluded that passivating with SiO2 and SiN results in the highest carrier lifetime on the MACE and RIE pillars.

Highlights

Micro and nanoscale structures have improved the performance of many electronic devices such as solar cells [1,2], light emitting diodes [3], detectors [4], and batteries [5]
Theresults resultsare are Semilabtool toolthat thatallows allows carrier carrier lifetime lifetime using using microwaves microwaves to presented in multiple figures that depict the average carrier lifetime of a plane silicon wafer
It should be noted that back surface passivation was not performed

Summary

Introduction

Micro and nanoscale structures have improved the performance of many electronic devices such as solar cells [1,2], light emitting diodes [3], detectors [4], and batteries [5]. The large junction area and surface area on the pillar arrays compared to traditional planar junction silicon solar cells makes it challenging to fabricate high performance devices due to an increase in surface defects. This makes the choice of the micropillar fabrication technique very critical since it has an impact on the quality of the surface of the pillars. Glow-discharge plasma is used to generate the gas-phase etching environment, which consists of positive and negative ions, electrons, radicals, and neutrals from a feed gas (CF4). At the same time chemical reactions between radicals and neutrals

Methods

Results

Conclusion