Forming a photoluminescent layer on another surface in the dark through lasering of N-type silicon in an electrolyte

Heng Chun Tai, Chao Ching Chiang, Benjamin Tien Hsi Lee

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

Photoetching of n-type silicon induces a photoluminescent (PL) layer containing nanocrystals on the irradiated surface, usually through band gap absorption (wavelength <1100 nm). Here, we demonstrate the formation of a PL layer restricted to the backside surface, not the irradiated surface, by using a 1064 nm Nd:YAG laser. A nanoscale structure of the PL layer is achieved by merely modifying the electrolyte concentration without adding oxidants. To illustrate the working principle, we submit the hypothesis of a quasi-pn structure based on the theory of a quasi-Fermi level. Because of the "injection current"effect due to the quasi-pn structure, the hole current promoted by free-carrier absorption flows toward the backside surface, leading to anodization. This result is remarkable because anodization of n-type silicon is very hard to achieve with just an etchant in the dark.

Original languageEnglish
Pages (from-to)26497-26503
Number of pages7
JournalACS Omega
Volume5
Issue number41
DOIs
StatePublished - 20 Oct 2020

Fingerprint

Dive into the research topics of 'Forming a photoluminescent layer on another surface in the dark through lasering of N-type silicon in an electrolyte'. Together they form a unique fingerprint.

Cite this