Direct band gap electroluminescence from bulk germanium at room temperature using an asymmetric fin type metal/germanium/metal structure

Dong Wang, Takayuki Maekura, Sho Kamezawa, Keisuke Yamamoto, Hiroshi Nakashima

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

We demonstrated direct band gap (DBG) electroluminescence (EL) at room temperature from n-type bulk germanium (Ge) using a fin type asymmetric lateral metal/Ge/metal structure with TiN/Ge and HfGe/Ge contacts, which was fabricated using a low temperature (<400 °C) process. Small electron and hole barrier heights were obtained for TiN/Ge and HfGe/Ge contacts, respectively. DBG EL spectrum peaked at 1.55 μm was clearly observed even at a small current density of 2.2 μA/μm. Superlinear increase in EL intensity was also observed with increasing current density, due to superlinear increase in population of elections in direct conduction band. The efficiency of hole injection was also clarified.

Original languageEnglish
Article number071102
JournalApplied Physics Letters
Volume106
Issue number7
DOIs
Publication statusPublished - Feb 16 2015

Fingerprint

fins
electroluminescence
germanium
room temperature
metals
current density
conduction bands
injection
electrons

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)

Cite this

@article{5b4a6b17f1224cde9af3b3f4439ed35d,
title = "Direct band gap electroluminescence from bulk germanium at room temperature using an asymmetric fin type metal/germanium/metal structure",
abstract = "We demonstrated direct band gap (DBG) electroluminescence (EL) at room temperature from n-type bulk germanium (Ge) using a fin type asymmetric lateral metal/Ge/metal structure with TiN/Ge and HfGe/Ge contacts, which was fabricated using a low temperature (<400 °C) process. Small electron and hole barrier heights were obtained for TiN/Ge and HfGe/Ge contacts, respectively. DBG EL spectrum peaked at 1.55 μm was clearly observed even at a small current density of 2.2 μA/μm. Superlinear increase in EL intensity was also observed with increasing current density, due to superlinear increase in population of elections in direct conduction band. The efficiency of hole injection was also clarified.",
author = "Dong Wang and Takayuki Maekura and Sho Kamezawa and Keisuke Yamamoto and Hiroshi Nakashima",
year = "2015",
month = "2",
day = "16",
doi = "10.1063/1.4913261",
language = "English",
volume = "106",
journal = "Applied Physics Letters",
issn = "0003-6951",
publisher = "American Institute of Physics Publising LLC",
number = "7",

}

TY - JOUR

T1 - Direct band gap electroluminescence from bulk germanium at room temperature using an asymmetric fin type metal/germanium/metal structure

AU - Wang, Dong

AU - Maekura, Takayuki

AU - Kamezawa, Sho

AU - Yamamoto, Keisuke

AU - Nakashima, Hiroshi

PY - 2015/2/16

Y1 - 2015/2/16

N2 - We demonstrated direct band gap (DBG) electroluminescence (EL) at room temperature from n-type bulk germanium (Ge) using a fin type asymmetric lateral metal/Ge/metal structure with TiN/Ge and HfGe/Ge contacts, which was fabricated using a low temperature (<400 °C) process. Small electron and hole barrier heights were obtained for TiN/Ge and HfGe/Ge contacts, respectively. DBG EL spectrum peaked at 1.55 μm was clearly observed even at a small current density of 2.2 μA/μm. Superlinear increase in EL intensity was also observed with increasing current density, due to superlinear increase in population of elections in direct conduction band. The efficiency of hole injection was also clarified.

AB - We demonstrated direct band gap (DBG) electroluminescence (EL) at room temperature from n-type bulk germanium (Ge) using a fin type asymmetric lateral metal/Ge/metal structure with TiN/Ge and HfGe/Ge contacts, which was fabricated using a low temperature (<400 °C) process. Small electron and hole barrier heights were obtained for TiN/Ge and HfGe/Ge contacts, respectively. DBG EL spectrum peaked at 1.55 μm was clearly observed even at a small current density of 2.2 μA/μm. Superlinear increase in EL intensity was also observed with increasing current density, due to superlinear increase in population of elections in direct conduction band. The efficiency of hole injection was also clarified.

UR - http://www.scopus.com/inward/record.url?scp=84923273726&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84923273726&partnerID=8YFLogxK

U2 - 10.1063/1.4913261

DO - 10.1063/1.4913261

M3 - Article

AN - SCOPUS:84923273726

VL - 106

JO - Applied Physics Letters

JF - Applied Physics Letters

SN - 0003-6951

IS - 7

M1 - 071102

ER -