Atomic Layer Deposition of PbI₂ Thin Films

Research output: Contribution to journalArticleScientificpeer-review

Abstract

Atomic layer deposition (ALD) enables the deposition of numerous materials in thin film form, yet there are no ALD processes for metal iodides. Herein, we demonstrate an ALD process for PbI2, a metal iodide with a two-dimensional (2D) structure that has applications in areas such as photo-detection and photovoltaics. This process uses lead silylamide Pb(btsa)(2) and SnI4 as precursors and works at temperatures below 90 degrees C, on a variety of starting surfaces and substrates such as polymers, metals, metal sulfides, and oxides. The starting surface defines the crystalline texture and morphology of the PbI2 films. Rough substrates yield porous PbI2 films with randomly oriented 2D layers, whereas smooth substrates yield dense films with 2D layers parallel to the substrate surface. Exposure to light increases conductivity of the ALD PbI2 films which enables their use in photodetectors. The films can be converted into a CH3NH3PbI3 halide perovskite, an important solar cell absorber material. For various applications, ALD offers advantages such as ability to uniformly coat large areas and simple means to control film thickness. We anticipate that the chemistry exploited in the PbI2 ALD process is also applicable for ALD of other metal halides.

Original languageEnglish
JournalChemistry of Materials
Volume31
Issue number3
Pages (from-to)1101–1109
Number of pages9
ISSN0897-4756
DOIs
Publication statusPublished - 12 Feb 2019
MoE publication typeA1 Journal article-refereed

Fields of Science

  • AL2O3
  • ENERGY
  • LEAD IODIDE
  • OPTICAL-CONSTANTS
  • PEROVSKITE SOLAR-CELLS
  • 114 Physical sciences
  • 116 Chemical sciences

Cite this

@article{04eda20de1b44845bba1f3c2b10e7794,
title = "Atomic Layer Deposition of PbI₂ Thin Films",
abstract = "Atomic layer deposition (ALD) enables the deposition of numerous materials in thin film form, yet there are no ALD processes for metal iodides. Herein, we demonstrate an ALD process for PbI2, a metal iodide with a two-dimensional (2D) structure that has applications in areas such as photo-detection and photovoltaics. This process uses lead silylamide Pb(btsa)(2) and SnI4 as precursors and works at temperatures below 90 degrees C, on a variety of starting surfaces and substrates such as polymers, metals, metal sulfides, and oxides. The starting surface defines the crystalline texture and morphology of the PbI2 films. Rough substrates yield porous PbI2 films with randomly oriented 2D layers, whereas smooth substrates yield dense films with 2D layers parallel to the substrate surface. Exposure to light increases conductivity of the ALD PbI2 films which enables their use in photodetectors. The films can be converted into a CH3NH3PbI3 halide perovskite, an important solar cell absorber material. For various applications, ALD offers advantages such as ability to uniformly coat large areas and simple means to control film thickness. We anticipate that the chemistry exploited in the PbI2 ALD process is also applicable for ALD of other metal halides.",
keywords = "AL2O3, ENERGY, LEAD IODIDE, OPTICAL-CONSTANTS, PEROVSKITE SOLAR-CELLS, 114 Physical sciences, 116 Chemical sciences",
author = "Georgi Popov and Mattinen, {Miika Juhana} and Timo Hatanp{\"a}{\"a} and Marko Vehkam{\"a}ki and Marianna Kemell and Kenichiro Mizohata and Jyrki R{\"a}is{\"a}nen and Mikko Ritala and Markku Leskel{\"a}",
year = "2019",
month = "2",
day = "12",
doi = "10.1021/acs.chemmater.8b04969",
language = "English",
volume = "31",
pages = "1101–1109",
journal = "Chemistry of Materials",
issn = "0897-4756",
publisher = "American Chemical Society Journals",
number = "3",

}

TY - JOUR

T1 - Atomic Layer Deposition of PbI₂ Thin Films

AU - Popov, Georgi

AU - Mattinen, Miika Juhana

AU - Hatanpää, Timo

AU - Vehkamäki, Marko

AU - Kemell, Marianna

AU - Mizohata, Kenichiro

AU - Räisänen, Jyrki

AU - Ritala, Mikko

AU - Leskelä, Markku

PY - 2019/2/12

Y1 - 2019/2/12

N2 - Atomic layer deposition (ALD) enables the deposition of numerous materials in thin film form, yet there are no ALD processes for metal iodides. Herein, we demonstrate an ALD process for PbI2, a metal iodide with a two-dimensional (2D) structure that has applications in areas such as photo-detection and photovoltaics. This process uses lead silylamide Pb(btsa)(2) and SnI4 as precursors and works at temperatures below 90 degrees C, on a variety of starting surfaces and substrates such as polymers, metals, metal sulfides, and oxides. The starting surface defines the crystalline texture and morphology of the PbI2 films. Rough substrates yield porous PbI2 films with randomly oriented 2D layers, whereas smooth substrates yield dense films with 2D layers parallel to the substrate surface. Exposure to light increases conductivity of the ALD PbI2 films which enables their use in photodetectors. The films can be converted into a CH3NH3PbI3 halide perovskite, an important solar cell absorber material. For various applications, ALD offers advantages such as ability to uniformly coat large areas and simple means to control film thickness. We anticipate that the chemistry exploited in the PbI2 ALD process is also applicable for ALD of other metal halides.

AB - Atomic layer deposition (ALD) enables the deposition of numerous materials in thin film form, yet there are no ALD processes for metal iodides. Herein, we demonstrate an ALD process for PbI2, a metal iodide with a two-dimensional (2D) structure that has applications in areas such as photo-detection and photovoltaics. This process uses lead silylamide Pb(btsa)(2) and SnI4 as precursors and works at temperatures below 90 degrees C, on a variety of starting surfaces and substrates such as polymers, metals, metal sulfides, and oxides. The starting surface defines the crystalline texture and morphology of the PbI2 films. Rough substrates yield porous PbI2 films with randomly oriented 2D layers, whereas smooth substrates yield dense films with 2D layers parallel to the substrate surface. Exposure to light increases conductivity of the ALD PbI2 films which enables their use in photodetectors. The films can be converted into a CH3NH3PbI3 halide perovskite, an important solar cell absorber material. For various applications, ALD offers advantages such as ability to uniformly coat large areas and simple means to control film thickness. We anticipate that the chemistry exploited in the PbI2 ALD process is also applicable for ALD of other metal halides.

KW - AL2O3

KW - ENERGY

KW - LEAD IODIDE

KW - OPTICAL-CONSTANTS

KW - PEROVSKITE SOLAR-CELLS

KW - 114 Physical sciences

KW - 116 Chemical sciences

U2 - 10.1021/acs.chemmater.8b04969

DO - 10.1021/acs.chemmater.8b04969

M3 - Article

VL - 31

SP - 1101

EP - 1109

JO - Chemistry of Materials

JF - Chemistry of Materials

SN - 0897-4756

IS - 3

ER -