TY - JOUR
T1 - Atomic Layer Deposition of PbS Thin Films at Low Temperatures
AU - Popov, Georgi
AU - Bačić, Goran
AU - Mattinen, Miika
AU - Manner, Toni
AU - Lindström, Hannu
AU - Seppänen, Heli
AU - Suihkonen, Sami
AU - Vehkamäki, Marko
AU - Kemell, Marianna
AU - Jalkanen, Pasi
AU - Mizohata, Kenichiro
AU - Räisänen, Jyrki
AU - Leskelä, Markku
AU - Koivula, Hanna Maarit
AU - Barry, Seán T.
AU - Ritala, Mikko
N1 - Funding Information:
We thank the Finnish Center of Excellence in Atomic Layer Deposition (ALDCoE 2012-2017) and additional support from the Academy of Finland (Decision Number 309552). We are grateful to the electron microscopy unit of the Institute of Biotechnology at the University of Helsinki for providing TEM instrument access. A part of the research was performed at the OtaNano - Micrometerova Nanofabrication Centre of Aalto University. G.P. acknowledges the doctoral program in Materials Research and Nanosciences (MATRENA) of the University of Helsinki as well as Emil Aaltonen foundation for funding and support. G.B. and S.T.B. acknowledge the QEII-OGSST program for funding and Carleton University for support. H.S. acknowledges the support from the Walter Ahlström Foundation.
Publisher Copyright:
© 2020 American Chemical Society.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/10/13
Y1 - 2020/10/13
N2 - Atomic layer deposition (ALD) is a viable method for depositing functional, passivating, and encapsulating layers on top of halide perovskites. Studies in that area have only focused on metal oxides, despite a great number of materials that can be made with ALD. This work demonstrates that, in addition to oxides, other ALD processes can be compatible with the perovskites. We describe two new ALD processes for lead sulfide. These processes operate at low deposition temperatures (45-155 °C) that have been inaccessible to previous ALD PbS processes. Our processes rely on volatile and reactive lead precursors Pb(dbda) (dbda = rac-N2,N3-di-tert-butylbutane-2,3-diamide) and Pb(btsa)2 (btsa = bis(trimethylsilyl)amide) as well as H2S. These precursors produce high quality PbS thin films that are uniform, crystalline, and pure. The films exhibit p-type conductivity and good mobilities of 10-70 cm² V-1 s-1. Low deposition temperatures enable direct ALD of PbS onto a halide perovskite CH3NH3PbI3 (MAPI) without its decomposition. The stability of MAPI in ambient air is greatly improved by capping with ALD PbS. More generally, these new processes offer valuable alternatives for PbS-based devices, and we hope that this study will inspire more studies on ALD of non-oxides on halide perovskites.
AB - Atomic layer deposition (ALD) is a viable method for depositing functional, passivating, and encapsulating layers on top of halide perovskites. Studies in that area have only focused on metal oxides, despite a great number of materials that can be made with ALD. This work demonstrates that, in addition to oxides, other ALD processes can be compatible with the perovskites. We describe two new ALD processes for lead sulfide. These processes operate at low deposition temperatures (45-155 °C) that have been inaccessible to previous ALD PbS processes. Our processes rely on volatile and reactive lead precursors Pb(dbda) (dbda = rac-N2,N3-di-tert-butylbutane-2,3-diamide) and Pb(btsa)2 (btsa = bis(trimethylsilyl)amide) as well as H2S. These precursors produce high quality PbS thin films that are uniform, crystalline, and pure. The films exhibit p-type conductivity and good mobilities of 10-70 cm² V-1 s-1. Low deposition temperatures enable direct ALD of PbS onto a halide perovskite CH3NH3PbI3 (MAPI) without its decomposition. The stability of MAPI in ambient air is greatly improved by capping with ALD PbS. More generally, these new processes offer valuable alternatives for PbS-based devices, and we hope that this study will inspire more studies on ALD of non-oxides on halide perovskites.
UR - http://www.scopus.com/inward/record.url?scp=85092065896&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.0c01887
DO - 10.1021/acs.chemmater.0c01887
M3 - Article
AN - SCOPUS:85092065896
VL - 32
SP - 8216−8228
JO - Chemistry of Materials
JF - Chemistry of Materials
SN - 0897-4756
IS - 19
ER -