Spatial atmospheric atomic layer deposition: a new laboratory and industrial tool for low-cost photovoltaics

Abstract

International audienceRecently, a new approach to atomic layer deposition (ALD) has been developed that doesn't require vacuum and is much faster than conventional ALD. This is achieved by separating the precursors in space rather than in time. This approach is most commonly called Spatial ALD (SALD). In our lab we have been using/developing a novel atmospheric SALD system to fabricate active components for new generation solar cells, showing the potential of this novel technique for the fabrication of high quality materials that can be integrated into devices. In this minireview we will introduce the basics of SALD and illustrate its great potential by highlighting recent results in the field of photovoltaics

Research Update: Atmospheric pressure spatial atomic layer deposition of ZnO thin films: Reactors, doping, and devices

“…1(c)). 5,6,16,27,31 The isolation of each gas channel is also maintained by positioning the substrate <100 nm from the gas manifold and ensuring that the exhaust flow of gases balances the inlet gas flow. 31 The substrate position may be maintained by mechanically constraining the gas manifold over the substrate, 25 floating the gas manifold over the substrate (where the gas curtains act as frictionless bearings), 32 or by floating the substrate over the gas manifold.…”

“…30 in device synthesis is highly preferable for their industrial application. 5,14,17,18 Detailed reviews of closed chamber and atmospheric pressure spatial ALD reactors and their development can be found in Refs. 5 and 6.…”

“…We also seek to standardize the terminology used. For example, the various terms previously employed to describe these reactors are atmospheric atomic layer deposition (AALD), [23][24][25][26] spatial atmospheric atomic layer deposition (SAALD), 5,27,28 and atmospheric spatial atomic layer deposition. 29 Here, the term is standardized to AP-SALD.…”

“…4 Atmospheric pressure spatial atomic layer deposition (AP-SALD) is an emerging technique to produce functional oxides, such as ZnO, for devices. 5 AP-SALD has the capability of rapid, atmospheric and in-line processing in industrial environments. [5][6][7] Spatial atomic layer deposition (SALD) evolved from conventional atomic layer deposition (ALD) to overcome the limitations of ALD in a vacuum environment: although ALD can controllably produce conformal, pinhole-free thin films, 5,6,[8][9][10][11][12][13] long purge steps are needed between the alternating precursor exposure steps to prevent their intermixing in the gas phase and to ensure that they are separately chemisorbed onto the substrate ( Fig.…”

Improved Heterojunction Quality in Cu₂O-based Solar Cells Through the Optimization of Atmospheric Pressure Spatial Atomic Layer Deposited <br />Zn_1-xMg_xO

“…In this work we utilize an open-air, scalable thin film deposition process called atmospheric pressure spatial atomic layer deposition (AP-SALD) to grow n-type oxides for Cu 2 O-based solar cells. The advancement of AP-SALD over conventional ALD is that in the former, precursors are separated in space rather than in time 10 . During the deposition process, a substrate oscillates back and forth on a heated platen under a gas manifold which contains precursor gas channels separated by inert gas channels, as shown in Figure 2.…”