| AVS 62nd International Symposium & Exhibition | |
| Plasma Science and Technology | Wednesday Sessions |
| Session PS+TF-WeA |
| Session: | Plasma Deposition and Plasma Assisted ALD |
| Presenter: | William Sproul, Reactive Sputtering, Inc |
| Authors: | F. Papa, Gencoa USA V. Bellido-Gonzalez, Gencoa Ltd, UK H. Li, Gencoa Ltd, UK HD. Ngo, University of Applied Sciences Berlin, Germany K. Kröhnert, Fraunhofer Institut IZM Berlin, Germany O. Ehrmann, TU Berlin, Germany K.D. Lang, TU Berlin, Germany P. Mackowiak, Piotr, TU Berlin, Germany W.D. Sproul, Reactive Sputtering, Inc |
| Correspondent: | Click to Email |
Atomic Layer Deposition (ALD) has been slowly gaining acceptance in the field of thin film deposition. Although firstly described in the 1960’s as molecular layering by researchers in the former USSR, the introduction of the technology to the world came via Tuomo Suntola’s group in 1974 (1). The application to ZnS highly ordered films was a real success, and made the electroluminescent displays a reality. Since then the concept has been applied into other technology areas. There are many benefits of ALD, however, in terms of deposition rates, film stress and management of reactive gas species in complex 3D structures there is still a long road ahead.
In order to lower the film stress plasma technology has been applied. Plasma Enhanced ALD (PEALD) has been introduced in order to lower the temperature requirements for the ALD process and also in order to control the properties of the ALD deposited film. The industrialization of such process presents a number of challenges. In PEALD, it is of interest to control the nature and degree of interaction of such plasmas with the surface chemistry. Plasma sources which can control the energy of the ion beam are of special interest. Also, from the industrialisation point of view the sources would need to be able to upscale the process. For those reasons, the authors believe that a Linear Ion Sources (LIS) could help move ALD processes into mass production. LIS’s have been slowly pushing their way through into vacuum coating technology market for over 15 years. Only last year a small circular ion source, which can replicate the functional properties of large LIS’s was introduced (2). This development has enabled rapid transitions from prototyping to manufacturing. The use of such a source is interesting for PEALD as the processes developed in the lab could be easily implemented at an industrial level. As part of the investigation the authors have used the ion source PEALD process on etched silicon wafers in order to produce low temperature conformal depositions. The wafers were etched with different features, like deep aspect ratio trenches, which are of great interest in today’s semiconductor devices. Results will be presented.
1.- Riikka L. Puurunen, “A Short History of Atomic Layer Deposition: Tuomo Suntola’s Atomic Layer Epitaxy” http://onlinelibrary.wiley.com/doi/10.1002/cvde.201402012/pdf
2.- F. Papa, D. Monaghan, V. Bellido-Gonzalez, R. Brown, A. Azzopardi, I. Sorzabal-Bellido, “New Circular Ion Sources for Fast Process Development”, Proceedings to the 2014 Society of Vacuum Coaters Conference, Chicago, USA, 505/856-7188, pages 187-191.