Properties of low temperature PEALD SiO2

Matti Putkonen (Corresponding author), Riikka L. Puurunen, Oili Ylivaara, Markus Bosund, Timo Sajavaara, Mika Vähä-Nissi

Research output: Chapter in Book/Report/Conference proceedingConference abstract in proceedingsScientific

Abstract

ALD has a relatively well-established position as a mainstream coating method in many application areas, mainly due to good film conformality and possibility of nanoscale material modification. Typically ALD deposited oxide materials, such as Al2O3, have surface hydroxyl groups after deposition, contributing to hydrophilic properties. For example measured contact angle for ALD alumina is around 50-60º and as-deposited TiO2 has superhydrophilic properties, which decay soon after deposition to 70-80º. For this presentation, we prepared SiO2 samples by PEALD. According to TOF-ERDA measurements the amount of carbon and nitrogen impurities were relatively low, but hydrogen content increased at low deposition temperatures. Carbon content was below 0.1 at-% if deposition temperature was 200 ºC. Regardless of the deposition temperature hydrogen content remained surprisingly high, being around 10-12 at-%. Low deposition temperature resulted in low refractive indices, most probably due to high hydrogen content. Residual stresses were determined with surface profilometer Veeco Dektak and wafer curvature method using Stoney s equation. The magnitude of the stress of SiO2 was too small to measure accurately for the given samples; most likely it was some tens of MPa on the compressive side. Water contact angles for PEALD SiO2 were below 20º. These values remained practically the same even after few months storage in ambient air. The main contribution for low contact angle is expected to be the high hydrogen impurity content which increases film hydrophilicity.
Original languageEnglish
Title of host publicationTechnical Program & Abstracts
PublisherAmerican Vacuum Society AVS
Publication statusPublished - 2013
Event13th International Conference on Atomic Layer Deposition, ALD 2013 - San Diego, California, San Diego, United States
Duration: 28 Jul 201331 Jul 2013
Conference number: 13

Conference

Conference13th International Conference on Atomic Layer Deposition, ALD 2013
Abbreviated titleALD 2013
CountryUnited States
CitySan Diego
Period28/07/1331/07/13

    Fingerprint

Keywords

  • ALD
  • Atomic Layer Deposition
  • SiO2

Cite this

Putkonen, M., Puurunen, R. L., Ylivaara, O., Bosund, M., Sajavaara, T., & Vähä-Nissi, M. (2013). Properties of low temperature PEALD SiO2. In Technical Program & Abstracts American Vacuum Society AVS.