The University of Connecticut group of Dr. Necmi Biyikli, with others, have recently published a paper (J. Vac. Sci. and Technol. A 37 (2019) 020927) where they were able to achieve good quality, highly stoichiometric AlN using hollow cathode plasma assisted atomic layer deposition (HCPA-ALD) with film densities near bulk values. Because of the high radical flux from the source, significantly lower RF power was required to achieve this improvement in material quality compared to past experience, and shorter plasma on cycles could be used at these lower powers (20 seconds at 100 watts compared to 40 seconds at 300 watts).
Similar improvements in silicon nitride deposition were recently achieved by a team at the University of Texas, Dallas, where excellent quality, highly stoichiometric, high density PA-ALD grown material was achieved using one of our hollow cathode plasma sources (see, for instance, IEEE Electron Device Letters 39 (2018) 1195 ).
Meaglow’s hollow cathode plasma sources are widely used by the ALD Research Community as replacements for inductively coupled plasma (ICP) sources because there is less oxygen contamination when depositing non-oxide materials. However, these recent papers, by the University of Connecticut and the University of Texas, Dallas, illustrate advantages that may be far more important for the industry moving forward. Those being an extremely high radical flux, to the point where the ion signal (ion densities are similar to ICP sources) is swamped by the signal of radicals during optical emission spectroscopy measurements, and relatively low plasma damage (see our company white paper on hollow cathode sources). These result in quicker deposition times with potentially more stoichiometric, better quality material.
The image to right shows the University of Connecticut plasma source with ellipsometer ports and sample entry door. The 4″ diameter source was custom made for use with an Okyay Tech ALD system.
Congratulations to Prof. Dave McIlroy’s group, at the Physics Department of Oklahoma State University, for their recent publication in ACS Sensors Vol. 3 (2018) pg. 2367. The paper, authored by Lyndon Bastatas, provides some of the first results from the Okyay Tech ALD system recently acquired by that group. The ALD system includes a 4″ diameter Meaglow hollow cathode plasma source that was used to pretreat silica nanowire mat samples prior to the thermal deposition of ZnO in the Okyay Tech system. The ALD steps were part of a process to make a collection of 1D structures for ammonium nitrate sensors.
The picture shows Aaron Austin, one of the Oklahoma team next to the Okyay Tech ALD system with Mealgow plasma source shown at the top. Apparently more papers are on the way, with another 2019 publication already available. Meaglow is pleased to be an enabler of this next generation of research, check our products at www.meaglow.com.
Meaglow Ltd. (Privately Held) announces a breakthrough in semiconductor production. As computer chips become smaller and smaller, advanced production techniques, such as Atomic Layer Deposition (ALD) have become more important for depositing thin layers of material. Unfortunately the ALD of some materials has been prone to contamination from the plasma sources used. Meaglow Ltd has developed a hollow cathode plasma source which has reduced oxygen contamination by orders of magnitude, allowing the reproducible deposition of semiconductor materials with improved quality.
THUNDER BAY, ONTARIO.—August 30, 2012—Meaglow Ltd. (Privately Held) announces its low temperature Migration Enhanced Afterglow film growth technique has been used to produce a thick Indium Gallium Nitride (InGaN) layer with strong yellow emission. This recent result bodes well to increase the efficiency and lower production costs of green LEDs and laser diodes. The company is currently seeking collaboration opportunities to enhance the material properties required by industry for lighting, display, medical, and military applications among other uses.