GEM-D2 Process

GEM-R2D2 Process

ALD-MCP(Microchannel Plate)

Arradiance developed and patented Atomic Layer Deposition(ALD) thin films revolutionizing microchannel plates, channel electron multipliers, photomultiplier tubes and other devices, such as image intensifier (II) tubes used in night vision. These specialized ALD film properties improve the functionality of state-of-the-art devices by significantly improving efficiency, noise, and lifetime performance.

Reported by Albert Lehmann, at panda on September 4, 2013

Shown below is the improvement of Photonis MCPs utilizing GEMStar and Arradiance ALD technology showing almost no Q.E. (Quantum Efficiency) drop at 5.6 C/cm2.

Night vision -Using advanced ALD thin film deposition techniques and state-of–the-art materials characterization Arradiance developed and patented ALD thin films with targeted electrical, mechanical and optical properties optimizing MCP performance. Films developed for MCP application have been optimized for resistance and secondary electron emission in order to replicate and improve upon the behavior of the lead- glass film used by; current state-of-the-art MCP technology; a fiber optic-based technology fundamentally unchanged from the early 1970s. The functionality of the MCP relies upon an elevated temperature hydrogen reduction of the surface film to simultaneously form the electrically active resistive and secondary electron (SE) emissive layers. The lead-based glass system as presently used lacks the capability to independently optimize mechanical, resistive and emissive properties and also suffers from poor glass composition control that results in ion induced damage and lifetime degradation, Arradiance developed resistive and emissive films have demonstrated substrate independence and MCP performance improvements in gain (10x) and lifetime as a direct result of the ability to tailor all elements to maximize MCP performance.

A typical image intensifying tube, used in night vision devices, is shown. In operation, light from the scene being viewed, which can be a low-level visible light and/or infrared light, is focused by the optical input element through the glass plate in the cathode window onto the photocathode. The photocathode converts the light striking it into electrons. The electrons travel into the MCP and are then multiplied. The resulting electrons strike the phosphor screen which converts the electrons into visible light.

A major drawback of the conventional image intensifying devices is that the electrostatic fields established in the II tube that transport the electrons from the photocathode coating to the MCP also transport positive ions present within the MCP back towards the photocathode. Because such positive ions can be of considerable size they are capable of causing physical and chemical damage to the photocathode. In order to counter these effects, state-of-the-art image intensifying devices use a thin ion barrier film on the input side of the MCP to block the ions from impacting or reacting with the photocathode. There are several drawbacks to the use of the ion barrier film:

Nanotechnology and Biomedical – Film requirements broadly cover mechanical, electrical, optical and thermal properties. Arradiance has developed films which have the ability to conformably coat extremely high aspect ratio structures, such as the 300:1 capillary shown to the right, while retaining the ability to tailor film properties to the application. Such high aspect ratio coverage coupled with the demonstrated capability to functionalize thin films is directly applicable to chemical and biological sensor devices as well as micro fluidic, emulsification and semiconducting nanotube / nanowire coatings. Biomedical imaging devices, utilizing FLIM and FRET illumination, can benefit from the improved imaging provided by the advanced MCP devices developed using Arradiance thin film technology.

Scientific and Chemical – Analytical instrumentation used in scientific disciplines makes extensive use of charged particle detection devices for materials characterization. The MCP technology developed by Arradiance will significantly impact the analytic detection market, by improving performance (gain, sensitivity and noise) and device lifetime. Shown at right is the detection improvement resulting from Arradiance developed emissive layer for an astronomical detection device. Significant improvement in the pulse height distribution translates directly to improved detection capability. Chemical catalysis requires the use of substrates which possess ultra high surface area supports for catalytic reactions. Arradiance has demonstrated functionalized films, capable of high aspect ratio coverage which display angstrom level control over catalyst thickness and digital control of film stoichiometry.