Glove Box Systems, Thermal Space Simulation, Transfer Mechanisms and Device Testing Capability

Unique Vacuum Technology Issue
Unique Integrated Glove Box Systems Over the past year Angstrom Engineering has developed a system that combines a thin film vacuum deposition system with the added flexibility of an integrated glove box environment. This system is ideally suited for the customer that requires substantial flexibility when working with materials that are sensitive to atmospheric moisture and/or oxygen. Each system can be custom designed to suit our customer's requirements. There is no longer a need to conform to pre-existing deposition styles and/or source arrangements, which could result in less than ideal product development. A general system configuration consists of a 28" square 304 SSTL chamber that is approximately 20" deep, integrated to a four-port glove box. Two ports enable dual handed source and substrate manipulation within the vacuum chamber for process preparation when the front door of the system is open. The other two ports are used for handling the customer's materials, substrates, or additional tooling in the main portion of the glove box. The chamber itself has two access doors, a front door that slides to the side on rails while accessing the chamber interior through the glove box, and a hinged back door for performing periodic maintenance and cleaning from the laboratory. More information? Select either of the images to the right. ►	Figure 1. Integrated Glove Box - Front View, Chamber Door Closed. Figure 2. Integrated Glove Box - Rear View, Maintenance Door Closed.

New Thermal Space Simulation Systems The vacuum chamber shown in the rendered image to the right is constructed from 304 stainless steel, is 45 inches in diameter and approximately 49.5 inches long. The chamber in sealed by means of a hinged front door using an elastomer o-ring flange system. The chamber has a glass bead blasted finish on the outside and inside surfaces, both for appearance and to reduce surface out-gassing respectively. The chamber is provided with a cradle based four point floor support frame system. Attached to each of the four support feet are swivel casters providing system mobility, in addition to screw jacks enabling height adjustment and leveling of the chamber. The vacuum system is fitted with a temperature controlled shroud assembly to simulate the thermal absorptivity of space. The thermal shroud is constructed from two sections; an Aluminum base/mounting plate connected to a copper shroud dome. The copper shroud is formed to match the shape of the chamber above the Aluminum base plate. Solar absorption end plates are located to either end of the shroud reducing radiant transfer to unwanted areas of the chamber. The Aluminum plate is supplied with a series of tapped holes for mounting/clamping equipment to the plate during testing, improving thermal conductivity to specific components. The inside of the shroud is coated with a high absorptivity, low thermal emittance solar selective paint selected by the customer to account for the emission of test radiation. To enhance process stability the shroud assembly is thermally isolated from the chamber walls. The temperature is controlled on the shroud assembly by passing fluid through a tubing network that has been welded/brazed to the respective sections of the shroud. A conventional fluid circulation system will expose the shroud to a thermal cycle ranging from -60°C to 120°C without the use of liquid nitrogen. However with minimal modification the thermal shroud may be used with a liquid nitrogen circulation system to reach cryogenic temperatures.	Figure 3. Thermal Space Simulation - Rendered Assembly, Front Door Open. Figure 4. Thermal Space Simulation - Rendered Thermal Shroud, Some Surfaces Made Transparent.

System-Link Transfer Mechanism Advantages The System-Link transfer system enables parallel system integration of two or more systems. The transfer system chamber consists of interconnected 6-inch tube weldments and multi-directional crosses. Within the transfer chamber is a full length rail support system and a cable driven dual directional cart assembly. The rail cart assembly is capable of carrying either an Angstrom Engineering substrate holder, a mask support plate, or both together. Rail cart motion is manually driven from either end of the trolley chamber by the use of a rotary vacuum feedthrough and cable pulley assembly. Push-pull device stops are located at each system transfer position reducing user alignment time and improving transfer repeatability. In vacuum precision linear transfer fork supports are provided at each system transfer position improving transfer usability, and enabling large item mobility (i.e. Substrate and mask support plate assemblies.). Top port multi-directional cross viewports in combination with operation mirror assemblies, allows a wide range of individuals to easily monitor transfer actions and steady state positioning. Viewports are also provided at both ends of the transfer system increasing available light and enabling quick determination of rail cart positioning. A precision linear transfer arm is provided for each deposition chamber along the transfer system incorporating manual cable drive assemblies, creating stationary transfer positions at each system location. The parallel system modular configuration allows possible future extensions and system upgrades. The system shown in the images to the right incorporated multiple transfer modules, interconnecting three thin film vacuum deposition chambers and one glow discharge plasma cleaning load-lock chamber. By linking individual system chambers through a vacuum environment you can ensure process isolation, leading to a more thorough understanding of specific process stage characteristics.	Figure 5. System Link Transfer - Interconnected Load Lock with Multiple Vacuum Deposition Chambers. Figure 6. System Link Transfer - Internal Rail Cart Assembly View.

Enhanced Calibration & Device Testing Capability Through ongoing research Angstrom Engineering has recently developed a mathematical method for thin film thermal evaporation tooling factor calibration. Due to fully developed 3D CAD models of every system we are now capable of pre-calibrating film thickness control for any evaporation system in a fraction of the time involved with experimental method. Our mathematical method has proven to be accurate with 1% of the target film thickness after only a single process test. Not only does this eliminate weeks of running samples, measurements and re-calibration, but reduces manufacturing time providing a nearly calibrated system upon installation at a customer's facility. At the request of a customer Angstrom Engineering has the ability to process device testing as depicted in the image to the right. Figure 7 shows an organic light emitting diode (OLED) during testing within an integrated glove box system after initial system calibration. This form of testing has be done in-house before customer acceptance of the system, in addition to onsite customer trials before final shipment. In order for device testing to be accomplished substrates, materials and process recipes must be supplied to Angstrom Engineering prior to system assembly completion. Angstrom Engineering can not guarantee device operation as material quality and process recipes substantially influence results and are the sole responsibility of the customer.	Figure 7. OLED Device Testing - Angstrom Engineering Procedures During Customer System Calibration.

Next Exhibiting Trade Shows Upcoming conferences that Angstrom Engineering will be attending and/or hosting a booth at are shown to the right. ►	AVS Science & Tech. Society Santa Clara Convention Center Santa Clara, California March 1-4, 2004 Table number: 150 Society of Vacuum Coaters Dallas, Texas April 26-27, 2004 Booth number: 810

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