The 4950 Alpha Particle Counter is a gas flow proportional counter, very similar in design to our Model 1950. However, instead of having one active detector/window area of 1000 square centimeters, the Model 4950 has four active window areas. It is essentially two detectors, active on both sides. Each window area is built standard at 900 square centimeters, for a total of 3600 square centimeters. This of course can be changed for custom applications. The standard configuration is designed to hold wafers in a vertical counting configuration . The wafers are attached to special sample trays and placed inside the counter. The Model 4950 is designed to hold up to 8 x 200mm (8") wafers, or up to 12 x 150mm (6") wafers.
Additionally, the Model 4950 can be placed on its side and used in the horizontal configuration for samples that cannot be attached in a vertical position. This would include powder samples, partial wafer samples, pellets, etc. While we cannot use the full 3600 square centimeters, we can use the two windows looking down, and place samples in special trays, allowing for a total of 1800 square centimeters of sample area
Like the Model 1950, the Model 4950 Large Area Low Background Alpha Particle Counter is a gas flow proportional counter designed to allow users to measure and record the alpha flux emitting from samples placed inside the counting chamber(s). Also like the Model 1950 Low Background Counter, the Model 4950 uses the Pro-1950 Alpha Particle Counter Control Software program, which is the software interface between the detector and the host computer. Using the Pro-1950 program, users can define the test parameters such as time and dwell, sample size, region of interest (ROI), detector efficiency, and the like. Additionally, users can use the data analysis portion of the program to determine mean counts, lower limits of detection (LLD), error bar, number of counts, etc. The entire program is Microsoft Windows based and therefore acts very much like all Windows based programs, with point and click commands, pull down menus, etc. The program was designed to be easy to use and easy to understand. To see an image of the Model 4950 Alpha Particle Counter, click here .