Tests of small X-ray Active Matrix Pixel Sensor prototypes at the National Synchrotron Light Source

X-ray Active Matrix Pixel Sensors (XAMPS) were designed and fabricated at Brookhaven National Laboratory. Devices based on J-FET technology were produced on 100 mm high-resistivity silicon, typically 400 μm-thick. The prototypes are square matrices with n rows and n columns with n = 16, 32, 64, 128, 256, 512. Each pixel of the matrix is 90 × 90 μm² and contains a JFET switch to control the charge readout. The XAMPS is a position sensitive ionization detector made on high resistivity silicon. It consists of a pixel array detector with integrated switches. Pixels are isolated from each other by a potential barrier and the device is fully depleted by applying a high voltage bias to the junction on the entrance window of the sensor. The small features of the design presented some technological challenges fully addressed during this production. The first prototypes were tested at the National Synchrotron Light Source (NSLS) with a monochromatic beam of 8 keV and millisecond readout and exhibit good performances at room temperature.