Two types of the silicon avalanche photodiode (Si-APD) array detector have been developed for synchrotron X-ray experiments on nuclear resonant scattering. A 16×2 array of 3×5mm2 pixels (thickness: 0.15mm) was designed for large solid angle measurements of the nuclear resonant inelastic scattering on 57Fe (nuclear resonant level: 14.4keV). A 4×2 array of 0.5×1 mm2 pixels (thickness: 0.05mm) was produced for measurements of the nuclear resonant forward scattering. X-ray detectors using the Si-APD arrays were tested on detection efficiency and timing performance for 14.4-keV X-rays. With a proper readout electronics for each pixel, an array of Si-APDs can be an X-ray detector having a count-rate capacity of up to 108 s-1 per pixel, position resolution and a sub-nanosecond time resolution.
