détecteur au silicium à diffusion

CONT: Silicon Drift Detectors (SDD) are essentially 450 μm-thick discs of high-resistivity silicon which is fully depleted by applying a negative bias voltage to both sides of the disc. On one side of the planar structure the bias is graduated across the device by means of a series of ""drift rings"" such that a strong transverse electric field component is developed within the structure. This is used to direct electrons produced as a result of x-ray interactions towards a small charge collecting anode. On the opposite side of the device (x-ray entrance side) there is a uniform shallow implanted junction contact to allow good low energy x-ray sensitivity and minimum charge loss.