A 1060 nm diode laser system for dynamically probing silicon detectors

We have constructed a 1060 nm laser system which has been used to dynamically probe silicon microstrip detectors. A diode laser is coupled to a single mode fiber with a less than 10 μm measured spot size. The laser is driven by a nanosecond pulse with sub-nanosecond rise and fall times. The fast response and small spot size allow for measurements of such quantities as time walk in microstrip detectors. The system has been used to generate 5–100 fC of charge in a 300 μm thick silicon microstrip detector. The laser also has been used in localized depletion voltage measurements and to test the integrity of sensors wire bonded to readout electronics.