Influence of temperature on measurements of the Two Photon Absorption - Transient Current Technique in silicon planar detectors using a 1550 nm femtosecond fibre laser

The effect of temperature on the excess charge carrier generation and collection, injected using two photon absorption at a wavelength of 1550 nm, is investigated in a 285 & mu;m thick, p-type silicon planar detector, with a bulk resistivity of 3.7 k & omega; cm. Charge collection measurements are performed for temperatures between -20 degrees C to 20 degrees C. The collected charge decreases by about 8% when the temperature is lowered from 20 degrees C to -20 degrees C, which is linked to a decreasing excess charge carrier generation. Further, a decreasing time over threshold is observed for decreasing temperatures, which is associated to an increasing charge carrier mobility.