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 μm thick, p-type silicon planar detector, with a bulk resistivity of 3.7 kΩ cm. Charge collection measurements are performed for temperatures between −20 °C to 20 °C. The collected charge decreases by about 8% when the temperature is lowered from 20 °C to −20 °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.