Speaker
Description
Radiation hardness is a vital property of sensors used in high-energy physics experiments. Significant effort has been made to develop particle detectors for the harsh radiation environments of the Large Hadron Collider (LHC) and the High-Luminosity Large Hadron Collider (HL-LHC). One suitable candidate material, silicon grown with the magnetic Czochralski method, possesses a high intrinsic oxygen concentration enabling it to withstand higher radiation fluences. The aggregation of oxygen atoms leads to the formation of electrically active defects, known as thermal donors, which can be used for bulk compensation, thereby lowering the depletion voltage and adjusting the bulk resistivity. In our work, we study p-type magnetic Czochralski silicon diode sensors with thermal donors. Thermal donor formation was achieved by sintering the silicon at temperatures of 410℃ and 430℃. We evaluated the sensors using a variety of methods, including the current-voltage (IV) and capacitance-voltage (CV) characterization, as well as single-photon absorption (SPA) and two-photon absorption (TPA) transient current techniques (TCT). We analyzed the sensors' electrical behavior and SPA-TCT response to 660 nm red and 1060 nm infrared laser pulses injected into the sensors' top and edge. Additionally, a 1550 nm TPA-TCT setup was used to probe the diode bulk beneath the optical window via top injection. By analyzing the obtained waveforms from the SPA and TPA signals, we characterize the movement of charge carriers in the bulk at different bias voltages. We also touch on the specifics of the amplification and readout chains, comparing signals from current-sensitive and charge-sensitive amplifiers to analyze the transients.