The radiation-sensitive field effect transistors(RADFET)radiation dosimeter is a type of radiation detector based on the total dose effects of the p-channel metal-oxide-semiconductor(PMOS)transistor.The RADFET chip wa...The radiation-sensitive field effect transistors(RADFET)radiation dosimeter is a type of radiation detector based on the total dose effects of the p-channel metal-oxide-semiconductor(PMOS)transistor.The RADFET chip was fabricated in United Microelectronics Center 8-inch process with a six-layer photomask.The chip including two identical PMOS transistors,occupies a size of 610μm×610μm.Each PMOS has a W/L ratio of 300μm/50μm,and a 400 nm thick gate oxide,which is formed by a dry-wet-dry oxygen process.The wet oxygen-formed gate oxide with more traps can capture more holes during irradiation,thus significantly changing the PMOS threshold voltage.Pre-irradiation measurement results from ten test chips show that the initial average voltage of the PMOS is 1.961 V with a dispersion of 5.7%.The irradiation experiment is conducted in a cobalt source facility with a dose rate of 50 rad(Si)/s.During irradiation,a constant current source circuit of 10μA was connected to monitoring the shift in threshold voltage under different total dose.When the total dose is 100 krad(Si),the shift in threshold voltage was approximately 1.37 V,which demonstrates that an excellent radiation function was achieved.展开更多
In this work, we studied on the boron-ions implantation, including the implant dose and post-annealing temperature on the performance of PMOS radiation field-effect transistors(RADFETs) in experimental. The possible t...In this work, we studied on the boron-ions implantation, including the implant dose and post-annealing temperature on the performance of PMOS radiation field-effect transistors(RADFETs) in experimental. The possible traps and defects induced by ions implantation in the gate-oxide and their further impacting on the sensitivity and dose range of RADFETs were analyzed qualitatively. Our devices had the dry/wet/dry sandwich gate-oxide of 420 nm thick. Different ion-implanting doses and post-annealing temperatures were carried out during the RADFETs fabrication. We built a real time auto-measurement system to realize the auto-state-switch between irradiation and read-out modes, and in-situ measurement of output voltage for ten devices in turn at once of radiation experiment. The threshold voltage, dose range and sensitivity of RADFETs were extracted and analyzed in detail. The results showed that the highest sensitivity of 229 mV/Gy achieved when the implant dose was2.2×1011 cm.2 and the post-annealing temperature was 1000°C, and the dose range of 34 Gy as well.展开更多
To monitor the integral dose deposited in the BESⅢ electromagnetic calorimeter whose performance degrades due to exposure to the BEPC Ⅱ background, a 400 nm IMPL RadFET dosimeter-based integral dose online monitor s...To monitor the integral dose deposited in the BESⅢ electromagnetic calorimeter whose performance degrades due to exposure to the BEPC Ⅱ background, a 400 nm IMPL RadFET dosimeter-based integral dose online monitor system is built, After calibration with the ^60Co source and verification with TLD in the pulse radiation fields, an experiment was arranged to measure the BEPC Ⅱ background online. The results are presented.展开更多
文摘The radiation-sensitive field effect transistors(RADFET)radiation dosimeter is a type of radiation detector based on the total dose effects of the p-channel metal-oxide-semiconductor(PMOS)transistor.The RADFET chip was fabricated in United Microelectronics Center 8-inch process with a six-layer photomask.The chip including two identical PMOS transistors,occupies a size of 610μm×610μm.Each PMOS has a W/L ratio of 300μm/50μm,and a 400 nm thick gate oxide,which is formed by a dry-wet-dry oxygen process.The wet oxygen-formed gate oxide with more traps can capture more holes during irradiation,thus significantly changing the PMOS threshold voltage.Pre-irradiation measurement results from ten test chips show that the initial average voltage of the PMOS is 1.961 V with a dispersion of 5.7%.The irradiation experiment is conducted in a cobalt source facility with a dose rate of 50 rad(Si)/s.During irradiation,a constant current source circuit of 10μA was connected to monitoring the shift in threshold voltage under different total dose.When the total dose is 100 krad(Si),the shift in threshold voltage was approximately 1.37 V,which demonstrates that an excellent radiation function was achieved.
基金supported by the National Basic Research Program of China(Grant No.2015CB352100)
文摘In this work, we studied on the boron-ions implantation, including the implant dose and post-annealing temperature on the performance of PMOS radiation field-effect transistors(RADFETs) in experimental. The possible traps and defects induced by ions implantation in the gate-oxide and their further impacting on the sensitivity and dose range of RADFETs were analyzed qualitatively. Our devices had the dry/wet/dry sandwich gate-oxide of 420 nm thick. Different ion-implanting doses and post-annealing temperatures were carried out during the RADFETs fabrication. We built a real time auto-measurement system to realize the auto-state-switch between irradiation and read-out modes, and in-situ measurement of output voltage for ten devices in turn at once of radiation experiment. The threshold voltage, dose range and sensitivity of RADFETs were extracted and analyzed in detail. The results showed that the highest sensitivity of 229 mV/Gy achieved when the implant dose was2.2×1011 cm.2 and the post-annealing temperature was 1000°C, and the dose range of 34 Gy as well.
文摘To monitor the integral dose deposited in the BESⅢ electromagnetic calorimeter whose performance degrades due to exposure to the BEPC Ⅱ background, a 400 nm IMPL RadFET dosimeter-based integral dose online monitor system is built, After calibration with the ^60Co source and verification with TLD in the pulse radiation fields, an experiment was arranged to measure the BEPC Ⅱ background online. The results are presented.
