The radiation effects and annealing characteristics of two types of domestic NPN bipolar junction transistors, fabricated with different orientations, were investigated under different dose-rate irradiation. The exper...The radiation effects and annealing characteristics of two types of domestic NPN bipolar junction transistors, fabricated with different orientations, were investigated under different dose-rate irradiation. The experimental results show that both types of the NPN transistors exhibit remarkable Enhanced Low-Dose-Rate Sensitivity （ELDRS）. After irradiation at high or low dose rate, the excess base current of NPN transistors obviously increased, and the current gain would degrade rapidly. Moreover, the decrease of collector current was also observed. The NPN transistor with （111} orientation was more sensitive to ionizing radiation than that with （100} orientation. The underlying mechanisms of various experimental phenomena are discussed in detail in this paper.展开更多
The enhanced low-dose-rate sensitivity （ELDRS） and dose-rate dependence of vertical NPN transistors are investigated in this article. The results show that the vertical NPN transistors exhibit more degradation at lo...The enhanced low-dose-rate sensitivity （ELDRS） and dose-rate dependence of vertical NPN transistors are investigated in this article. The results show that the vertical NPN transistors exhibit more degradation at low dose rate, and that this degradation is attributed to the increase on base current. The oxide trapped positive charge near the SiO2-Si interface and interface traps at the interface can contribute to the increase on base current and the two-stage hydrogen mechanism associated with space charge effect can well explain the experimental results.展开更多
The radiation effects on several properties （reference voltage, digital output logic voltage, and supply current） of dual 8-bit analog-to-digital （A/D） converters （AD9058） under various biased conditions are inv...The radiation effects on several properties （reference voltage, digital output logic voltage, and supply current） of dual 8-bit analog-to-digital （A/D） converters （AD9058） under various biased conditions are investigated in this paper. Gamma ray and 10-MeV proton irradiation are selected for a detailed evaluation and comparison. Based on the measurement results induced by the gamma ray with various dose rates, the devices exhibit enhanced low dose rate sensitivity （ELDRS） under zero and working bias conditions. Meanwhile, it is obvious that the ELDRS is more severe under the working bias condition than under the zero bias condition. The degradation of AD9058 does not display obvious ELDRS during 10-MeV proton irradiation with the selected flux.展开更多
The mechanisms occurring when the switched temperature technique is applied,as an accelerated enhanced low dose rate sensitivity(ELDRS)test technique,are investigated in terms of a specially designed gate-controlled l...The mechanisms occurring when the switched temperature technique is applied,as an accelerated enhanced low dose rate sensitivity(ELDRS)test technique,are investigated in terms of a specially designed gate-controlled lateral PNP transistor(GLPNP)that used to extract the interface traps(Nit)and oxide trapped charges(Not).Electrical characteristics in GLPNP transistors induced by ^(60)Co gamma irradiation are measured in situ as a function of total dose,showing that generation of Nit in the oxide is the primary cause of base current variations for the GLPNP.Based on the analysis of the variations of Nit and Not,with switching the temperature,the properties of accelerated protons release and suppressed protons loss play critical roles in determining the increased Nit formation leading to the base current degradation with dose accumulation.Simultaneously the hydrogen cracking mechanisms responsible for additional protons release are related to the neutralization of Not extending enhanced Nit buildup.In this study the switched temperature irradiation has been employed to conservatively estimate the ELDRS of GLPNP,which provides us with a new insight into the test technique for ELDRS.展开更多
The total-dose response and annealing effect of p-channel metal oxide semiconductor field-effect transistors （PMOSFETs） were investigated at various dose rates and biasing conditions.The results show that the shift ...The total-dose response and annealing effect of p-channel metal oxide semiconductor field-effect transistors （PMOSFETs） were investigated at various dose rates and biasing conditions.The results show that the shift of threshold voltage is more obvious when the dose rate is decreased.Under the various dose rates and biasing conditions,some have exhibited a time-dependent effect and others showed enhanced low-dose-rate sensitivity（ELDRS）.Finally,using the subthreshold-separating method,the threshold-voltage shift is separated into shifts due to interface states and oxidetrapped charges,and the underlying mechanisms of the observed effects are discussed.It has been indicated that the ELDRS effect results from the different quantities of the interface states generated at high and low dose rates.展开更多
This paper describes an approach to prediction of the thick insulators＇ radiation response based on modeling of the charge yield, which is dependent on irradiation temperature, dose rate, and electric field magnitude...This paper describes an approach to prediction of the thick insulators＇ radiation response based on modeling of the charge yield, which is dependent on irradiation temperature, dose rate, and electric field magnitudes. Temperature behavior of the charge yield and degradation saturation due to the interface precursor depletion has been modeled and simulated. Competition between the time-dependent and true dose rate （ELDRS） effects has been simulated and discussed within a framework of the rate-equation-based mathematical model. It was shown that the precursor trap in the thick insulating oxides can be important at high dose rates. It was also shown that full filling of the shallow hole traps in the insulating oxide bulk can cause suppression of dose-rate sensitivity at relatively high dose rates, especially in thick insulators.展开更多
The total ionizing radiation（TID） response of commercial NPN silicon germanium hetero-junction bipolar transistors（Si Ge HBTs） produced domestically are investigated under dose rates of 800 m Gy（Si）/s and 1.3 m...The total ionizing radiation（TID） response of commercial NPN silicon germanium hetero-junction bipolar transistors（Si Ge HBTs） produced domestically are investigated under dose rates of 800 m Gy（Si）/s and 1.3 m Gy（Si）/s with a Co-60 gamma irradiation source. The changes of transistor parameters such as Gummel characteristics, and excess base current before and after irradiation, are examined. The results of the experiments show that for the KT1151, the radiation damage is slightly different under the different dose rates after prolonged annealing, and shows a time dependent effect（TDE）. For the KT9041, however, the degradations of low dose rate irradiation is higher than for the high dose rate, demonstrating that there is a potential enhanced low dose rate sensitivity（ELDRS） effect for the KT9041. The possible underlying physical mechanisms of the different dose rates responses induced by the gamma rays are discussed.展开更多
Radiation induced offstate leakage in the shallow trench isolation regions of SIMC 0.18 μm nMOSFETs is studied as a function of dose rate. A ＂true＂ dose rate effect （TDRE） is observed. Increased damage is observe...Radiation induced offstate leakage in the shallow trench isolation regions of SIMC 0.18 μm nMOSFETs is studied as a function of dose rate. A ＂true＂ dose rate effect （TDRE） is observed. Increased damage is observed at low dose rate （LDR） than at high dose rate （HDR） when annealing is taken into account. A new method of simulating radiation induced degradation in shallow trench isolation （STI） is presented. A comparison of radiation induced offstate leakage current in test nMOSFETs between total dose irradiation experiments and simulation results exhibits excellent agreement. The investigation results imply that the enhancement of the leakage current may be worse for the dose rate encountered in the environment of space.展开更多
A linear voltage regulator was irradiated by ^（60）Coγat high and low dose rates with two bias conditions to investigate the dose rate effect.The devices exhibit enhanced low dose rate sensitivity（ELDRS） under bot...A linear voltage regulator was irradiated by ^（60）Coγat high and low dose rates with two bias conditions to investigate the dose rate effect.The devices exhibit enhanced low dose rate sensitivity（ELDRS） under both biases. Comparing the enhancement factors between zero and working biases,it was found that the ELDRS is more severe under zero bias conditions.This confirms that the ELDRS is related to the low electric field in a bipolar structure. The reasons for the change in the line regulation and the maximum drive current were analyzed by combining the principle of linear voltage regulator with irradiation response of the transistors and error amplifier in the regulator. This may be helpful for designing radiation hardened devices.展开更多
文摘The radiation effects and annealing characteristics of two types of domestic NPN bipolar junction transistors, fabricated with different orientations, were investigated under different dose-rate irradiation. The experimental results show that both types of the NPN transistors exhibit remarkable Enhanced Low-Dose-Rate Sensitivity （ELDRS）. After irradiation at high or low dose rate, the excess base current of NPN transistors obviously increased, and the current gain would degrade rapidly. Moreover, the decrease of collector current was also observed. The NPN transistor with （111} orientation was more sensitive to ionizing radiation than that with （100} orientation. The underlying mechanisms of various experimental phenomena are discussed in detail in this paper.
文摘The enhanced low-dose-rate sensitivity （ELDRS） and dose-rate dependence of vertical NPN transistors are investigated in this article. The results show that the vertical NPN transistors exhibit more degradation at low dose rate, and that this degradation is attributed to the increase on base current. The oxide trapped positive charge near the SiO2-Si interface and interface traps at the interface can contribute to the increase on base current and the two-stage hydrogen mechanism associated with space charge effect can well explain the experimental results.
基金supported by the National Natural Science Foundation of China (Grant No. 11205038)the China Postdoctoral Science Foundation (Grant No. 2012M510951)
文摘The radiation effects on several properties （reference voltage, digital output logic voltage, and supply current） of dual 8-bit analog-to-digital （A/D） converters （AD9058） under various biased conditions are investigated in this paper. Gamma ray and 10-MeV proton irradiation are selected for a detailed evaluation and comparison. Based on the measurement results induced by the gamma ray with various dose rates, the devices exhibit enhanced low dose rate sensitivity （ELDRS） under zero and working bias conditions. Meanwhile, it is obvious that the ELDRS is more severe under the working bias condition than under the zero bias condition. The degradation of AD9058 does not display obvious ELDRS during 10-MeV proton irradiation with the selected flux.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U1532261 and 1630141)
文摘The mechanisms occurring when the switched temperature technique is applied,as an accelerated enhanced low dose rate sensitivity(ELDRS)test technique,are investigated in terms of a specially designed gate-controlled lateral PNP transistor(GLPNP)that used to extract the interface traps(Nit)and oxide trapped charges(Not).Electrical characteristics in GLPNP transistors induced by ^(60)Co gamma irradiation are measured in situ as a function of total dose,showing that generation of Nit in the oxide is the primary cause of base current variations for the GLPNP.Based on the analysis of the variations of Nit and Not,with switching the temperature,the properties of accelerated protons release and suppressed protons loss play critical roles in determining the increased Nit formation leading to the base current degradation with dose accumulation.Simultaneously the hydrogen cracking mechanisms responsible for additional protons release are related to the neutralization of Not extending enhanced Nit buildup.In this study the switched temperature irradiation has been employed to conservatively estimate the ELDRS of GLPNP,which provides us with a new insight into the test technique for ELDRS.
文摘The total-dose response and annealing effect of p-channel metal oxide semiconductor field-effect transistors （PMOSFETs） were investigated at various dose rates and biasing conditions.The results show that the shift of threshold voltage is more obvious when the dose rate is decreased.Under the various dose rates and biasing conditions,some have exhibited a time-dependent effect and others showed enhanced low-dose-rate sensitivity（ELDRS）.Finally,using the subthreshold-separating method,the threshold-voltage shift is separated into shifts due to interface states and oxidetrapped charges,and the underlying mechanisms of the observed effects are discussed.It has been indicated that the ELDRS effect results from the different quantities of the interface states generated at high and low dose rates.
文摘This paper describes an approach to prediction of the thick insulators＇ radiation response based on modeling of the charge yield, which is dependent on irradiation temperature, dose rate, and electric field magnitudes. Temperature behavior of the charge yield and degradation saturation due to the interface precursor depletion has been modeled and simulated. Competition between the time-dependent and true dose rate （ELDRS） effects has been simulated and discussed within a framework of the rate-equation-based mathematical model. It was shown that the precursor trap in the thick insulating oxides can be important at high dose rates. It was also shown that full filling of the shallow hole traps in the insulating oxide bulk can cause suppression of dose-rate sensitivity at relatively high dose rates, especially in thick insulators.
文摘The total ionizing radiation（TID） response of commercial NPN silicon germanium hetero-junction bipolar transistors（Si Ge HBTs） produced domestically are investigated under dose rates of 800 m Gy（Si）/s and 1.3 m Gy（Si）/s with a Co-60 gamma irradiation source. The changes of transistor parameters such as Gummel characteristics, and excess base current before and after irradiation, are examined. The results of the experiments show that for the KT1151, the radiation damage is slightly different under the different dose rates after prolonged annealing, and shows a time dependent effect（TDE）. For the KT9041, however, the degradations of low dose rate irradiation is higher than for the high dose rate, demonstrating that there is a potential enhanced low dose rate sensitivity（ELDRS） effect for the KT9041. The possible underlying physical mechanisms of the different dose rates responses induced by the gamma rays are discussed.
基金Supported by National Science Foundation of China(11305126)
文摘Radiation induced offstate leakage in the shallow trench isolation regions of SIMC 0.18 μm nMOSFETs is studied as a function of dose rate. A ＂true＂ dose rate effect （TDRE） is observed. Increased damage is observed at low dose rate （LDR） than at high dose rate （HDR） when annealing is taken into account. A new method of simulating radiation induced degradation in shallow trench isolation （STI） is presented. A comparison of radiation induced offstate leakage current in test nMOSFETs between total dose irradiation experiments and simulation results exhibits excellent agreement. The investigation results imply that the enhancement of the leakage current may be worse for the dose rate encountered in the environment of space.
文摘A linear voltage regulator was irradiated by ^（60）Coγat high and low dose rates with two bias conditions to investigate the dose rate effect.The devices exhibit enhanced low dose rate sensitivity（ELDRS） under both biases. Comparing the enhancement factors between zero and working biases,it was found that the ELDRS is more severe under zero bias conditions.This confirms that the ELDRS is related to the low electric field in a bipolar structure. The reasons for the change in the line regulation and the maximum drive current were analyzed by combining the principle of linear voltage regulator with irradiation response of the transistors and error amplifier in the regulator. This may be helpful for designing radiation hardened devices.
