Henry Bleichner - Academia.edu (original) (raw)
Papers by Henry Bleichner
Proceedings of the 6th International Symposium on Power Semiconductor Devices and Ics, 1994
This paper discusses the importance of reliable physical models/parameters used in drift-diffusio... more This paper discusses the importance of reliable physical models/parameters used in drift-diffusion device simulation of power devices. Simple devices, diodes, and considerably more complicated structures, Gate Turn-off thyristors (GT0:s) have been investigated. Using both electrical and optical measurement techniques, comparisons have been made between measured data and simulated results. A proposal is made for new Auger recombination parameter values and for the temperature dependence of the Shockley-Read-Hall lifetime in the temperature range of 300-450 K.
52nd Annual Device Research Conference, 1994
Technical Digest., International Electron Devices Meeting, 1988
ABSTRACT
Solid-State Electronics, 1992
The failure mechanisms of Gate-Turn-Off (GTO) thyristors are investigated. Measurements based on ... more The failure mechanisms of Gate-Turn-Off (GTO) thyristors are investigated. Measurements based on a time-resolved free-carrier absorption (FCA) technique are used to support the presented models. The measurements serve to map the local carrier densities two-dimensionally, at any time of the switching cycle. Inductively loaded GTOs under snubberless operation are studied close to the safeoperating area (SOA) limit. Several important features of the destructive process are established. First, the existence of a quasi space-charge region, QSC, in the n base and charge focusing at the anode side of the device is noticed during the fall-time period. Secondly, a piling up of holes in the p base is followed by current filamentation during the tail period. The sequential behaviour of different phenomena and their possible causal explanations are also established. The expansion of the QSC towards the anode emitter causes the enhancement and focusing of the charge distribution in the vicinity of this junction. Two possible failure mechanisms, viz. local dynamic punch-through in the n base and local dynamic avalanche injection in the blocking junction are discussed in the light of the experimental results. It is also suggested that both the above mentioned failure mechanisms can be part of the chain of events leading to device failure. Regardless of which mechanism dominates, a high peak of excess holes appears in the p base in the beginning of the tail period. This charge debiases the cathode junction locally, i.e. compensates the negative bias of the cathode junction, and current filaments connecting the cathode and anode sides of the device are formed. The excessive power dissipation in the dominant filament causes failure and permanent damage.
Solid-State Electronics, 1986
Journal of Applied Physics, 1994
Recent articles have been published claiming that the ambipolar diffusion coefficient of semicond... more Recent articles have been published claiming that the ambipolar diffusion coefficient of semiconductors, D(sub a), is basically independent of the excess-carrier concentration, thus contradicting the conventional result of, for example, Fletcher. However, only a few experimentally verified papers on this subject are published. In the present work, a detailed experimental analysis of the ambipolar diffusion coefficient is presented regarding both
Journal of Applied Physics, 1996
Using three measurement techniques the injection and temperature dependence of the Shockley–Read–... more Using three measurement techniques the injection and temperature dependence of the Shockley–Read–Hall (SRH) carrier lifetime was studied. Flying-spot scanning was used for the measurement of lifetimes under low-level injection. Open-circuit carrier decay for the measurement of high-injection lifetime, and deep-level transient spectroscopy for the characterization of active recombination centers. The samples were silicon p-i-n type diodes (p+-n-n+) irradiated with 15 MeV electrons for lifetime control. The measurements consistently show that two defect levels located at Ec−0.164 eV (E1) correlated to the vacancy-oxygen complex and Ec−0.421 eV (E4) correlated to the single-negatively charged state of the divacancy are significant for the SRH lifetime in different injection domains in the low-doped n-type region. The E1 recombination center is dominating the high-injection lifetime and the E4 center is dominating the low-injection lifetime. Similar to other authors, additional defect levels have also been observed, but the E1 and E4 levels seem sufficient to explain the behavior of electron-irradiated semiconductor power devices.
IEEE Transactions on Instrumentation and Measurement, 1990
The measurement of two-dimensional (2-D) excess-carrier distribution in a gate GTO by a time-reso... more The measurement of two-dimensional (2-D) excess-carrier distribution in a gate GTO by a time-resolved infrared-absorption technique is discussed. The optical scanning system employs a wide memory digital oscilloscope for data acquisition and a computer system for control, data processing, and display. Maps of the carrier distribution in the active GTO device are produced under steady-state conditions as well as during
IEEE Transactions on Instrumentation and Measurement, 1991
IEEE Transactions on Electron Devices, 1994
The free-carrier absorption (FCA) technique is used for mapping of the carrier content in a dual-... more The free-carrier absorption (FCA) technique is used for mapping of the carrier content in a dual-cathode gate turnoff thyristor (GTO) at different stages of the turn-off cycle. The FCA technique outputs 3-D maps based on 2-D measurements of local carrier concentration. The measurements are time resolved, thus making a transient response converted into a corresponding sequence of carrier maps. The dual-cathode device is shown to be sufficient for determining the transient behavior in a multicathode structure. The destruction mechanism and reasons for turn-off failure are investigated. The GTO device is inductively loaded and asymmetrically gate contacted in order to emulate a realistic mode of operation. The gate-driving conditions are altered, and the importance of the turn-off gain for turn-off failure is established. The case of equal ON-state cathode currents in both segments is particularly highlighted. The influence of snubber circuits is also discussed.
IEEE Transactions on Electron Devices, 1995
The influence of the anode shorting on the turn-off failure of GTO thyristors is investigated. Tw... more The influence of the anode shorting on the turn-off failure of GTO thyristors is investigated. Two types of shorting patterns, viz., "fmger"-and "ring"-type anode designs, are compared with a non-shorted design. The inductively loaded GTO unit cells are measured under snubberless operation close to the safe-operating area (SOA) limit. The critical anode blocking voltage was obtained for a constant anode current density by varying the turn-off gain, G. The investigation has shown that the turn-off voltage capability of both types of anode-shorted GTO's is deteriorated for high G values. The "ring"-type anode design, however, shows better voltage blocking capability than the "finger" type. This behavior is attributed to the formation of a cylindrical high drift-current density filament at the end of the storage and beginning of the fall-time periods. The electric field in this region, which is referred to as a quasi space-charge region (QSC), is strongly G dependent. Measurements based on the timeresolved free-carrier absorption (FCA) technique are used to map the carrier-density redistribution inside the unit cell during the turn-off switching cycle. For the first time, 3-D simulations of the GTO cell are also presented in order to support the model of dynamic punch-through failure at high G values, which was proposed in earlier papers.
IEEE Transactions on Electron Devices, 1993
A time-resolved free-carrier absorption technique is used to describe transient gate turn-off thy... more A time-resolved free-carrier absorption technique is used to describe transient gate turn-off thyristor (GTO) phenomena two-dimensionally . The measurements are spatially resolved in the anode-to-cathode direction, as well as in the direction determined by the cathode length. Effects associated with charge removal during the GTO turn-off cycle with respect to external circuit conditions are discussed. The behavior of resistively and inductively loaded GTO:s is explained on basis of experimental results. Modeled results, published by others, are used for comparison. VOBECKY et al: 2-D ANALYSIS OF TURN-OFF PROCESS IN GTO 2353.
IEEE Electron Device Letters, 2000
The MOS-controlled thyristor (MCT) is well suited for very high power applications. The maximum c... more The MOS-controlled thyristor (MCT) is well suited for very high power applications. The maximum capability of turn-off currents for p-channel MCT's was so far limited to low values (<10 A at 1000 V snubberless switching) due to strong sublinear current scaling with respect to the device area. In this letter we investigate this phenomenon by full device scale transient carrier
Membrane Technology, 1993
A well calibrated free-carrier absorption (FCA) technique was used to characterize the physical p... more A well calibrated free-carrier absorption (FCA) technique was used to characterize the physical properties of P-I-N diode samples at different temperatures and injection levels. The measurements were compared with simulations in order to check the validity of some models and parameters which commonly appear in the simulation programs. The samples, as well as measurement temperatures (30-150°C) and injection levels (1015-1017cm¿3),
Materials Science Forum, 2001
Proceedings of the 6th International Symposium on Power Semiconductor Devices and Ics, 1994
This paper discusses the importance of reliable physical models/parameters used in drift-diffusio... more This paper discusses the importance of reliable physical models/parameters used in drift-diffusion device simulation of power devices. Simple devices, diodes, and considerably more complicated structures, Gate Turn-off thyristors (GT0:s) have been investigated. Using both electrical and optical measurement techniques, comparisons have been made between measured data and simulated results. A proposal is made for new Auger recombination parameter values and for the temperature dependence of the Shockley-Read-Hall lifetime in the temperature range of 300-450 K.
52nd Annual Device Research Conference, 1994
Proceedings of 9th International Symposium on Power Semiconductor Devices and IC's, 1997
A tandem accelerator has been used to simulate the effect of cosmic rays on the DC stability prop... more A tandem accelerator has been used to simulate the effect of cosmic rays on the DC stability properties of a reverse biased pn diode. 30 MeV Carbon ions, with a maximum ionization of 130 eV/Å, were stopped in a reverse biased pn-junction. If the electric field is high enough, the large number of electron-hole pairs created by the ions results
Proceedings of the 13th International Symposium on Power Semiconductor Devices & ICs. IPSD '01 (IEEE Cat. No.01CH37216), 2001
4H-SiC diodes with 4.5 kV blocking and epitaxially grown anode emitters show near theoretical for... more 4H-SiC diodes with 4.5 kV blocking and epitaxially grown anode emitters show near theoretical forward voltages of 3.08 V at 100 A/cm 2 and 4.10 V at 1000 A/cm2 at RT (2.96 V and 4.15 V at 125°C), while diodes with implanted emitters show 3.5-3.8 V at 100 A/cm2 with -4 mV/K. The transient recovery losses (Erec, Qrr) are as low as 1/100 of the reference silicon device. Paralleling of the SiC diodes with silicon IGBTs enables 400 A switching, and system loss savings of nearly 50% compared to state-of-art silicon technology
Materials Science Forum, 2002
ABSTRACT
Proceedings of the 6th International Symposium on Power Semiconductor Devices and Ics, 1994
This paper discusses the importance of reliable physical models/parameters used in drift-diffusio... more This paper discusses the importance of reliable physical models/parameters used in drift-diffusion device simulation of power devices. Simple devices, diodes, and considerably more complicated structures, Gate Turn-off thyristors (GT0:s) have been investigated. Using both electrical and optical measurement techniques, comparisons have been made between measured data and simulated results. A proposal is made for new Auger recombination parameter values and for the temperature dependence of the Shockley-Read-Hall lifetime in the temperature range of 300-450 K.
52nd Annual Device Research Conference, 1994
Technical Digest., International Electron Devices Meeting, 1988
ABSTRACT
Solid-State Electronics, 1992
The failure mechanisms of Gate-Turn-Off (GTO) thyristors are investigated. Measurements based on ... more The failure mechanisms of Gate-Turn-Off (GTO) thyristors are investigated. Measurements based on a time-resolved free-carrier absorption (FCA) technique are used to support the presented models. The measurements serve to map the local carrier densities two-dimensionally, at any time of the switching cycle. Inductively loaded GTOs under snubberless operation are studied close to the safeoperating area (SOA) limit. Several important features of the destructive process are established. First, the existence of a quasi space-charge region, QSC, in the n base and charge focusing at the anode side of the device is noticed during the fall-time period. Secondly, a piling up of holes in the p base is followed by current filamentation during the tail period. The sequential behaviour of different phenomena and their possible causal explanations are also established. The expansion of the QSC towards the anode emitter causes the enhancement and focusing of the charge distribution in the vicinity of this junction. Two possible failure mechanisms, viz. local dynamic punch-through in the n base and local dynamic avalanche injection in the blocking junction are discussed in the light of the experimental results. It is also suggested that both the above mentioned failure mechanisms can be part of the chain of events leading to device failure. Regardless of which mechanism dominates, a high peak of excess holes appears in the p base in the beginning of the tail period. This charge debiases the cathode junction locally, i.e. compensates the negative bias of the cathode junction, and current filaments connecting the cathode and anode sides of the device are formed. The excessive power dissipation in the dominant filament causes failure and permanent damage.
Solid-State Electronics, 1986
Journal of Applied Physics, 1994
Recent articles have been published claiming that the ambipolar diffusion coefficient of semicond... more Recent articles have been published claiming that the ambipolar diffusion coefficient of semiconductors, D(sub a), is basically independent of the excess-carrier concentration, thus contradicting the conventional result of, for example, Fletcher. However, only a few experimentally verified papers on this subject are published. In the present work, a detailed experimental analysis of the ambipolar diffusion coefficient is presented regarding both
Journal of Applied Physics, 1996
Using three measurement techniques the injection and temperature dependence of the Shockley–Read–... more Using three measurement techniques the injection and temperature dependence of the Shockley–Read–Hall (SRH) carrier lifetime was studied. Flying-spot scanning was used for the measurement of lifetimes under low-level injection. Open-circuit carrier decay for the measurement of high-injection lifetime, and deep-level transient spectroscopy for the characterization of active recombination centers. The samples were silicon p-i-n type diodes (p+-n-n+) irradiated with 15 MeV electrons for lifetime control. The measurements consistently show that two defect levels located at Ec−0.164 eV (E1) correlated to the vacancy-oxygen complex and Ec−0.421 eV (E4) correlated to the single-negatively charged state of the divacancy are significant for the SRH lifetime in different injection domains in the low-doped n-type region. The E1 recombination center is dominating the high-injection lifetime and the E4 center is dominating the low-injection lifetime. Similar to other authors, additional defect levels have also been observed, but the E1 and E4 levels seem sufficient to explain the behavior of electron-irradiated semiconductor power devices.
IEEE Transactions on Instrumentation and Measurement, 1990
The measurement of two-dimensional (2-D) excess-carrier distribution in a gate GTO by a time-reso... more The measurement of two-dimensional (2-D) excess-carrier distribution in a gate GTO by a time-resolved infrared-absorption technique is discussed. The optical scanning system employs a wide memory digital oscilloscope for data acquisition and a computer system for control, data processing, and display. Maps of the carrier distribution in the active GTO device are produced under steady-state conditions as well as during
IEEE Transactions on Instrumentation and Measurement, 1991
IEEE Transactions on Electron Devices, 1994
The free-carrier absorption (FCA) technique is used for mapping of the carrier content in a dual-... more The free-carrier absorption (FCA) technique is used for mapping of the carrier content in a dual-cathode gate turnoff thyristor (GTO) at different stages of the turn-off cycle. The FCA technique outputs 3-D maps based on 2-D measurements of local carrier concentration. The measurements are time resolved, thus making a transient response converted into a corresponding sequence of carrier maps. The dual-cathode device is shown to be sufficient for determining the transient behavior in a multicathode structure. The destruction mechanism and reasons for turn-off failure are investigated. The GTO device is inductively loaded and asymmetrically gate contacted in order to emulate a realistic mode of operation. The gate-driving conditions are altered, and the importance of the turn-off gain for turn-off failure is established. The case of equal ON-state cathode currents in both segments is particularly highlighted. The influence of snubber circuits is also discussed.
IEEE Transactions on Electron Devices, 1995
The influence of the anode shorting on the turn-off failure of GTO thyristors is investigated. Tw... more The influence of the anode shorting on the turn-off failure of GTO thyristors is investigated. Two types of shorting patterns, viz., "fmger"-and "ring"-type anode designs, are compared with a non-shorted design. The inductively loaded GTO unit cells are measured under snubberless operation close to the safe-operating area (SOA) limit. The critical anode blocking voltage was obtained for a constant anode current density by varying the turn-off gain, G. The investigation has shown that the turn-off voltage capability of both types of anode-shorted GTO's is deteriorated for high G values. The "ring"-type anode design, however, shows better voltage blocking capability than the "finger" type. This behavior is attributed to the formation of a cylindrical high drift-current density filament at the end of the storage and beginning of the fall-time periods. The electric field in this region, which is referred to as a quasi space-charge region (QSC), is strongly G dependent. Measurements based on the timeresolved free-carrier absorption (FCA) technique are used to map the carrier-density redistribution inside the unit cell during the turn-off switching cycle. For the first time, 3-D simulations of the GTO cell are also presented in order to support the model of dynamic punch-through failure at high G values, which was proposed in earlier papers.
IEEE Transactions on Electron Devices, 1993
A time-resolved free-carrier absorption technique is used to describe transient gate turn-off thy... more A time-resolved free-carrier absorption technique is used to describe transient gate turn-off thyristor (GTO) phenomena two-dimensionally . The measurements are spatially resolved in the anode-to-cathode direction, as well as in the direction determined by the cathode length. Effects associated with charge removal during the GTO turn-off cycle with respect to external circuit conditions are discussed. The behavior of resistively and inductively loaded GTO:s is explained on basis of experimental results. Modeled results, published by others, are used for comparison. VOBECKY et al: 2-D ANALYSIS OF TURN-OFF PROCESS IN GTO 2353.
IEEE Electron Device Letters, 2000
The MOS-controlled thyristor (MCT) is well suited for very high power applications. The maximum c... more The MOS-controlled thyristor (MCT) is well suited for very high power applications. The maximum capability of turn-off currents for p-channel MCT's was so far limited to low values (<10 A at 1000 V snubberless switching) due to strong sublinear current scaling with respect to the device area. In this letter we investigate this phenomenon by full device scale transient carrier
Membrane Technology, 1993
A well calibrated free-carrier absorption (FCA) technique was used to characterize the physical p... more A well calibrated free-carrier absorption (FCA) technique was used to characterize the physical properties of P-I-N diode samples at different temperatures and injection levels. The measurements were compared with simulations in order to check the validity of some models and parameters which commonly appear in the simulation programs. The samples, as well as measurement temperatures (30-150°C) and injection levels (1015-1017cm¿3),
Materials Science Forum, 2001
Proceedings of the 6th International Symposium on Power Semiconductor Devices and Ics, 1994
This paper discusses the importance of reliable physical models/parameters used in drift-diffusio... more This paper discusses the importance of reliable physical models/parameters used in drift-diffusion device simulation of power devices. Simple devices, diodes, and considerably more complicated structures, Gate Turn-off thyristors (GT0:s) have been investigated. Using both electrical and optical measurement techniques, comparisons have been made between measured data and simulated results. A proposal is made for new Auger recombination parameter values and for the temperature dependence of the Shockley-Read-Hall lifetime in the temperature range of 300-450 K.
52nd Annual Device Research Conference, 1994
Proceedings of 9th International Symposium on Power Semiconductor Devices and IC's, 1997
A tandem accelerator has been used to simulate the effect of cosmic rays on the DC stability prop... more A tandem accelerator has been used to simulate the effect of cosmic rays on the DC stability properties of a reverse biased pn diode. 30 MeV Carbon ions, with a maximum ionization of 130 eV/Å, were stopped in a reverse biased pn-junction. If the electric field is high enough, the large number of electron-hole pairs created by the ions results
Proceedings of the 13th International Symposium on Power Semiconductor Devices & ICs. IPSD '01 (IEEE Cat. No.01CH37216), 2001
4H-SiC diodes with 4.5 kV blocking and epitaxially grown anode emitters show near theoretical for... more 4H-SiC diodes with 4.5 kV blocking and epitaxially grown anode emitters show near theoretical forward voltages of 3.08 V at 100 A/cm 2 and 4.10 V at 1000 A/cm2 at RT (2.96 V and 4.15 V at 125°C), while diodes with implanted emitters show 3.5-3.8 V at 100 A/cm2 with -4 mV/K. The transient recovery losses (Erec, Qrr) are as low as 1/100 of the reference silicon device. Paralleling of the SiC diodes with silicon IGBTs enables 400 A switching, and system loss savings of nearly 50% compared to state-of-art silicon technology
Materials Science Forum, 2002
ABSTRACT