The Experts below are selected from a list of 39393 Experts worldwide ranked by ideXlab platform
J W Palmour - One of the best experts on this subject based on the ideXlab platform.
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specific features of the switch on gate current and different switch on modes in silicon carbide Thyristors
Semiconductor Science and Technology, 2014Co-Authors: S N Yurkov, T T Mnatsakanov, M E Levinshtein, Lin Cheng, J W PalmourAbstract:The specific features of the temperature and bias dependences of the switch-on gate current in SiC Thyristors are examined analytically for two possible switching mechanisms. The so-called ?-mechanism, which is highly typical of the conventional Si Thyristors, is characterized by very weak temperature and bias dependences. By contrast, the so-called ?-mechanism, which is very characteristic of SiC Thyristors, is highly sensitive to changes in temperature and bias. If the thyristor is switched on by the ?-mechanism, the switch-on gate current density decreases very steeply with increasing temperature. As a result, the thyristor can lose its working capacity at elevated temperatures due to the instability against even very weak impacts. With decreasing the bias voltage Ua, the gate switch-on current increases very steeply, which can make switching the thyristor on difficult. The unintentional shunting, which is apparently present in high-voltage SiC Thyristors, causes the transition from the ?- to the ?-mechanism at elevated temperatures and high biases. It can be supposed that introduction of a controllable technological shunting of the emitter?thin base junction allows stabilization of the temperature and bias parameters of SiC Thyristors. The analytical results are confirmed by computer simulations performed in wide temperature and bias ranges for a 4H-SiC thyristor of the 18 kV class.
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optical triggering of high voltage 18 kv class 4h sic Thyristors
Semiconductor Science and Technology, 2013Co-Authors: M E Levinshtein, Lin Cheng, S L Rumyantsev, M S Shur, Anant K Agarwal, J W PalmourAbstract:Optical triggering of high-voltage (18 kV-class) 4H-SiC Thyristors with a single amplification step (pilot thyristor) is reported. It is demonstrated that the switch-on processes in such high-voltage structures are quite different from the switch-on processes in 12 kV 4H-SiC Thyristors. In particular, the switch-on process occurs in two stages even at maximum light pulse energy and rather high anode biases.
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holding current and switch on mechanisms in 12 kv 100 a 4h sic optically triggered Thyristors
Semiconductor Science and Technology, 2013Co-Authors: M E Levinshtein, S N Yurkov, T T Mnatsakanov, Lin Cheng, S L Rumyantsev, M S Shur, Qing Chun Jon Zhang, Anant K Agarwal, J W PalmourAbstract:Temperature dependence of the holding current has been studied in high-voltage (12?kV class) 4H-SiC optically triggered Thyristors in the temperature range from 300 to 425?K. The holding current Ih?monotonically decreases with increasing temperature T due to two factors: enhanced thermal ionization of comparatively deep Al acceptors in the p+?emitter and increasing carrier lifetime in the blocking p base. The Ih(T) dependence reveals the existence of a ?weak point? within the optical window, which is characterized by a substantially smaller critical charge than that within the remaining part of the window. Analysis of the Ih(T) dependence confirms that high-voltage SiC Thyristors are switched-on at room temperature only at a high injection level in the blocking base. At elevated temperatures, the same thyristor is switched on by the ?classical? mechanism typical of Si Thyristors. Effective shunting of the p++?n emitter junction affects the properties of the thyristor. Possible effective-shunting mechanisms are discussed.
M E Levinshtein - One of the best experts on this subject based on the ideXlab platform.
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specific features of the switch on gate current and different switch on modes in silicon carbide Thyristors
Semiconductor Science and Technology, 2014Co-Authors: S N Yurkov, T T Mnatsakanov, M E Levinshtein, Lin Cheng, J W PalmourAbstract:The specific features of the temperature and bias dependences of the switch-on gate current in SiC Thyristors are examined analytically for two possible switching mechanisms. The so-called ?-mechanism, which is highly typical of the conventional Si Thyristors, is characterized by very weak temperature and bias dependences. By contrast, the so-called ?-mechanism, which is very characteristic of SiC Thyristors, is highly sensitive to changes in temperature and bias. If the thyristor is switched on by the ?-mechanism, the switch-on gate current density decreases very steeply with increasing temperature. As a result, the thyristor can lose its working capacity at elevated temperatures due to the instability against even very weak impacts. With decreasing the bias voltage Ua, the gate switch-on current increases very steeply, which can make switching the thyristor on difficult. The unintentional shunting, which is apparently present in high-voltage SiC Thyristors, causes the transition from the ?- to the ?-mechanism at elevated temperatures and high biases. It can be supposed that introduction of a controllable technological shunting of the emitter?thin base junction allows stabilization of the temperature and bias parameters of SiC Thyristors. The analytical results are confirmed by computer simulations performed in wide temperature and bias ranges for a 4H-SiC thyristor of the 18 kV class.
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optical triggering of high voltage 18 kv class 4h sic Thyristors
Semiconductor Science and Technology, 2013Co-Authors: M E Levinshtein, Lin Cheng, S L Rumyantsev, M S Shur, Anant K Agarwal, J W PalmourAbstract:Optical triggering of high-voltage (18 kV-class) 4H-SiC Thyristors with a single amplification step (pilot thyristor) is reported. It is demonstrated that the switch-on processes in such high-voltage structures are quite different from the switch-on processes in 12 kV 4H-SiC Thyristors. In particular, the switch-on process occurs in two stages even at maximum light pulse energy and rather high anode biases.
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holding current and switch on mechanisms in 12 kv 100 a 4h sic optically triggered Thyristors
Semiconductor Science and Technology, 2013Co-Authors: M E Levinshtein, S N Yurkov, T T Mnatsakanov, Lin Cheng, S L Rumyantsev, M S Shur, Qing Chun Jon Zhang, Anant K Agarwal, J W PalmourAbstract:Temperature dependence of the holding current has been studied in high-voltage (12?kV class) 4H-SiC optically triggered Thyristors in the temperature range from 300 to 425?K. The holding current Ih?monotonically decreases with increasing temperature T due to two factors: enhanced thermal ionization of comparatively deep Al acceptors in the p+?emitter and increasing carrier lifetime in the blocking p base. The Ih(T) dependence reveals the existence of a ?weak point? within the optical window, which is characterized by a substantially smaller critical charge than that within the remaining part of the window. Analysis of the Ih(T) dependence confirms that high-voltage SiC Thyristors are switched-on at room temperature only at a high injection level in the blocking base. At elevated temperatures, the same thyristor is switched on by the ?classical? mechanism typical of Si Thyristors. Effective shunting of the p++?n emitter junction affects the properties of the thyristor. Possible effective-shunting mechanisms are discussed.
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on the homogeneity of the turn on process in high voltage 4h sic Thyristors
Solid-state Electronics, 2005Co-Authors: M E Levinshtein, Anant K Agarwal, P A Ivanov, John W PalmourAbstract:Abstract The homogeneity of the turn-on process in high-voltage 4H–SiC Thyristors has been investigated for the first time. It is shown that, even at the holding current, which is the minimum possible current at which the thyristor is still turned on, the on-state occupies the whole area of the thyristor. During the turn-on transient, the current density distribution may be virtually homogeneous even at the turn-on front up to a current density of 1600 A/cm 2 .
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current rise time constants in switch on process of sic Thyristors
Solid-state Electronics, 2002Co-Authors: T T Mnatsakanov, S N Yurkov, M E Levinshtein, P A Ivanov, John W Palmour, A G Tandoev, Anant K AgarwalAbstract:Abstract An analytical approach to analysis of the switch-on process in silicon carbide (SiC) Thyristors is taken. Expressions for the current rise time are obtained for both low, τ rL , and high injection levels, τ rH , in the blocking p 0 -base of a thyristor, with account taken of the fact that the injection coefficient of the SiC p + n-junction is less than unity. It is shown that in 4H-SiC Thyristors the τ rL / τ rH ratio may be as high as 25–30. The results obtained are in agreement with the available experimental data and computer simulations.
Anant K Agarwal - One of the best experts on this subject based on the ideXlab platform.
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optical triggering of high voltage 18 kv class 4h sic Thyristors
Semiconductor Science and Technology, 2013Co-Authors: M E Levinshtein, Lin Cheng, S L Rumyantsev, M S Shur, Anant K Agarwal, J W PalmourAbstract:Optical triggering of high-voltage (18 kV-class) 4H-SiC Thyristors with a single amplification step (pilot thyristor) is reported. It is demonstrated that the switch-on processes in such high-voltage structures are quite different from the switch-on processes in 12 kV 4H-SiC Thyristors. In particular, the switch-on process occurs in two stages even at maximum light pulse energy and rather high anode biases.
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holding current and switch on mechanisms in 12 kv 100 a 4h sic optically triggered Thyristors
Semiconductor Science and Technology, 2013Co-Authors: M E Levinshtein, S N Yurkov, T T Mnatsakanov, Lin Cheng, S L Rumyantsev, M S Shur, Qing Chun Jon Zhang, Anant K Agarwal, J W PalmourAbstract:Temperature dependence of the holding current has been studied in high-voltage (12?kV class) 4H-SiC optically triggered Thyristors in the temperature range from 300 to 425?K. The holding current Ih?monotonically decreases with increasing temperature T due to two factors: enhanced thermal ionization of comparatively deep Al acceptors in the p+?emitter and increasing carrier lifetime in the blocking p base. The Ih(T) dependence reveals the existence of a ?weak point? within the optical window, which is characterized by a substantially smaller critical charge than that within the remaining part of the window. Analysis of the Ih(T) dependence confirms that high-voltage SiC Thyristors are switched-on at room temperature only at a high injection level in the blocking base. At elevated temperatures, the same thyristor is switched on by the ?classical? mechanism typical of Si Thyristors. Effective shunting of the p++?n emitter junction affects the properties of the thyristor. Possible effective-shunting mechanisms are discussed.
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on the homogeneity of the turn on process in high voltage 4h sic Thyristors
Solid-state Electronics, 2005Co-Authors: M E Levinshtein, Anant K Agarwal, P A Ivanov, John W PalmourAbstract:Abstract The homogeneity of the turn-on process in high-voltage 4H–SiC Thyristors has been investigated for the first time. It is shown that, even at the holding current, which is the minimum possible current at which the thyristor is still turned on, the on-state occupies the whole area of the thyristor. During the turn-on transient, the current density distribution may be virtually homogeneous even at the turn-on front up to a current density of 1600 A/cm 2 .
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current rise time constants in switch on process of sic Thyristors
Solid-state Electronics, 2002Co-Authors: T T Mnatsakanov, S N Yurkov, M E Levinshtein, P A Ivanov, John W Palmour, A G Tandoev, Anant K AgarwalAbstract:Abstract An analytical approach to analysis of the switch-on process in silicon carbide (SiC) Thyristors is taken. Expressions for the current rise time are obtained for both low, τ rL , and high injection levels, τ rH , in the blocking p 0 -base of a thyristor, with account taken of the fact that the injection coefficient of the SiC p + n-junction is less than unity. It is shown that in 4H-SiC Thyristors the τ rL / τ rH ratio may be as high as 25–30. The results obtained are in agreement with the available experimental data and computer simulations.
S L Rumyantsev - One of the best experts on this subject based on the ideXlab platform.
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optical triggering of high voltage 18 kv class 4h sic Thyristors
Semiconductor Science and Technology, 2013Co-Authors: M E Levinshtein, Lin Cheng, S L Rumyantsev, M S Shur, Anant K Agarwal, J W PalmourAbstract:Optical triggering of high-voltage (18 kV-class) 4H-SiC Thyristors with a single amplification step (pilot thyristor) is reported. It is demonstrated that the switch-on processes in such high-voltage structures are quite different from the switch-on processes in 12 kV 4H-SiC Thyristors. In particular, the switch-on process occurs in two stages even at maximum light pulse energy and rather high anode biases.
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holding current and switch on mechanisms in 12 kv 100 a 4h sic optically triggered Thyristors
Semiconductor Science and Technology, 2013Co-Authors: M E Levinshtein, S N Yurkov, T T Mnatsakanov, Lin Cheng, S L Rumyantsev, M S Shur, Qing Chun Jon Zhang, Anant K Agarwal, J W PalmourAbstract:Temperature dependence of the holding current has been studied in high-voltage (12?kV class) 4H-SiC optically triggered Thyristors in the temperature range from 300 to 425?K. The holding current Ih?monotonically decreases with increasing temperature T due to two factors: enhanced thermal ionization of comparatively deep Al acceptors in the p+?emitter and increasing carrier lifetime in the blocking p base. The Ih(T) dependence reveals the existence of a ?weak point? within the optical window, which is characterized by a substantially smaller critical charge than that within the remaining part of the window. Analysis of the Ih(T) dependence confirms that high-voltage SiC Thyristors are switched-on at room temperature only at a high injection level in the blocking base. At elevated temperatures, the same thyristor is switched on by the ?classical? mechanism typical of Si Thyristors. Effective shunting of the p++?n emitter junction affects the properties of the thyristor. Possible effective-shunting mechanisms are discussed.
Lin Cheng - One of the best experts on this subject based on the ideXlab platform.
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specific features of the switch on gate current and different switch on modes in silicon carbide Thyristors
Semiconductor Science and Technology, 2014Co-Authors: S N Yurkov, T T Mnatsakanov, M E Levinshtein, Lin Cheng, J W PalmourAbstract:The specific features of the temperature and bias dependences of the switch-on gate current in SiC Thyristors are examined analytically for two possible switching mechanisms. The so-called ?-mechanism, which is highly typical of the conventional Si Thyristors, is characterized by very weak temperature and bias dependences. By contrast, the so-called ?-mechanism, which is very characteristic of SiC Thyristors, is highly sensitive to changes in temperature and bias. If the thyristor is switched on by the ?-mechanism, the switch-on gate current density decreases very steeply with increasing temperature. As a result, the thyristor can lose its working capacity at elevated temperatures due to the instability against even very weak impacts. With decreasing the bias voltage Ua, the gate switch-on current increases very steeply, which can make switching the thyristor on difficult. The unintentional shunting, which is apparently present in high-voltage SiC Thyristors, causes the transition from the ?- to the ?-mechanism at elevated temperatures and high biases. It can be supposed that introduction of a controllable technological shunting of the emitter?thin base junction allows stabilization of the temperature and bias parameters of SiC Thyristors. The analytical results are confirmed by computer simulations performed in wide temperature and bias ranges for a 4H-SiC thyristor of the 18 kV class.
-
optical triggering of high voltage 18 kv class 4h sic Thyristors
Semiconductor Science and Technology, 2013Co-Authors: M E Levinshtein, Lin Cheng, S L Rumyantsev, M S Shur, Anant K Agarwal, J W PalmourAbstract:Optical triggering of high-voltage (18 kV-class) 4H-SiC Thyristors with a single amplification step (pilot thyristor) is reported. It is demonstrated that the switch-on processes in such high-voltage structures are quite different from the switch-on processes in 12 kV 4H-SiC Thyristors. In particular, the switch-on process occurs in two stages even at maximum light pulse energy and rather high anode biases.
-
holding current and switch on mechanisms in 12 kv 100 a 4h sic optically triggered Thyristors
Semiconductor Science and Technology, 2013Co-Authors: M E Levinshtein, S N Yurkov, T T Mnatsakanov, Lin Cheng, S L Rumyantsev, M S Shur, Qing Chun Jon Zhang, Anant K Agarwal, J W PalmourAbstract:Temperature dependence of the holding current has been studied in high-voltage (12?kV class) 4H-SiC optically triggered Thyristors in the temperature range from 300 to 425?K. The holding current Ih?monotonically decreases with increasing temperature T due to two factors: enhanced thermal ionization of comparatively deep Al acceptors in the p+?emitter and increasing carrier lifetime in the blocking p base. The Ih(T) dependence reveals the existence of a ?weak point? within the optical window, which is characterized by a substantially smaller critical charge than that within the remaining part of the window. Analysis of the Ih(T) dependence confirms that high-voltage SiC Thyristors are switched-on at room temperature only at a high injection level in the blocking base. At elevated temperatures, the same thyristor is switched on by the ?classical? mechanism typical of Si Thyristors. Effective shunting of the p++?n emitter junction affects the properties of the thyristor. Possible effective-shunting mechanisms are discussed.