In this paper,two-dimensional electron gas（2DEG） regions in AlGaN/GaN high electron mobility transistors（HEMTs） are realized by doping partial silicon into the AlGaN layer for the first time.A new electric field p...In this paper,two-dimensional electron gas（2DEG） regions in AlGaN/GaN high electron mobility transistors（HEMTs） are realized by doping partial silicon into the AlGaN layer for the first time.A new electric field peak is introduced along the interface between the AlGaN and GaN buffer by the electric field modulation effect due to partial silicon positive charge.The high electric field near the gate for the complete silicon doping structure is effectively decreased,which makes the surface electric field uniform.The high electric field peak near the drain results from the potential difference between the surface and the depletion regions.Simulated breakdown curves that are the same as the test results are obtained for the first time by introducing an acceptor-like trap into the N-type GaN buffer.The proposed structure with partial silicon doping is better than the structure with complete silicon doping and conventional structures with the electric field plate near the drain.The breakdown voltage is improved from 296 V for the conventional structure to 400 V for the proposed one resulting from the uniform surface electric field.展开更多
Electrical properties of an AIlnN/GaN high-electron mobility transistor （HEMT） on a sapphire substrate are investigated in a cryogenic temperature range from 295 K down to 50 K. It is shown that drain saturation cur...Electrical properties of an AIlnN/GaN high-electron mobility transistor （HEMT） on a sapphire substrate are investigated in a cryogenic temperature range from 295 K down to 50 K. It is shown that drain saturation current and conductance increase as transistor operation temperature decreases. A self-heating effect is observed over the entire range of temperature under high power consumption. The dependence of channel electron mobility on electron density is investigated in detail. It is found that aside from Coulomb scattering, electrons that have been pushed away from the AIInN/GaN interface into the bulk GaN substrate at a large reverse gate voltage are also responsible for the electron mobility drop with the decrease of electron density.展开更多
A physics-based analytical expression that predicts the charge,electrical field and potential distributions along the gated region of the GaN HEMT channel has been developed.Unlike the gradual channel approximation(GC...A physics-based analytical expression that predicts the charge,electrical field and potential distributions along the gated region of the GaN HEMT channel has been developed.Unlike the gradual channel approximation(GCA),the proposed model considers the non-uniform variation of the concentration under the gated region as a function of terminal applied volt-ages.In addition,the model can capture the influence of mobility and channel temperature on the charge distribution trend.The comparison with the hydrodynamic(HD)numerical simulation showed a high agreement of the proposed model with numerical data for different bias conditions considering the self-heating and quantization of the electron concentration.The ana-lytical nature of the model allows us to reduce the computational and time cost of the simulation.Also,it can be used as a core expression to develop a complete physics-based transistorⅣmodel without GCA limitation.展开更多
A new surface-potential-based model for A1GaN/A1N/GaN high electron mobility transistor （HEMT） is proposed in this paper. Since the high polarization effects caused by AlN interlayer favorably influence the two dime...A new surface-potential-based model for A1GaN/A1N/GaN high electron mobility transistor （HEMT） is proposed in this paper. Since the high polarization effects caused by AlN interlayer favorably influence the two dimensional electron gas （2DEG） and scattering mechanisms, we first add spontaneous and piezoelectric charge terms to the source equation of surface-potential, and a mobility model for A1GaN/A1N/GaN HEMT is rewritten. Compared with TCAD simulations, the DC characteristics of A1GaN/AIN/GaN HEMT are faithfully reproduced by the new model.展开更多
基金Project supported by the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 61106076)
文摘In this paper,two-dimensional electron gas（2DEG） regions in AlGaN/GaN high electron mobility transistors（HEMTs） are realized by doping partial silicon into the AlGaN layer for the first time.A new electric field peak is introduced along the interface between the AlGaN and GaN buffer by the electric field modulation effect due to partial silicon positive charge.The high electric field near the gate for the complete silicon doping structure is effectively decreased,which makes the surface electric field uniform.The high electric field peak near the drain results from the potential difference between the surface and the depletion regions.Simulated breakdown curves that are the same as the test results are obtained for the first time by introducing an acceptor-like trap into the N-type GaN buffer.The proposed structure with partial silicon doping is better than the structure with complete silicon doping and conventional structures with the electric field plate near the drain.The breakdown voltage is improved from 296 V for the conventional structure to 400 V for the proposed one resulting from the uniform surface electric field.
基金Project supported by the National Natural Science Foundation of China (Grant No. 61204018)
文摘Electrical properties of an AIlnN/GaN high-electron mobility transistor （HEMT） on a sapphire substrate are investigated in a cryogenic temperature range from 295 K down to 50 K. It is shown that drain saturation current and conductance increase as transistor operation temperature decreases. A self-heating effect is observed over the entire range of temperature under high power consumption. The dependence of channel electron mobility on electron density is investigated in detail. It is found that aside from Coulomb scattering, electrons that have been pushed away from the AIInN/GaN interface into the bulk GaN substrate at a large reverse gate voltage are also responsible for the electron mobility drop with the decrease of electron density.
基金This work was supported by the National Natural Science Foundation of China(NSFC)under Grant 61774141.
文摘A physics-based analytical expression that predicts the charge,electrical field and potential distributions along the gated region of the GaN HEMT channel has been developed.Unlike the gradual channel approximation(GCA),the proposed model considers the non-uniform variation of the concentration under the gated region as a function of terminal applied volt-ages.In addition,the model can capture the influence of mobility and channel temperature on the charge distribution trend.The comparison with the hydrodynamic(HD)numerical simulation showed a high agreement of the proposed model with numerical data for different bias conditions considering the self-heating and quantization of the electron concentration.The ana-lytical nature of the model allows us to reduce the computational and time cost of the simulation.Also,it can be used as a core expression to develop a complete physics-based transistorⅣmodel without GCA limitation.
基金supported by the Major State Basic Research Development Program of China(No.2010CB327403)the Zhejiang Provincial Key Science and Technology Innovation Team(No.Gk110908002)the National Science Foundation of China(No.61102027)
文摘A new surface-potential-based model for A1GaN/A1N/GaN high electron mobility transistor （HEMT） is proposed in this paper. Since the high polarization effects caused by AlN interlayer favorably influence the two dimensional electron gas （2DEG） and scattering mechanisms, we first add spontaneous and piezoelectric charge terms to the source equation of surface-potential, and a mobility model for A1GaN/A1N/GaN HEMT is rewritten. Compared with TCAD simulations, the DC characteristics of A1GaN/AIN/GaN HEMT are faithfully reproduced by the new model.
