The channel lateral pocket or halo region of NMOSFET characterized by interface state R G current of a forward gated diode has been investigated numerically for the first time.The result of numerical analysis demons...The channel lateral pocket or halo region of NMOSFET characterized by interface state R G current of a forward gated diode has been investigated numerically for the first time.The result of numerical analysis demonstrates that the effective surface doping concentration and the interface state density of the pocket or halo region are interface states R G current peak position dependent and amplitude dependent,respectively.It can be expressed quantitatively according to the device physics knowledge,thus,the direct characterization of the interface state density and the effective surface doping concentration of the pocket or halo becomes very easy.展开更多
AlAs/GaAs/In0.1Ga0.9As/GaAs/AlAs double-barrier resonant tunneling diodes （DBRTDs） grown on a semi-insulated GaAs substrate with molecular beam epitaxy is demonstrated. By sandwiching the In0.1 Ga0.9 As layer betwee...AlAs/GaAs/In0.1Ga0.9As/GaAs/AlAs double-barrier resonant tunneling diodes （DBRTDs） grown on a semi-insulated GaAs substrate with molecular beam epitaxy is demonstrated. By sandwiching the In0.1 Ga0.9 As layer between GaAs layers, potential wells beside the two sides of barrier are deepened, resulting in an increase of the peak-to-valley current ratio （PVCR） and a peak current density. A special shape of collector is designed in order to reduce contact resistance and non-uniformity of the current;as a result the total chrrent density in the device is increased. The use of thin barriers is also helpful for the improvement of the PVCR and the peak current density in DBRTDs. The devices exhibit a maximum PVCR of 13.98 and a peak current density of 89kA/cm^2 at room temperature.展开更多
Forward gated-diode Recombination-Generation(R-G) current method is applied to an NMOSFET/SOI to measure the stress-induced interface traps in this letter. This easy but accurate experimental method can directly give ...Forward gated-diode Recombination-Generation(R-G) current method is applied to an NMOSFET/SOI to measure the stress-induced interface traps in this letter. This easy but accurate experimental method can directly give stress-induced average interface traps for characterizing the device’s hot carrier characteristics. For the tested device, an expected power law relationship of △Nit-t0.787 between pure stress-induced interface traps and accumulated stressing time is obtained.展开更多
Light detection and ranging (LIDAR) based on time of flight (TOF) method is widely used in many fields related to distance measurement. LIDAR generally uses laser diode (LD) to emit the pulsed laser with high peak pow...Light detection and ranging (LIDAR) based on time of flight (TOF) method is widely used in many fields related to distance measurement. LIDAR generally uses laser diode (LD) to emit the pulsed laser with high peak power and short duration to ensure a large distance measurement range and eye safety. To achieve this goal, we propose a pulsed LD drive method producing the drive current with high peak and narrow pulse width. We analyze the key issues and related theories of the drive current generation based on this method and design an LD driver. A model of drive current generation is established and the influence of operating frequency on drive current is discussed. The LD driver is simulated by software and verified by experiments. The working frequency of the driver changes from 20 kHz to 100 kHz and the charging voltage is set at 130 V. The current produced by this driver has a duration of 8.8 ns and a peak of about 35 A, and the peak output optical power of the LD exceeds 75 W.展开更多
This paper proposes a control method for avalanche photodiode(APD) reverse bias with temperature compensation and load resistance compensation. The influence of background light and load resistance on APD detection ci...This paper proposes a control method for avalanche photodiode(APD) reverse bias with temperature compensation and load resistance compensation. The influence of background light and load resistance on APD detection circuit is analyzed in detail. A theoretical model of temperature compensation and load resistance compensation is established,which is used for APD biasing circuit designing. It is predicted that this control method is especially suitable for LD laser range finder used on vehicles. Experimental results confirm that the design proposed in this paper can considerablely improve the performance of range finder.展开更多
As the quality of power LED improves and the cost of power LED reduces, semiconductor lighting will replace incandescent and fluorescent lighting gradually, causing another revolution on the lighting history. And its ...As the quality of power LED improves and the cost of power LED reduces, semiconductor lighting will replace incandescent and fluorescent lighting gradually, causing another revolution on the lighting history. And its driving solution has been greatly accelerated. Based on the white power LED I-V characteristics and the application ambiance, proposed is a new LED lighting solution, suiting indoor and outdoor illumination. According to the test results, the design is optimized, and the electrical efficiency is 95% and the output current deviation is 13.0%.展开更多
A new dimmer using a mental-oxide-semiconductor field-effect transistor (MOSFET) for alternating-current (AC) directly driven light-emitting-diode (LED) lamp was presented. The control method of proposed dimmer is pul...A new dimmer using a mental-oxide-semiconductor field-effect transistor (MOSFET) for alternating-current (AC) directly driven light-emitting-diode (LED) lamp was presented. The control method of proposed dimmer is pulse width control (PWM) method. Compared with the conventional phase-controlled dimmer, the proposed PWM dimmer can produce sine wave and did not cause harmonics problem. Furthermore, the proposed control method did not amplify the light flicker due to the independence of input voltage. Therefore, the PWM dimmer can be used as the dimmer of the AC LED lamp instead of the conventional phase-controlled dimmer. The experimental result shows that the proposed PWM dimmer has good performances.展开更多
An accurate photodiode circuit macro-model is proposed for SPICE simulation. The definition and implementation of the macro-model is based on carrier stationary continuity equation. In this macro-model, the photodiode...An accurate photodiode circuit macro-model is proposed for SPICE simulation. The definition and implementation of the macro-model is based on carrier stationary continuity equation. In this macro-model, the photodiode is a device of three pins, one for light intensity input and the other two for photocurrent output, which represent the relationship between photocurrent and incident light. The validity of the proposed macro-model is demonstrated with its PSPICE simulation result compared with reported experimental data.展开更多
The dark current of In_(0.47) Ga_(0.53) As/InP heterojunction photodiodes (HPDs) was analysed. We found that there exists a new dark current component──deep level-assisted tunnelling current.DLTS was used to measure...The dark current of In_(0.47) Ga_(0.53) As/InP heterojunction photodiodes (HPDs) was analysed. We found that there exists a new dark current component──deep level-assisted tunnelling current.DLTS was used to measure the In_(0.47)Ga_(0.53)As/InP HPDs. An electronic trap which has a thermal activation energy of O.44 eV, level concentration of 3.10×10￣(13)cm￣(-3) and electronic capture cross section of 1.72×10￣(12)cm￣2 has been found.It's existence results in the new tunnelling current.展开更多
文摘The channel lateral pocket or halo region of NMOSFET characterized by interface state R G current of a forward gated diode has been investigated numerically for the first time.The result of numerical analysis demonstrates that the effective surface doping concentration and the interface state density of the pocket or halo region are interface states R G current peak position dependent and amplitude dependent,respectively.It can be expressed quantitatively according to the device physics knowledge,thus,the direct characterization of the interface state density and the effective surface doping concentration of the pocket or halo becomes very easy.
文摘AlAs/GaAs/In0.1Ga0.9As/GaAs/AlAs double-barrier resonant tunneling diodes （DBRTDs） grown on a semi-insulated GaAs substrate with molecular beam epitaxy is demonstrated. By sandwiching the In0.1 Ga0.9 As layer between GaAs layers, potential wells beside the two sides of barrier are deepened, resulting in an increase of the peak-to-valley current ratio （PVCR） and a peak current density. A special shape of collector is designed in order to reduce contact resistance and non-uniformity of the current;as a result the total chrrent density in the device is increased. The use of thin barriers is also helpful for the improvement of the PVCR and the peak current density in DBRTDs. The devices exhibit a maximum PVCR of 13.98 and a peak current density of 89kA/cm^2 at room temperature.
基金Sponsored by Motorola-Peking University Joint Project.Contract No.:MSPSDDLCHINA-0004
文摘Forward gated-diode Recombination-Generation(R-G) current method is applied to an NMOSFET/SOI to measure the stress-induced interface traps in this letter. This easy but accurate experimental method can directly give stress-induced average interface traps for characterizing the device’s hot carrier characteristics. For the tested device, an expected power law relationship of △Nit-t0.787 between pure stress-induced interface traps and accumulated stressing time is obtained.
基金National Key Research and Development Plan(No.2017YFF0204800)Natural Science Foundation of Tianjin(No.17JCQNJC01100)+3 种基金National Natural Science Foundation of China(Nos.61501319,51775377,61505140)Young Elite Scientists Sponsorship Program by Cast of China(No.2016QNRC001)Open Project of Key Laboratory of Micro Opto-electro Mechanical System Technology(No.MOMST2015-7)Open Project from Photoelectric Information and Instrument-Engineering Research Center of Beijing,Tianjin University,Ministry of Education(No.GD2015007)
文摘Light detection and ranging (LIDAR) based on time of flight (TOF) method is widely used in many fields related to distance measurement. LIDAR generally uses laser diode (LD) to emit the pulsed laser with high peak power and short duration to ensure a large distance measurement range and eye safety. To achieve this goal, we propose a pulsed LD drive method producing the drive current with high peak and narrow pulse width. We analyze the key issues and related theories of the drive current generation based on this method and design an LD driver. A model of drive current generation is established and the influence of operating frequency on drive current is discussed. The LD driver is simulated by software and verified by experiments. The working frequency of the driver changes from 20 kHz to 100 kHz and the charging voltage is set at 130 V. The current produced by this driver has a duration of 8.8 ns and a peak of about 35 A, and the peak output optical power of the LD exceeds 75 W.
文摘This paper proposes a control method for avalanche photodiode(APD) reverse bias with temperature compensation and load resistance compensation. The influence of background light and load resistance on APD detection circuit is analyzed in detail. A theoretical model of temperature compensation and load resistance compensation is established,which is used for APD biasing circuit designing. It is predicted that this control method is especially suitable for LD laser range finder used on vehicles. Experimental results confirm that the design proposed in this paper can considerablely improve the performance of range finder.
文摘As the quality of power LED improves and the cost of power LED reduces, semiconductor lighting will replace incandescent and fluorescent lighting gradually, causing another revolution on the lighting history. And its driving solution has been greatly accelerated. Based on the white power LED I-V characteristics and the application ambiance, proposed is a new LED lighting solution, suiting indoor and outdoor illumination. According to the test results, the design is optimized, and the electrical efficiency is 95% and the output current deviation is 13.0%.
文摘A new dimmer using a mental-oxide-semiconductor field-effect transistor (MOSFET) for alternating-current (AC) directly driven light-emitting-diode (LED) lamp was presented. The control method of proposed dimmer is pulse width control (PWM) method. Compared with the conventional phase-controlled dimmer, the proposed PWM dimmer can produce sine wave and did not cause harmonics problem. Furthermore, the proposed control method did not amplify the light flicker due to the independence of input voltage. Therefore, the PWM dimmer can be used as the dimmer of the AC LED lamp instead of the conventional phase-controlled dimmer. The experimental result shows that the proposed PWM dimmer has good performances.
基金National Natural Science Foundation of China(30470469)
文摘An accurate photodiode circuit macro-model is proposed for SPICE simulation. The definition and implementation of the macro-model is based on carrier stationary continuity equation. In this macro-model, the photodiode is a device of three pins, one for light intensity input and the other two for photocurrent output, which represent the relationship between photocurrent and incident light. The validity of the proposed macro-model is demonstrated with its PSPICE simulation result compared with reported experimental data.
文摘The dark current of In_(0.47) Ga_(0.53) As/InP heterojunction photodiodes (HPDs) was analysed. We found that there exists a new dark current component──deep level-assisted tunnelling current.DLTS was used to measure the In_(0.47)Ga_(0.53)As/InP HPDs. An electronic trap which has a thermal activation energy of O.44 eV, level concentration of 3.10×10￣(13)cm￣(-3) and electronic capture cross section of 1.72×10￣(12)cm￣2 has been found.It's existence results in the new tunnelling current.
