Partial-depleted SOI(silicon on insulator) nMOS devices are fabricated with and without silicide technology,respectively.Off-state breakdown characteristics of these devices are presented with and without body contact...Partial-depleted SOI(silicon on insulator) nMOS devices are fabricated with and without silicide technology,respectively.Off-state breakdown characteristics of these devices are presented with and without body contact,respectively.By means of two-dimension(2D) device simulation and measuring junction breakdown of the drain and the body,the difference and limitation of the breakdown characteristics of devices with two technologies are analyzed and explained in details.Based on this,a method is proposed to improve off-state breakdown characteristics of PDSOI nMOS devices.展开更多
Partially-depleted silicon-on-insulator(PDSOI)floating-body(FB)nMOSFETs and H-gate type body-contacted(BC)nMOSFETs are fabricated with different back channel implantation dosages. The off-state breakdown charact...Partially-depleted silicon-on-insulator(PDSOI)floating-body(FB)nMOSFETs and H-gate type body-contacted(BC)nMOSFETs are fabricated with different back channel implantation dosages. The off-state breakdown characteristics of these devices are presented. The off-state breakdown voltages of the FB nMOSFETs increase from 5.2 to 6. 7V, and those of the H-gate type BC nMOSFETs decrease from 11.9 to 9V as the back channel implantation dosages increase from 1.0 ×10^13 to 1.3×10^13 cm^-2. By measuring the parasitic bipolar transistor static gain and the breakdown characteristics of the pn junction between the drain and the body, the differences between the breakdown mechanisms of the FB and H-gate type BC nMOSFETs are analyzed and explained qualitatively.展开更多
A new SOI (Silicon On Insulator) high voltage device with Step Unmovable Surface Charges (SUSC) of buried oxide layer and its analytical breakdown model are proposed in the paper. The unmovable charges are impleme...A new SOI (Silicon On Insulator) high voltage device with Step Unmovable Surface Charges (SUSC) of buried oxide layer and its analytical breakdown model are proposed in the paper. The unmovable charges are implemented into the upper surface of buried oxide layer to increase the vertical electric field and uniform the lateral one. The 2-D Poisson's equation is solved to demonstrate the modulation effect of the immobile interface charges and analyze the electric field and breakdown voltage with the various geometric parameters and step numbers. A new RESURF (REduce SURface Field) condition of the SOl device considering the interface charges and buried oxide is derived to maximize breakdown voltage. The analytical results are in good agreement with the numerical analysis obtained by the 2-D semiconductor devices simulator MEDICI. As a result, an 1200V breakdown voltage is firstly obtained in 3pro-thick top Si layer, 2pro-thick buried oxide layer and 70pro-length drift region using a linear doping profile of unmovable buried oxide charges.展开更多
Breakdown formation in an explosive-emission electron source is related to the interelectrode gap filling with plasma propagating from the cathode and formed at the anode and in the interelectrode gap under the electr...Breakdown formation in an explosive-emission electron source is related to the interelectrode gap filling with plasma propagating from the cathode and formed at the anode and in the interelectrode gap under the electron beam action. Plasma anode is used to increase the beam current density. Preliminary interelectrode gap filling with plasma in the explosive-emission source decreases the influence of uncontrolled plasma arrival from the anode on the diode processes, promotes current density increase and duration of generated electron beams. The paper considers the influence of the cathode geometry on the breakdown formation in the plasma-anode explosive-emission electron source. The data on obtaining of microsecond electron beams with current density of 30 A/cm^2 and 1.5-2 kA/cm^2 are presented.展开更多
In the present work, Laser induced Breakdown spectroscopy technique is used to investigate the laser induced plasma of PMMA in air. The optical emission of PMMA plasma is found quite intense and dominated by vibration...In the present work, Laser induced Breakdown spectroscopy technique is used to investigate the laser induced plasma of PMMA in air. The optical emission of PMMA plasma is found quite intense and dominated by vibrational band of CN molecules (violet band, B^2∑^+ - X^2∑^+) at 388.4 nm. The temporal response of the CN band emission is studied and found decay time 22 ns. The low decay time and small laser spot (34 × 32 μm^2) conf'n-ms good thermal stability of PMMA. To get structural fingerprint of PMMA, Raman spectrum is recorded prior to the exposure to laser. Several sharp Raman peaks have been observed along with a very intense peak at 2,957 cm1 attributed to C-H stretching vibration. Post exposure Raman spectrum is also recorded to analyze the heating effect and re-deposition of ablated material.展开更多
Breakdown formation in the explosive-emission sources is related to the interelectrode gap filling with the cathode and anode plasma generated at the anode and in the gap under the beam influence. Under conditions of ...Breakdown formation in the explosive-emission sources is related to the interelectrode gap filling with the cathode and anode plasma generated at the anode and in the gap under the beam influence. Under conditions of saturation of the cathode plasma emissive ability as well as when the measures on the emission boundary stabilization are taken, the anode plasma has the deciding part in the formation of the electron source breakdown. The paper presents the results of the anode plasma investigations obtained to solve the problem of the electron beam length increase in the explosive-emission sources. The data concerning the gas release from the anode, the mechanism of the anode plasma formation and the anode plasma influence on the parameters of the generated electron beam are presented as well.展开更多
MMT (modified magnetron typed) plasma nitridation and NO anneal are used to treat ultra-thin gate oxides in MOSFETs (metal-oxide-semiconductor field effect transistors). Dual-peak and single-peak N distributions a...MMT (modified magnetron typed) plasma nitridation and NO anneal are used to treat ultra-thin gate oxides in MOSFETs (metal-oxide-semiconductor field effect transistors). Dual-peak and single-peak N distributions are formed after nitridation. The dual-peak N distribution shows excellent electrical properties and superior reliability in terms of drain current,channel carrier mobility, and TDDB characteristics. The results indicate a means to extend silicon oxynitride as a promising gate dielectric for developing ultralarge scale integrated (ULSI) technology.展开更多
HfxAl(1-x)O film grown by atomic layer deposition(ALD) on n-type 4H-SiC(0001) epitaxial layer has been studied.Measurements show that it has relatively high breakdown electric field of 16.4 MV/cm,high dielectric const...HfxAl(1-x)O film grown by atomic layer deposition(ALD) on n-type 4H-SiC(0001) epitaxial layer has been studied.Measurements show that it has relatively high breakdown electric field of 16.4 MV/cm,high dielectric constant of 16.3 and low gate leakage current of 2.47×10-5 A/cm2 at E=5 MV/cm,which makes ALD HfxAl(1-x)O a great potential candidate gate dielectric for 4H-SiC MIS based transistors.展开更多
The effects of the ambient air pressure level on the performance of plasma synthetic jet actuator have been investigated through electrical and optical diagnostics.Pressures from 1 atm down to 0.1 atm were tested with...The effects of the ambient air pressure level on the performance of plasma synthetic jet actuator have been investigated through electrical and optical diagnostics.Pressures from 1 atm down to 0.1 atm were tested with a 10 Hz excitation.The discharge measurement demonstrates that there is a voltage range to make the actuator work reliably.Higher pressure level needs a higher breakdown voltage,and a higher discharge current and energy deposition are produced.But when the actuator works with the maximum breakdown voltage,the fraction of the initial capacitor energy delivered to the arc is almost invariable.This preliminary study also confirms the effectiveness of the plasma synthetic jet at low pressure.Indeed,the maximum velocities of the precursor shock and the plasma jet induced by the actuator with maximum breakdown voltage are independent of the ambient pressure level;reach about 530 and 460 m/s respectively.The mass flux of the plasma jet increases with ambient pressure increasing,but the strength of the precursor shock presents a local maximum at 0.6 atm.展开更多
基金Supported by National Natural Science Foundation of China (NSFC)(50438070)Program for New Century Excellent Talents in University of China (NCET-04-0095)Ph.D. Programs Foundation of Ministry of Education of China (200800030040)~~
文摘Partial-depleted SOI(silicon on insulator) nMOS devices are fabricated with and without silicide technology,respectively.Off-state breakdown characteristics of these devices are presented with and without body contact,respectively.By means of two-dimension(2D) device simulation and measuring junction breakdown of the drain and the body,the difference and limitation of the breakdown characteristics of devices with two technologies are analyzed and explained in details.Based on this,a method is proposed to improve off-state breakdown characteristics of PDSOI nMOS devices.
文摘Partially-depleted silicon-on-insulator(PDSOI)floating-body(FB)nMOSFETs and H-gate type body-contacted(BC)nMOSFETs are fabricated with different back channel implantation dosages. The off-state breakdown characteristics of these devices are presented. The off-state breakdown voltages of the FB nMOSFETs increase from 5.2 to 6. 7V, and those of the H-gate type BC nMOSFETs decrease from 11.9 to 9V as the back channel implantation dosages increase from 1.0 ×10^13 to 1.3×10^13 cm^-2. By measuring the parasitic bipolar transistor static gain and the breakdown characteristics of the pn junction between the drain and the body, the differences between the breakdown mechanisms of the FB and H-gate type BC nMOSFETs are analyzed and explained qualitatively.
基金Supported by the National Natural Science Foundation of China (No.60276040).
文摘A new SOI (Silicon On Insulator) high voltage device with Step Unmovable Surface Charges (SUSC) of buried oxide layer and its analytical breakdown model are proposed in the paper. The unmovable charges are implemented into the upper surface of buried oxide layer to increase the vertical electric field and uniform the lateral one. The 2-D Poisson's equation is solved to demonstrate the modulation effect of the immobile interface charges and analyze the electric field and breakdown voltage with the various geometric parameters and step numbers. A new RESURF (REduce SURface Field) condition of the SOl device considering the interface charges and buried oxide is derived to maximize breakdown voltage. The analytical results are in good agreement with the numerical analysis obtained by the 2-D semiconductor devices simulator MEDICI. As a result, an 1200V breakdown voltage is firstly obtained in 3pro-thick top Si layer, 2pro-thick buried oxide layer and 70pro-length drift region using a linear doping profile of unmovable buried oxide charges.
文摘Breakdown formation in an explosive-emission electron source is related to the interelectrode gap filling with plasma propagating from the cathode and formed at the anode and in the interelectrode gap under the electron beam action. Plasma anode is used to increase the beam current density. Preliminary interelectrode gap filling with plasma in the explosive-emission source decreases the influence of uncontrolled plasma arrival from the anode on the diode processes, promotes current density increase and duration of generated electron beams. The paper considers the influence of the cathode geometry on the breakdown formation in the plasma-anode explosive-emission electron source. The data on obtaining of microsecond electron beams with current density of 30 A/cm^2 and 1.5-2 kA/cm^2 are presented.
文摘In the present work, Laser induced Breakdown spectroscopy technique is used to investigate the laser induced plasma of PMMA in air. The optical emission of PMMA plasma is found quite intense and dominated by vibrational band of CN molecules (violet band, B^2∑^+ - X^2∑^+) at 388.4 nm. The temporal response of the CN band emission is studied and found decay time 22 ns. The low decay time and small laser spot (34 × 32 μm^2) conf'n-ms good thermal stability of PMMA. To get structural fingerprint of PMMA, Raman spectrum is recorded prior to the exposure to laser. Several sharp Raman peaks have been observed along with a very intense peak at 2,957 cm1 attributed to C-H stretching vibration. Post exposure Raman spectrum is also recorded to analyze the heating effect and re-deposition of ablated material.
文摘Breakdown formation in the explosive-emission sources is related to the interelectrode gap filling with the cathode and anode plasma generated at the anode and in the gap under the beam influence. Under conditions of saturation of the cathode plasma emissive ability as well as when the measures on the emission boundary stabilization are taken, the anode plasma has the deciding part in the formation of the electron source breakdown. The paper presents the results of the anode plasma investigations obtained to solve the problem of the electron beam length increase in the explosive-emission sources. The data concerning the gas release from the anode, the mechanism of the anode plasma formation and the anode plasma influence on the parameters of the generated electron beam are presented as well.
文摘MMT (modified magnetron typed) plasma nitridation and NO anneal are used to treat ultra-thin gate oxides in MOSFETs (metal-oxide-semiconductor field effect transistors). Dual-peak and single-peak N distributions are formed after nitridation. The dual-peak N distribution shows excellent electrical properties and superior reliability in terms of drain current,channel carrier mobility, and TDDB characteristics. The results indicate a means to extend silicon oxynitride as a promising gate dielectric for developing ultralarge scale integrated (ULSI) technology.
基金supported by the National Natural Science Foundation of China (Grant No. 61006008)the National Defense Advance Research Project (Grant No. 513080301)the Key Specific Project in the National Sciences and Technology Program (Grant No. KJ080112501)
文摘HfxAl(1-x)O film grown by atomic layer deposition(ALD) on n-type 4H-SiC(0001) epitaxial layer has been studied.Measurements show that it has relatively high breakdown electric field of 16.4 MV/cm,high dielectric constant of 16.3 and low gate leakage current of 2.47×10-5 A/cm2 at E=5 MV/cm,which makes ALD HfxAl(1-x)O a great potential candidate gate dielectric for 4H-SiC MIS based transistors.
基金supported by the National Natural Science Foundation of China(Grant No.11372349)the Foundation for the Author of National Excellent Doctor Dissertation of China(Grant No.201058)the Nature Science Fund for Distinguished Young Scholars of National University of Defense Technology,China(Grant No.CJ110101)
文摘The effects of the ambient air pressure level on the performance of plasma synthetic jet actuator have been investigated through electrical and optical diagnostics.Pressures from 1 atm down to 0.1 atm were tested with a 10 Hz excitation.The discharge measurement demonstrates that there is a voltage range to make the actuator work reliably.Higher pressure level needs a higher breakdown voltage,and a higher discharge current and energy deposition are produced.But when the actuator works with the maximum breakdown voltage,the fraction of the initial capacitor energy delivered to the arc is almost invariable.This preliminary study also confirms the effectiveness of the plasma synthetic jet at low pressure.Indeed,the maximum velocities of the precursor shock and the plasma jet induced by the actuator with maximum breakdown voltage are independent of the ambient pressure level;reach about 530 and 460 m/s respectively.The mass flux of the plasma jet increases with ambient pressure increasing,but the strength of the precursor shock presents a local maximum at 0.6 atm.