Analysis of electrostatic hydration free energies of the isomers of the 99mTc-BAT and 99mTc-DADT complexes is carried out using the computer simulation technique. The results show that not only a correlation exists be...Analysis of electrostatic hydration free energies of the isomers of the 99mTc-BAT and 99mTc-DADT complexes is carried out using the computer simulation technique. The results show that not only a correlation exists between the logarithm of the brain uptake and the electrostatic hydration free energy for the isomers of 99mTc-brain radiopharmaceu-ticals, but also a linear relationship exists between the logarithm of the ratio of the brain uptake of the syn isomer to that of the anti one and the difference between the electrostatic hydration free energy of the syn-isomer and that of the anti one. Furthermore, the investigation on the important factors influencing the brain uptakes of 99mTc-radiophar-maceuticals and the reasons of the different biodistribution of the isomers of the 99mTc-complexes is explored at the molecular level. The results may provide a reference for the rational drug design of brain imaging agents.展开更多
A novel polysilicon-assisted silicon-controlled rectifier （SCR） is presented and analyzed in this paper, which is fabricated in HHNEC＇s 0.18μm EEPROM process. The polysilicon-assisted SCRs take advantage of polysi...A novel polysilicon-assisted silicon-controlled rectifier （SCR） is presented and analyzed in this paper, which is fabricated in HHNEC＇s 0.18μm EEPROM process. The polysilicon-assisted SCRs take advantage of polysilicon layer to help bypass electro-static discharge （E S D） current without occupying extra layout area. TLP current-voltage （I-V） measurement results show that given the same layout areas, robustness performance of polysilicon-assisted SCRs can be improved to 3 times of conventional MLSCR＇s. Moreover, one-finger such polysilicon-assisted SCRs, which occupy only 947 [3mz layout area, can undergo 7-kV HBM ESD stress. Results further demonstrate that the S-type I-V characteristics of polysilicon-assisted SCRs are adjustable to different operating conditions by changing the device dimensions. Compared with traditional SCRs, this new SCR can bypass more ESD currents and consumes smaller IC area.展开更多
By using the pulsed laser single event effect facility and electro-static discharge （ESD） test system, the characteristics of the ＂high current＂, relation with external stimulus and relevance to impacted modes of ...By using the pulsed laser single event effect facility and electro-static discharge （ESD） test system, the characteristics of the ＂high current＂, relation with external stimulus and relevance to impacted modes of single event latch-up （SEL） and transient-induced latch-up （TLU） are studied, respectively, for a 12-bit complementary metal--oxide semiconductor （CMOS） analog-to-digital converter. Furthermore, the sameness and difference in physical mechanism between ＂high current＂ induced by SEL and that by TLU are disclosed in this paper. The results show that the minority carrier diffusion in the PNPN structure of the CMOS device which initiates the active parasitic NPN and PNP transistors is the common reason for the ＂high current＂ induced by SEL and for that by TLU, However, for SEL, the minority carder diffusion is induced by the ionizing radiation, and an underdamped sinusoidal voltage on the supply node （the ground node） is the cause of the minority carrier diffusion for TLU.展开更多
A new thyristor is proposed and realized in the foundry＇s 0.18-μm CMOS process for electrostatic dis-charge（ESD） protection.Without extra mask layers or process steps, the new ultra-low-voltage-trigger thyristor（...A new thyristor is proposed and realized in the foundry＇s 0.18-μm CMOS process for electrostatic dis-charge（ESD） protection.Without extra mask layers or process steps, the new ultra-low-voltage-trigger thyristor（ULVT thyristor） has a trigger voltage as low as 6.7 V and an ESD robustness exceeding 50 mA/μm, which enables effective ESD protection.Compared with the traditional medium-voltage-trigger thyristor（MVT thyristor）, the new structure not only has a lower trigger voltage, but can also provide better ESD protection under both positive and negative ESD zapping conditions.展开更多
To prevent the non-uniform conduction phenomenon caused by the Kirk effect in an NLDMOS under ESD stress, a novel NLDMOS structure is proposed. High electron injection current is the base of Kirk effect. Higher electr...To prevent the non-uniform conduction phenomenon caused by the Kirk effect in an NLDMOS under ESD stress, a novel NLDMOS structure is proposed. High electron injection current is the base of Kirk effect. Higher electron injection can makes the Kirk effect more serious and lead easily to the non-uniform conduction phenomenon. By splitting the drain N＋ with the field oxide in the proposed structure, the crowded current can lead to a higher voltage drop on the ballast resistance. Therefore, the non-uniform conduction is suppressed, and its failure current is much improved.展开更多
Aim of this work is to try to explain, on a Rational basis, some equations of Electro-Magnetism, which are based on Experimental data. Any Electric Field can produce a Field of many small Electric Dipoles, continuousl...Aim of this work is to try to explain, on a Rational basis, some equations of Electro-Magnetism, which are based on Experimental data. Any Electric Field can produce a Field of many small Electric Dipoles, continuously distributed in space. In a region, where the Electric Field is constant, in direction and magnitude, all the small Dipoles are parallel to the Electric Field, and are represented by a single, long, parallel to them, fixed in space, Electric Dipole, which is here called Compass. An Alternating current, in a straight Conductor, is studied, by a simple, short computer program, for step-by-step nonlinear dynamic analysis. It is found that, only an Alternating current, not a direct current, can produce an Electric Dipole, in a straight Conductor. The two above Dipoles (Compass-Conductor) are assumed with equal lengths ℓ, lying on two skew lines, perpendicular to each other, at a distance ℓ√2, thus forming, by their four ends, a Regular Tetrahedron, with side length ℓ. Repulsion, between Like Charges, obeys the simple Coulomb Electro-Static law. Whereas Interaction (Attraction or Repulsion), between Unlike Charges, obeys a more accurate Lennard-Jones law. The analysis of Dipole-Dipole (Compass-Conductor) Interaction is performed by hand calculator. The only out-of-balance forces, in the regular Tetrahedron, acting on the Rigid Conductor, are the so-called magnetic forces. Their direction is found, in a simple Rational way, with help of Regular Tetrahedron, without recoursing to a “right-hand-rule”. The proposed model is applied to 1) The force acting on an Electric Charge moving in a magnetic field. 2) The force acting on a Current carrying straight Conductor, due to a magnetic field. 3) The magnetic fields created around a Current carrying straight Conductor. In these applications, proposed model gives reasonable results. Particularly, in third application, results, obtained by proposed model, are found in satisfactory approximation with corresponding ones, obtained by an empiric展开更多
Electro-static discharge （ESD） is always a serious threat to integrated circuits. To achieve higher robustness and a smaller die area at the same time, a novel protection structure for the output pad is proposed. Th...Electro-static discharge （ESD） is always a serious threat to integrated circuits. To achieve higher robustness and a smaller die area at the same time, a novel protection structure for the output pad is proposed. The complementary SCR devices in this structure can protect not only the output under positive or negative stresses versus VDD or Vss, respectively, but also the power rails at the cost of almost no extra area. The robustness of the proposed structure is about three times higher than the conventional four-finger GGNMOS/GDPMOS structure in the same area condition.展开更多
A 4.1 GHz two-stage cascode Low-Noise Amplifier(LNA) with Electro-Static Discharge(ESD) protection is presented in this paper.The LNA has been optimized using ESD and LNA co-design methodology to achieve a good perfor...A 4.1 GHz two-stage cascode Low-Noise Amplifier(LNA) with Electro-Static Discharge(ESD) protection is presented in this paper.The LNA has been optimized using ESD and LNA co-design methodology to achieve a good performance.Post-layout simulation results exhibit a forward gain(S21) of about 21 dB, a reverse isolation(S12) of less than-18 dB, an input return loss(S11) of less than-16 dB, and an output return loss(S22) of less than-17 dB.Moreover, the Noise Figure(NF) is 2.6 dB.This design is implemented in TSMC0.18μm RF CMOS technology and the die area is 0.9 mm×0.9 mm.展开更多
基金This work was supported in part by the National Natural Science Foundation of China (Grant No. 29731020-1), the Beijing Natural Science Foundation (Grant No. 5992002),
文摘Analysis of electrostatic hydration free energies of the isomers of the 99mTc-BAT and 99mTc-DADT complexes is carried out using the computer simulation technique. The results show that not only a correlation exists between the logarithm of the brain uptake and the electrostatic hydration free energy for the isomers of 99mTc-brain radiopharmaceu-ticals, but also a linear relationship exists between the logarithm of the ratio of the brain uptake of the syn isomer to that of the anti one and the difference between the electrostatic hydration free energy of the syn-isomer and that of the anti one. Furthermore, the investigation on the important factors influencing the brain uptakes of 99mTc-radiophar-maceuticals and the reasons of the different biodistribution of the isomers of the 99mTc-complexes is explored at the molecular level. The results may provide a reference for the rational drug design of brain imaging agents.
文摘A novel polysilicon-assisted silicon-controlled rectifier （SCR） is presented and analyzed in this paper, which is fabricated in HHNEC＇s 0.18μm EEPROM process. The polysilicon-assisted SCRs take advantage of polysilicon layer to help bypass electro-static discharge （E S D） current without occupying extra layout area. TLP current-voltage （I-V） measurement results show that given the same layout areas, robustness performance of polysilicon-assisted SCRs can be improved to 3 times of conventional MLSCR＇s. Moreover, one-finger such polysilicon-assisted SCRs, which occupy only 947 [3mz layout area, can undergo 7-kV HBM ESD stress. Results further demonstrate that the S-type I-V characteristics of polysilicon-assisted SCRs are adjustable to different operating conditions by changing the device dimensions. Compared with traditional SCRs, this new SCR can bypass more ESD currents and consumes smaller IC area.
基金Project supported by the National Natural Science Foundation of China(Grant No.41304148)
文摘By using the pulsed laser single event effect facility and electro-static discharge （ESD） test system, the characteristics of the ＂high current＂, relation with external stimulus and relevance to impacted modes of single event latch-up （SEL） and transient-induced latch-up （TLU） are studied, respectively, for a 12-bit complementary metal--oxide semiconductor （CMOS） analog-to-digital converter. Furthermore, the sameness and difference in physical mechanism between ＂high current＂ induced by SEL and that by TLU are disclosed in this paper. The results show that the minority carrier diffusion in the PNPN structure of the CMOS device which initiates the active parasitic NPN and PNP transistors is the common reason for the ＂high current＂ induced by SEL and for that by TLU, However, for SEL, the minority carder diffusion is induced by the ionizing radiation, and an underdamped sinusoidal voltage on the supply node （the ground node） is the cause of the minority carrier diffusion for TLU.
文摘A new thyristor is proposed and realized in the foundry＇s 0.18-μm CMOS process for electrostatic dis-charge（ESD） protection.Without extra mask layers or process steps, the new ultra-low-voltage-trigger thyristor（ULVT thyristor） has a trigger voltage as low as 6.7 V and an ESD robustness exceeding 50 mA/μm, which enables effective ESD protection.Compared with the traditional medium-voltage-trigger thyristor（MVT thyristor）, the new structure not only has a lower trigger voltage, but can also provide better ESD protection under both positive and negative ESD zapping conditions.
基金Project supported by the Important National S&T Special Project of China(No.2010ZX02201-003-002)
文摘To prevent the non-uniform conduction phenomenon caused by the Kirk effect in an NLDMOS under ESD stress, a novel NLDMOS structure is proposed. High electron injection current is the base of Kirk effect. Higher electron injection can makes the Kirk effect more serious and lead easily to the non-uniform conduction phenomenon. By splitting the drain N＋ with the field oxide in the proposed structure, the crowded current can lead to a higher voltage drop on the ballast resistance. Therefore, the non-uniform conduction is suppressed, and its failure current is much improved.
文摘Aim of this work is to try to explain, on a Rational basis, some equations of Electro-Magnetism, which are based on Experimental data. Any Electric Field can produce a Field of many small Electric Dipoles, continuously distributed in space. In a region, where the Electric Field is constant, in direction and magnitude, all the small Dipoles are parallel to the Electric Field, and are represented by a single, long, parallel to them, fixed in space, Electric Dipole, which is here called Compass. An Alternating current, in a straight Conductor, is studied, by a simple, short computer program, for step-by-step nonlinear dynamic analysis. It is found that, only an Alternating current, not a direct current, can produce an Electric Dipole, in a straight Conductor. The two above Dipoles (Compass-Conductor) are assumed with equal lengths ℓ, lying on two skew lines, perpendicular to each other, at a distance ℓ√2, thus forming, by their four ends, a Regular Tetrahedron, with side length ℓ. Repulsion, between Like Charges, obeys the simple Coulomb Electro-Static law. Whereas Interaction (Attraction or Repulsion), between Unlike Charges, obeys a more accurate Lennard-Jones law. The analysis of Dipole-Dipole (Compass-Conductor) Interaction is performed by hand calculator. The only out-of-balance forces, in the regular Tetrahedron, acting on the Rigid Conductor, are the so-called magnetic forces. Their direction is found, in a simple Rational way, with help of Regular Tetrahedron, without recoursing to a “right-hand-rule”. The proposed model is applied to 1) The force acting on an Electric Charge moving in a magnetic field. 2) The force acting on a Current carrying straight Conductor, due to a magnetic field. 3) The magnetic fields created around a Current carrying straight Conductor. In these applications, proposed model gives reasonable results. Particularly, in third application, results, obtained by proposed model, are found in satisfactory approximation with corresponding ones, obtained by an empiric
基金supported by the National Natural Science Foundation of China(No.61274027)
文摘Electro-static discharge （ESD） is always a serious threat to integrated circuits. To achieve higher robustness and a smaller die area at the same time, a novel protection structure for the output pad is proposed. The complementary SCR devices in this structure can protect not only the output under positive or negative stresses versus VDD or Vss, respectively, but also the power rails at the cost of almost no extra area. The robustness of the proposed structure is about three times higher than the conventional four-finger GGNMOS/GDPMOS structure in the same area condition.
文摘A 4.1 GHz two-stage cascode Low-Noise Amplifier(LNA) with Electro-Static Discharge(ESD) protection is presented in this paper.The LNA has been optimized using ESD and LNA co-design methodology to achieve a good performance.Post-layout simulation results exhibit a forward gain(S21) of about 21 dB, a reverse isolation(S12) of less than-18 dB, an input return loss(S11) of less than-16 dB, and an output return loss(S22) of less than-17 dB.Moreover, the Noise Figure(NF) is 2.6 dB.This design is implemented in TSMC0.18μm RF CMOS technology and the die area is 0.9 mm×0.9 mm.
