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
The emission of electrons from the surface of a solid caused by a high electric field is called field emission (FE). Electron sources based on FE are used today in a wide range of applications, such as microwave tra...The emission of electrons from the surface of a solid caused by a high electric field is called field emission (FE). Electron sources based on FE are used today in a wide range of applications, such as microwave traveling wave tubes, e-beam evaporators, mass spectrometers, flat panel of field emission displays (FEDs), and highly efficient lamps. Since the discovery of carbon nanombes (CNTs) in 1991, much attention has been paid to explore the usage of these ideal one-dimensional (ID) nanomater- ials as field emitters achieving high FE current density at a low electric field because of their high aspect ratio and "whisker-like" shape for optimum geometrical field enhancement. 1D metal oxide semiconductors, such as ZnO and WO3 possess high melting point and chemical stability, thereby allowing a higher oxygen partial pressure and poorer vacuum in FE applications. In addition, unlike CNTs, in which both semiconductor and metallic CNTs can co-exist in the as-synthesized products, it is possible to prepare 1D semiconductor nanostructures with a unique electronic property. Moreover, I D semiconductor nanos- tructures generally have the advantage of a lower surface potential barrier than that of CNTs due to lower electron affinity and the conductivity could be enhanced by doping with certain elements. As a consequence, there has been increasing interest in the investigation of 1D metal oxide nanostructure as an appropriate alternative FE electron source to CNT for FE devices in the past few years. This paper provides a comprehensive review of the state-of-the- art research activities in the field. It mainly focuses on FE properties and applications of the most widely studied 1D ZnO nanostructures, such as nanowires (NWs), nanobelts, nanoneedles and nanotubes (NTs). We begin with the growth mechanism, and then systematically discuss the recent progresses on several kinds of important nano- structures and their FE characteristics and applications in details. Finally, it is concluded with the outlook and future research tendency in the area.展开更多
Transmission lines (T-Lines) are widely used in millimeter wave applications on silicon-based complementary metal-oxide semiconductor (CMOS) technology. Accurate modeling of T-lines to capture the related electric...Transmission lines (T-Lines) are widely used in millimeter wave applications on silicon-based complementary metal-oxide semiconductor (CMOS) technology. Accurate modeling of T-lines to capture the related electrical effects has, therefore, become increasingly important. This paper describes a method to model the capacitance and conductance of T-Lines on CMOS multilayer, Iossy substrates based on conformal mapping, and region subdivision. Tests show that the line parameters (per unit length) obtained by the method are frequency dependent and very accurate. The method is also suitable for parallel multiconductor interconnect modeling for high frequency circuits.展开更多
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.
文摘The emission of electrons from the surface of a solid caused by a high electric field is called field emission (FE). Electron sources based on FE are used today in a wide range of applications, such as microwave traveling wave tubes, e-beam evaporators, mass spectrometers, flat panel of field emission displays (FEDs), and highly efficient lamps. Since the discovery of carbon nanombes (CNTs) in 1991, much attention has been paid to explore the usage of these ideal one-dimensional (ID) nanomater- ials as field emitters achieving high FE current density at a low electric field because of their high aspect ratio and "whisker-like" shape for optimum geometrical field enhancement. 1D metal oxide semiconductors, such as ZnO and WO3 possess high melting point and chemical stability, thereby allowing a higher oxygen partial pressure and poorer vacuum in FE applications. In addition, unlike CNTs, in which both semiconductor and metallic CNTs can co-exist in the as-synthesized products, it is possible to prepare 1D semiconductor nanostructures with a unique electronic property. Moreover, I D semiconductor nanos- tructures generally have the advantage of a lower surface potential barrier than that of CNTs due to lower electron affinity and the conductivity could be enhanced by doping with certain elements. As a consequence, there has been increasing interest in the investigation of 1D metal oxide nanostructure as an appropriate alternative FE electron source to CNT for FE devices in the past few years. This paper provides a comprehensive review of the state-of-the- art research activities in the field. It mainly focuses on FE properties and applications of the most widely studied 1D ZnO nanostructures, such as nanowires (NWs), nanobelts, nanoneedles and nanotubes (NTs). We begin with the growth mechanism, and then systematically discuss the recent progresses on several kinds of important nano- structures and their FE characteristics and applications in details. Finally, it is concluded with the outlook and future research tendency in the area.
基金Supported by the National Natural Science Foundation of China (No. 90307016) the Basic Research Foundation of Tsinghua National Laboratory for Information Science and Technology (TNList)
文摘Transmission lines (T-Lines) are widely used in millimeter wave applications on silicon-based complementary metal-oxide semiconductor (CMOS) technology. Accurate modeling of T-lines to capture the related electrical effects has, therefore, become increasingly important. This paper describes a method to model the capacitance and conductance of T-Lines on CMOS multilayer, Iossy substrates based on conformal mapping, and region subdivision. Tests show that the line parameters (per unit length) obtained by the method are frequency dependent and very accurate. The method is also suitable for parallel multiconductor interconnect modeling for high frequency circuits.