Metal-insulator-metal (MIM) capacitors with atomic-layer-deposited Al2O3 dielectric and reactively sputtered TaN electrodes in application to radio frequency integrated circuits have been characterized electrically....Metal-insulator-metal (MIM) capacitors with atomic-layer-deposited Al2O3 dielectric and reactively sputtered TaN electrodes in application to radio frequency integrated circuits have been characterized electrically. The capacitors exhibit a high density of about 6.05 fF/μm^2, a small leakage current of 4.8 × 10^-8 A/cm^2 at 3 V, a high breakdown electric field of 8.61 MV/cm as well as acceptable voltage coefficients of capacitance (VCCs) of 795 ppm/V2 and 268ppm/V at 1 MHz. The observed properties should be attributed to high-quality Al2O3 film and chemically stable TaN electrodes. Further, a logarithmically linear relationship between quadratic VCC and frequency is observed due to the change of relaxation time with carrier mobility in the dielectric. The conduction mechanism in the high field ranges is dominated by the Poole-Frenkel emission, and the leakage current in the low field ranges is likely to be associated with trap-assisted tunnelling. Meanwhile, the Al2O3 dielectric presents charge trapping under low voltage stresses, and defect generation under high voltage stresses, and it has a hard-breakdown performance.展开更多
A model of monolithic transformers is presented, which is analyzed with characteristic functions. A closed- form analytical approach to extract all the model parameters for the equivalent circuit of Si-based on-chip t...A model of monolithic transformers is presented, which is analyzed with characteristic functions. A closed- form analytical approach to extract all the model parameters for the equivalent circuit of Si-based on-chip transformers is proposed. A novel de-coupling technique is first developed to reduce the complexity in the Y parameters for the transformer, and the model parameters can then be extracted analytically by a set of characteristic functions. Simulation based on the extracted parameters has been carried out for transformers with different structures, and good accuracy is obtained compared to a 3-demensional full-wave numerical electro- magnetic field solver. The presented approach will be very useful to provide a scalable and wide-band compact circuit model for Si-based RF transformers.展开更多
Millimeter-wave(mmWave)technology has been well studied for both outdoor long-distance transmission and indoor short-range communication.In the recently emerging fiber-to-the-room(FTTR)architecture in the home network...Millimeter-wave(mmWave)technology has been well studied for both outdoor long-distance transmission and indoor short-range communication.In the recently emerging fiber-to-the-room(FTTR)architecture in the home network of the fifth generation fixed networks(F5G),mmWave technology can be cascaded well to a new optical network terminal in the room to enable extremely high data rate communication(i.e.,>10 Gb/s).In the FTTR+mmWave scenario,the rapid degradation of the mmWave signal in long-distance transmission and the significant loss against wall penetration are no longer the bottlenecks for real application.Moreover,the surrounding walls of every room provide excellent isolation to avoid interference and guarantee security.This paper provides insights and analysis for the new FTTR+mmWave architecture to improve the customer experience in future broadband services such as immersive audiovisual videos.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No 90607023), Shanghai Pujiang Program (Grant No 05PJ14017), SRF for R0CS, SEM, and the Micro/Nano-electronics Science and Technology Innovation Platform (985) and the Ministry of Education of China in the International Research Training Group "Materials and Concepts for Advanced Interconnects
文摘Metal-insulator-metal (MIM) capacitors with atomic-layer-deposited Al2O3 dielectric and reactively sputtered TaN electrodes in application to radio frequency integrated circuits have been characterized electrically. The capacitors exhibit a high density of about 6.05 fF/μm^2, a small leakage current of 4.8 × 10^-8 A/cm^2 at 3 V, a high breakdown electric field of 8.61 MV/cm as well as acceptable voltage coefficients of capacitance (VCCs) of 795 ppm/V2 and 268ppm/V at 1 MHz. The observed properties should be attributed to high-quality Al2O3 film and chemically stable TaN electrodes. Further, a logarithmically linear relationship between quadratic VCC and frequency is observed due to the change of relaxation time with carrier mobility in the dielectric. The conduction mechanism in the high field ranges is dominated by the Poole-Frenkel emission, and the leakage current in the low field ranges is likely to be associated with trap-assisted tunnelling. Meanwhile, the Al2O3 dielectric presents charge trapping under low voltage stresses, and defect generation under high voltage stresses, and it has a hard-breakdown performance.
文摘A model of monolithic transformers is presented, which is analyzed with characteristic functions. A closed- form analytical approach to extract all the model parameters for the equivalent circuit of Si-based on-chip transformers is proposed. A novel de-coupling technique is first developed to reduce the complexity in the Y parameters for the transformer, and the model parameters can then be extracted analytically by a set of characteristic functions. Simulation based on the extracted parameters has been carried out for transformers with different structures, and good accuracy is obtained compared to a 3-demensional full-wave numerical electro- magnetic field solver. The presented approach will be very useful to provide a scalable and wide-band compact circuit model for Si-based RF transformers.
文摘Millimeter-wave(mmWave)technology has been well studied for both outdoor long-distance transmission and indoor short-range communication.In the recently emerging fiber-to-the-room(FTTR)architecture in the home network of the fifth generation fixed networks(F5G),mmWave technology can be cascaded well to a new optical network terminal in the room to enable extremely high data rate communication(i.e.,>10 Gb/s).In the FTTR+mmWave scenario,the rapid degradation of the mmWave signal in long-distance transmission and the significant loss against wall penetration are no longer the bottlenecks for real application.Moreover,the surrounding walls of every room provide excellent isolation to avoid interference and guarantee security.This paper provides insights and analysis for the new FTTR+mmWave architecture to improve the customer experience in future broadband services such as immersive audiovisual videos.