A novel double-layer film of SiCOF/a-C ： F with a low dielectric constant is deposited using a PECVD system. The chemical structure of the film is characterized with Fourier transform infrared spectroscopy （FTIR）. ...A novel double-layer film of SiCOF/a-C ： F with a low dielectric constant is deposited using a PECVD system. The chemical structure of the film is characterized with Fourier transform infrared spectroscopy （FTIR）. The measurements of the film refractive index reveal that the optical frequency dielectric constant （n^2） of the film is almost constant as a function of air exposure time, however, with increasing annealing temperature, the value of n^2 for the film decreases. Possible mechanisms are discussed in detail. The analysis of SIMS profiles for the metal-insulator-silicon structures reveal that in the Al/a-C ： F/Si structure,the annealing causes a more rapid diffusion of F in AI in comparison with C, but there is no obvious difference in Si. In addition, no recognizable verge exists between SiCOF and a-C ： F films,and the SiCOF film acts as a barrier against the diffusion of carbon into the aluminum layer.展开更多
Low-dielectric-constant poly(acetoxystyrenezhi-co-octavinyl-polyhedral oligomeric silsesquioxane)(PAS-POSS) organicinorganic hybrid nanocomposite was successfully synthesized via one-step free radical polymerization a...Low-dielectric-constant poly(acetoxystyrenezhi-co-octavinyl-polyhedral oligomeric silsesquioxane)(PAS-POSS) organicinorganic hybrid nanocomposite was successfully synthesized via one-step free radical polymerization and characterized by FTIR,high-resolution ~1H NMR,^(29)Si NMR,DSC,TGA,AFM,spectroscopic elhpsometry and dielectric constants measurements. The results show T_g and T_(dec) were elevated dramatically due to the incorporation of inorganic POSS cores.Spectroscopic ellipsometry and dielectric consta...展开更多
A novel partial silicon-on-insulator （PSOI） high voltage device with a low-k （relative permittivity） dielectric buried layer （LK PSOI） and its breakdown mechanism are presented and investigated by MEDICI. At a l...A novel partial silicon-on-insulator （PSOI） high voltage device with a low-k （relative permittivity） dielectric buried layer （LK PSOI） and its breakdown mechanism are presented and investigated by MEDICI. At a low k value the electric field strength in the dielectric buried layer （EI） is enhanced and a Si window makes the substrate share the vertical drop, resulting in a high vertical breakdown voltage; in the lateral direction, a high electric field peak is introduced at the Si window, which modulates the electric field distribution in the SOI layer; consequently, a high breakdown voltage （BV） is obtained. The values of EI and BV of LK PSOI with ki = 2 on a 2μm thick SOI layer over 1μm thick buried layer are enhanced by 74% and 19%, respectively, compared with those of the conventional PSOI. Furthermore, the Si window also alleviates the self-heating effect.展开更多
This paper investigates the capacitance-voltage （C-V） characteristics of F doping SiCOH low dielectric constant films metal-insulator-semiconductor structure. The F doping SiCOH films are deposited by decamethylcycl...This paper investigates the capacitance-voltage （C-V） characteristics of F doping SiCOH low dielectric constant films metal-insulator-semiconductor structure. The F doping SiCOH films are deposited by decamethylcyclopentasilox-ane [DMCPS） and trifluromethane （CHF3） electron cyclotron resonance plasmas. With the CHF3/DMCPS flow rate ratio from 0 to 0.52, the positive excursion of C-V curves and the increase of fiat-band voltage VFB from -6.1 V to 32.2V are obtained. The excursion of C-V curves and the shift of VFB are related to the change of defects density and type at the Si/SiCOH interface due to the decrease of Si and O concentrations, and the increase of F concentration. At the CHF3/DMCPS flow rate ratio is 0.12, the compensation of F-bonding dangling bond to Si dangling bond leads to a small VFB of 2.0V.展开更多
We report an improved method for the preparation of highly dense nickelate ceramics at relatively low temperature. It is found that the introduction of appropriate additives during the ball-milling process facilitates...We report an improved method for the preparation of highly dense nickelate ceramics at relatively low temperature. It is found that the introduction of appropriate additives during the ball-milling process facilitates the formation of nickelate phase through solid state reaction. Moreover, although high-purity nickelate powders can only be obtained by calcining the mixture of starting materials at temperature higher than 1100 ℃. The adoption of powders calcined at 1000 ℃, rather than those calcined at higher temperature, is conductive to the low-temperature densification of nickelate ceramics, which is attributed to the small and dispersive particles, and the solid state reaction of the residual starting materials during sintering. Compared with the conventional process, the improved method can reduce the sintering temperature of nickelate ceramics by about 100 ℃ and decrease the grain size of the obtained ceramics, and therefore makes nickelate meet the fabrication requirements of multi-layer ceramic capacitors（MLCC）.展开更多
With the advent of the 5 G era,advanced packaging applications such as wafer-level fan-out packaging have emerged thanks to efforts to reduce signal loss and increase signal transmission rates.As one of the key materi...With the advent of the 5 G era,advanced packaging applications such as wafer-level fan-out packaging have emerged thanks to efforts to reduce signal loss and increase signal transmission rates.As one of the key materials employed in telecommunication devices,the interlayer dielectric material directly affects signal transmission and device reliability.Among them,polyimide(PI)has become an important interlayer dielectric material because of its excellent comprehensive properties.However,in order to meet the needs high-frequency and high-speed circuits for 5 G networks,it will be necessary to further reduce the dielectric constant and dielectric loss of PI.PI is widely used as a flexible dielectric material due to its excellent electrical insulation properties(dielectric constant≈3.0-4.0,dielectric loss≈0.02),mechanical properties,and thermal resistance.However,further reduction in the dielectric constant will be needed in order for PI-based materials to better meet the current high integration development needs of the microelectronics industry.This article starts from strategies to prepare low dielectric PI that have been developed in the last decade,based on a more systematic and inductive analysis,and prospects the development potential of low dielectric PI.展开更多
PVA （Polyvinyl Alcohol） is a water soluble organic dielectric, easily solution processed to fabricate films by spin coating, dip coating or inkjet printing. It has been used as a dielectric layer in OTFTs （organic ...PVA （Polyvinyl Alcohol） is a water soluble organic dielectric, easily solution processed to fabricate films by spin coating, dip coating or inkjet printing. It has been used as a dielectric layer in OTFTs （organic thin film transistors）, and its dielectric constant is around 3.5-10. For OTFTs operating at lower voltage, it is desirable to increase the dielectric constant. Here, we report a technique to incorporate upto 50 wt% of TiO2 nanoparticles （15-25 nm） in PVA to increase its dielectric constant. Rutile phase of TiO2 is used, because of its higher dielectric constant （e = 114） compared to anatase phase （E = 31）. We have made inks containing 10 and 50 wt% （of PVA） TiO2 nanoparticles, which is stable upto six months. PVA-TiO2 dispersions and PVA （without TiO2） were spin coated on indium tin oxide coated polyethylene terephthalate substrate. Film structure was studied using SEM （scanning electron microscopy）. Absorption study of the films confirms presence of TiO2 nanoparticles. M-I-M capacitors were fabricated by thermally evaporating aluminium on top of the dielectric films. We observed enhancement in dielectric constant by a factor of 2 for PVA containing 50 wt% TiO2 in comparison to PVA＇s dielectric constant. There is no concomitant increase in the leakage current.展开更多
文摘A novel double-layer film of SiCOF/a-C ： F with a low dielectric constant is deposited using a PECVD system. The chemical structure of the film is characterized with Fourier transform infrared spectroscopy （FTIR）. The measurements of the film refractive index reveal that the optical frequency dielectric constant （n^2） of the film is almost constant as a function of air exposure time, however, with increasing annealing temperature, the value of n^2 for the film decreases. Possible mechanisms are discussed in detail. The analysis of SIMS profiles for the metal-insulator-silicon structures reveal that in the Al/a-C ： F/Si structure,the annealing causes a more rapid diffusion of F in AI in comparison with C, but there is no obvious difference in Si. In addition, no recognizable verge exists between SiCOF and a-C ： F films,and the SiCOF film acts as a barrier against the diffusion of carbon into the aluminum layer.
基金financially supported by the National Natural Science Foundation of China(Nos.90606011, 50472038 and 2097401)PhD Program Foundation of Ministry of Education of China(No.20070255012)+3 种基金Shanghai Leading Academic Discipline Project(No.B603)Open Project of The State Key Laboratory of Crystal Materials(KF0809)the Program of Introducing Talents of Discipline to Universities(No.111-2-04)Doctoral Dissertation Innovation Project(No.BC200907)
文摘Low-dielectric-constant poly(acetoxystyrenezhi-co-octavinyl-polyhedral oligomeric silsesquioxane)(PAS-POSS) organicinorganic hybrid nanocomposite was successfully synthesized via one-step free radical polymerization and characterized by FTIR,high-resolution ~1H NMR,^(29)Si NMR,DSC,TGA,AFM,spectroscopic elhpsometry and dielectric constants measurements. The results show T_g and T_(dec) were elevated dramatically due to the incorporation of inorganic POSS cores.Spectroscopic ellipsometry and dielectric consta...
基金supported by the National Natural Science Foundation of China (Grant Nos. 60806025 and 60976060)the National Laboratory of Analog Integrated Circuit (Grant No. 9140C0903070904)the Youth Teacher Foundation of the University of Electronic Science and Technology of China (Grant No. jx0721)
文摘A novel partial silicon-on-insulator （PSOI） high voltage device with a low-k （relative permittivity） dielectric buried layer （LK PSOI） and its breakdown mechanism are presented and investigated by MEDICI. At a low k value the electric field strength in the dielectric buried layer （EI） is enhanced and a Si window makes the substrate share the vertical drop, resulting in a high vertical breakdown voltage; in the lateral direction, a high electric field peak is introduced at the Si window, which modulates the electric field distribution in the SOI layer; consequently, a high breakdown voltage （BV） is obtained. The values of EI and BV of LK PSOI with ki = 2 on a 2μm thick SOI layer over 1μm thick buried layer are enhanced by 74% and 19%, respectively, compared with those of the conventional PSOI. Furthermore, the Si window also alleviates the self-heating effect.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10575074)
文摘This paper investigates the capacitance-voltage （C-V） characteristics of F doping SiCOH low dielectric constant films metal-insulator-semiconductor structure. The F doping SiCOH films are deposited by decamethylcyclopentasilox-ane [DMCPS） and trifluromethane （CHF3） electron cyclotron resonance plasmas. With the CHF3/DMCPS flow rate ratio from 0 to 0.52, the positive excursion of C-V curves and the increase of fiat-band voltage VFB from -6.1 V to 32.2V are obtained. The excursion of C-V curves and the shift of VFB are related to the change of defects density and type at the Si/SiCOH interface due to the decrease of Si and O concentrations, and the increase of F concentration. At the CHF3/DMCPS flow rate ratio is 0.12, the compensation of F-bonding dangling bond to Si dangling bond leads to a small VFB of 2.0V.
基金supported by the Natural Science Foundation of Fujian Province(2015j01231)the Chunmiao Project of Haixi Institute of Chinese Academy of Sciences(CMZX-2014-005)the National Key Research and Development Program of China(2016YFB0701003)
文摘We report an improved method for the preparation of highly dense nickelate ceramics at relatively low temperature. It is found that the introduction of appropriate additives during the ball-milling process facilitates the formation of nickelate phase through solid state reaction. Moreover, although high-purity nickelate powders can only be obtained by calcining the mixture of starting materials at temperature higher than 1100 ℃. The adoption of powders calcined at 1000 ℃, rather than those calcined at higher temperature, is conductive to the low-temperature densification of nickelate ceramics, which is attributed to the small and dispersive particles, and the solid state reaction of the residual starting materials during sintering. Compared with the conventional process, the improved method can reduce the sintering temperature of nickelate ceramics by about 100 ℃ and decrease the grain size of the obtained ceramics, and therefore makes nickelate meet the fabrication requirements of multi-layer ceramic capacitors（MLCC）.
基金supported by Department of Education of Liaoning Province(LQ2019004 and LZ2019005).
文摘With the advent of the 5 G era,advanced packaging applications such as wafer-level fan-out packaging have emerged thanks to efforts to reduce signal loss and increase signal transmission rates.As one of the key materials employed in telecommunication devices,the interlayer dielectric material directly affects signal transmission and device reliability.Among them,polyimide(PI)has become an important interlayer dielectric material because of its excellent comprehensive properties.However,in order to meet the needs high-frequency and high-speed circuits for 5 G networks,it will be necessary to further reduce the dielectric constant and dielectric loss of PI.PI is widely used as a flexible dielectric material due to its excellent electrical insulation properties(dielectric constant≈3.0-4.0,dielectric loss≈0.02),mechanical properties,and thermal resistance.However,further reduction in the dielectric constant will be needed in order for PI-based materials to better meet the current high integration development needs of the microelectronics industry.This article starts from strategies to prepare low dielectric PI that have been developed in the last decade,based on a more systematic and inductive analysis,and prospects the development potential of low dielectric PI.
文摘PVA （Polyvinyl Alcohol） is a water soluble organic dielectric, easily solution processed to fabricate films by spin coating, dip coating or inkjet printing. It has been used as a dielectric layer in OTFTs （organic thin film transistors）, and its dielectric constant is around 3.5-10. For OTFTs operating at lower voltage, it is desirable to increase the dielectric constant. Here, we report a technique to incorporate upto 50 wt% of TiO2 nanoparticles （15-25 nm） in PVA to increase its dielectric constant. Rutile phase of TiO2 is used, because of its higher dielectric constant （e = 114） compared to anatase phase （E = 31）. We have made inks containing 10 and 50 wt% （of PVA） TiO2 nanoparticles, which is stable upto six months. PVA-TiO2 dispersions and PVA （without TiO2） were spin coated on indium tin oxide coated polyethylene terephthalate substrate. Film structure was studied using SEM （scanning electron microscopy）. Absorption study of the films confirms presence of TiO2 nanoparticles. M-I-M capacitors were fabricated by thermally evaporating aluminium on top of the dielectric films. We observed enhancement in dielectric constant by a factor of 2 for PVA containing 50 wt% TiO2 in comparison to PVA＇s dielectric constant. There is no concomitant increase in the leakage current.
