The preparation of lead-free thick-film resistors are reported:using RuO 2 and ruthenates as conductive particles,glass powders composed of B 2 O 3,SiO 2,CaO and Al2 O 3 as insulating phase,adding organic matter which...The preparation of lead-free thick-film resistors are reported:using RuO 2 and ruthenates as conductive particles,glass powders composed of B 2 O 3,SiO 2,CaO and Al2 O 3 as insulating phase,adding organic matter which mainly consists of ethyl cellulose and terpineol to form printable pastes.Resistors were fabricated and sintered by conventional screen-printing on 96%Al 2 O 3 substrates,and then sintering in a belt furnace.X-ray diffraction(XRD) and electron scanning microscopy(SEM) have been used to characterize the conductive particles.The resistors exhibit good refiring stability and low temperature coefficient of resistance.Sheet resistance spans from about 80Ω/□ to 600Ω/□.The resistors prepared are qualified for common use.展开更多
The traditional hermetic packaging methods,which require high temperatures and high voltages,would have adverse effects on electronics devices.Based on current-assisted sintering technology,we proposed a new hermetic ...The traditional hermetic packaging methods,which require high temperatures and high voltages,would have adverse effects on electronics devices.Based on current-assisted sintering technology,we proposed a new hermetic packaging method using silver paste.Comparing the microstructure of the joints sintered with different currents,we found that with the increasing sintering current from 4.7 kA to 5.3 kA,the density of the joint increases,which improves the hermeticity and bonding strength of the joints.The results of thermal cycling tests showed that the sealing joints sintered at 4.7 kA with larger porosity are more prone to fail because pores tend to be sources of defects under thermal cycling.After 250 ℃ high thermal storage,there is the coarsening of the pores and the delamination near the Ag/Au interface,degrading the sealing performance of the sintered joint.Besides,the sealing joints sintered at 5.3 kA exhibit superior reliability when exposed to high temperatures.展开更多
The poly(epoxy-N-methylaniline)conductive organic carrier was used as the bonding phase of the low-temperature conductive silver paste.Then,this was mixed with different proportions of silver powder to prepare the low...The poly(epoxy-N-methylaniline)conductive organic carrier was used as the bonding phase of the low-temperature conductive silver paste.Then,this was mixed with different proportions of silver powder to prepare the low-temperature conductive silver paste.Afterwards,the effect of the conductive organic carrier on the properties of the low-temperature conductive silver paste was determined by IR,DMA and SEM.The results revealed that the prepared conductive paste has good conductivity,film-forming performance,printing performance,low-temperature curing performance,and anti-aging performance.When the mass percentage of the bonding phase/conductive phase was 40/60,the lowest volume resistivity of the conductive silver paste was 4.9×10^(−6)Ω⋅cm,and the conductivity was the best.展开更多
Strain sensors for human-motion detection must offer high stretchability, high sensitivity, fast response, and high recovery speed. In this study, we choose silver paste as a sensing material and use a screen printing...Strain sensors for human-motion detection must offer high stretchability, high sensitivity, fast response, and high recovery speed. In this study, we choose silver paste as a sensing material and use a screen printing method to fabricate the strain sensor based upon an electrical-resistance mechanism. After curing elastomeric polyurethane film with a thickness of 150 μm on PET film, the polyester resin mixed with blocked isocyanate curing agent was coated as a masking layer to reduce the film’s stickiness. The effect of the polyester masking layer upon the silver paste screen printing process was examined using a rolling-ball-tack test, TGA analysis of polyester resins, and cured silver-electrode films. The cost-effective strain sensor fabricated by using silver paste and screen printing processes on the stretchable-polyurethane-substrate film showed high sensitivity and fast response in a strain range of up to 100%.展开更多
In the present study,we investigate several textile coating pastes used in the market based on their radiation protection capability for gamma rays.The gamma ray mass absorption coefficients of some coating pastes dop...In the present study,we investigate several textile coating pastes used in the market based on their radiation protection capability for gamma rays.The gamma ray mass absorption coefficients of some coating pastes doped with antimony,boron and silver elements have been investigated.It has been determined that the gamma ray mass attenuation coefficient decreases rapidly as the energy of the gamma rays increases.It was determined that the doping of the main printing paste with silver and antimony considerably increased the gamma ray absorption capability of main paste.However,the doping of the paste with boron reduces the mass absorption of gamma rays.In particular,the gamma ray mass absorption power of the main paste doped with silver and antimony was determined to be useful in the gamma energy range from 80 to 140keV.This indicates that the newly doped textile material may be considered for radiation protection in the case of low-energy gamma rays.展开更多
文摘The preparation of lead-free thick-film resistors are reported:using RuO 2 and ruthenates as conductive particles,glass powders composed of B 2 O 3,SiO 2,CaO and Al2 O 3 as insulating phase,adding organic matter which mainly consists of ethyl cellulose and terpineol to form printable pastes.Resistors were fabricated and sintered by conventional screen-printing on 96%Al 2 O 3 substrates,and then sintering in a belt furnace.X-ray diffraction(XRD) and electron scanning microscopy(SEM) have been used to characterize the conductive particles.The resistors exhibit good refiring stability and low temperature coefficient of resistance.Sheet resistance spans from about 80Ω/□ to 600Ω/□.The resistors prepared are qualified for common use.
基金supported by the National High Technology Research and Development Program of China (No.2016YFB0100602)。
文摘The traditional hermetic packaging methods,which require high temperatures and high voltages,would have adverse effects on electronics devices.Based on current-assisted sintering technology,we proposed a new hermetic packaging method using silver paste.Comparing the microstructure of the joints sintered with different currents,we found that with the increasing sintering current from 4.7 kA to 5.3 kA,the density of the joint increases,which improves the hermeticity and bonding strength of the joints.The results of thermal cycling tests showed that the sealing joints sintered at 4.7 kA with larger porosity are more prone to fail because pores tend to be sources of defects under thermal cycling.After 250 ℃ high thermal storage,there is the coarsening of the pores and the delamination near the Ag/Au interface,degrading the sealing performance of the sintered joint.Besides,the sealing joints sintered at 5.3 kA exhibit superior reliability when exposed to high temperatures.
基金fund for this work was provided by the“Research on Key Technologies of Photosensitive Conductive Silver Paste Based on Domestic Circuit Protection Micro Chip Components”(Project No.BE2020008 and Supporting Author:Chen P).
文摘The poly(epoxy-N-methylaniline)conductive organic carrier was used as the bonding phase of the low-temperature conductive silver paste.Then,this was mixed with different proportions of silver powder to prepare the low-temperature conductive silver paste.Afterwards,the effect of the conductive organic carrier on the properties of the low-temperature conductive silver paste was determined by IR,DMA and SEM.The results revealed that the prepared conductive paste has good conductivity,film-forming performance,printing performance,low-temperature curing performance,and anti-aging performance.When the mass percentage of the bonding phase/conductive phase was 40/60,the lowest volume resistivity of the conductive silver paste was 4.9×10^(−6)Ω⋅cm,and the conductivity was the best.
文摘Strain sensors for human-motion detection must offer high stretchability, high sensitivity, fast response, and high recovery speed. In this study, we choose silver paste as a sensing material and use a screen printing method to fabricate the strain sensor based upon an electrical-resistance mechanism. After curing elastomeric polyurethane film with a thickness of 150 μm on PET film, the polyester resin mixed with blocked isocyanate curing agent was coated as a masking layer to reduce the film’s stickiness. The effect of the polyester masking layer upon the silver paste screen printing process was examined using a rolling-ball-tack test, TGA analysis of polyester resins, and cured silver-electrode films. The cost-effective strain sensor fabricated by using silver paste and screen printing processes on the stretchable-polyurethane-substrate film showed high sensitivity and fast response in a strain range of up to 100%.
基金supported by the Sinop University Scientific Research Projects Coordinator(No.GMYO-1901-16-14)。
文摘In the present study,we investigate several textile coating pastes used in the market based on their radiation protection capability for gamma rays.The gamma ray mass absorption coefficients of some coating pastes doped with antimony,boron and silver elements have been investigated.It has been determined that the gamma ray mass attenuation coefficient decreases rapidly as the energy of the gamma rays increases.It was determined that the doping of the main printing paste with silver and antimony considerably increased the gamma ray absorption capability of main paste.However,the doping of the paste with boron reduces the mass absorption of gamma rays.In particular,the gamma ray mass absorption power of the main paste doped with silver and antimony was determined to be useful in the gamma energy range from 80 to 140keV.This indicates that the newly doped textile material may be considered for radiation protection in the case of low-energy gamma rays.
