嵌入电容膜（ECF）用的环氧／SrTiO3复合物

概述了高频用途的环氧／SrTiO3复合物嵌入电容膜（ECF）的开发。采用变化SrTiO3粒子填料的3种不同的SrTiO3粉,测量环氧／SrTiO3复合物嵌入电容膜的介质常数。试验数据符合判断环氧／SrTiO3复合物ECF中的SrTiO3粉的有效介质常数的Lichtenecker方程。应用矩形谐振腔法测量环氧／SrTiO3复合物ECF在千兆赫范围（1GHz、10GHz）的介质常数。在千兆赫频率范围内环氧／SrTiO3复合物ECF的介质常数几乎稳定。因此环氧／SrTiO3复合物ECF可以有效地应用于高频用途中。     

A study on the temperature dependence of epoxy/BaTiO<Subscript>3</Subscript> composite embedded capacitor films

In this study, the temperature dependence of capacitance, one of the most important properties of embedded capacitor films (ECFs), was investigated. The temperature dependence of the capacitance of ECFs was determined by the temperature dependence of the dielectric constant and thickness, and among these, the main factor was the dielectric constant of ECFs. The dielectric constant of ECFs was determined by that of epoxy and BaTiO₃ powders. Below 130°C, the dielectric constant of ECFs increased as temperature increased, and was mainly affected by an epoxy matrix. However, above 130°C (the Curie temperature of BaTiO₃), the increased rate of the dielectric constant of ECFs started decreasing. This was due to the fact that BaTiO₃ powder undergoes a phase transition from a tetragonal to a cubic structure, and its dielectric constant decreases at 130°C. The dielectric constant of BaTiO₃ powder was obtained from measured dielectric constants of ECF and application of the Lichtenecker logarithmic rule.     

一种内埋式电容器用钛酸钡/环氧复合材料的研制

基于钛酸钡和丁腈橡胶的高介电常数特性,研制了一种可用于内埋式电容器的钛酸钡/环氧复合材料.以丁腈橡胶作为添加剂,用共混法制备钛酸钡/环氧复合材料,探讨了钛酸钡和丁腈橡胶含量对复合材料介电常数、介电损耗因子、体积电阻率及击穿电压等介电性能的影响.实验结果表明,丁腈橡胶可以提高钛酸钡/环氧复合材料的介电常数.在钛酸钡体积分数为40%时,通过添加15%的丁腈橡胶,复合材料的介电常数可从25提高到41,体积电阻率达1011Ω·m,击穿电压达8 kV/mm,而介电损耗因子仍小于0.02.为工业化低成本生产内埋式电容器材料提供了一种新的方法.     

环氧/BaTiO3复合物埋入电容膜和电容膏

概述了环氧/BaTiO3复合物埋入电容膜和电容膏的开发,它们适用于PCB之类的有机基材内制造具有高介质常数和低误差的埋入电容.     

Integrated high-/spl kappa/ (/spl kappa/ /spl sim/19) MIM capacitor with Cu/low-/spl kappa/ interconnects for RF application

We demonstrate a high-performance metal-high /spl kappa/ insulator-metal (MIM) capacitor integrated with a Cu/low-/spl kappa/ backend interconnection. The high-/spl kappa/ used was laminated HfO/sub 2/-Al/sub 2/O/sub 3/ with effective /spl kappa/ /spl sim/19 and the low-/spl kappa/ dielectric used was Black Diamond with /spl kappa/ /spl sim/2.9. The MIM capacitor (/spl sim/13.4 fF//spl mu/m/sup 2/) achieved a Q-factor /spl sim/53 at 2.5 GHz and 11.7 pF. The resonant frequency f/sub r/ was 21% higher in comparison to an equivalently integrated Si/sub 3/N/sub 4/-MIM capacitor (/spl sim/0.93 fF//spl mu/m/sup 2/) having similar capacitance 11.2 pF. The impacts of high-/spl kappa/ insulator and low-/spl kappa/ interconnect dielectric on the mechanism for resonant frequency improvement are distinguished using equivalent circuit analysis. This letter suggests that integrated high-/spl kappa/ MIM could be a promising alternative capacitor structure for future high-performance RF applications.     

Reduced Temperature Coefficient of Capacitance (TCC) of Embedded Capacitor Films (ECFs) for Organic Substrates using SrTiO3 and Multifunctional Epoxy

Epoxy/ceramic composites have attracted great interest as embedded capacitor materials, mainly due to the process compatibility of epoxy with printed circuit boards (PCBs). However, one of the potential problems of epoxy/ceramic composites is the temperature dependence of their dielectric properties. This study focuses mainly on reducing the temperature coefficient of capacitance (TCC) of epoxy/ceramic composites using multifunctional epoxy and SrTiO₃ powder. The TCC of an epoxy/ceramic composite mainly depends on the properties of its epoxy and ceramic powder. Using multifunctional epoxy, the epoxy resin showed two glass-transition temperatures, resulting in a lower dimensional change after the first glass-transition temperature. Additionally, the TCC of epoxy/SrTiO₃ ECFs can be decreased by increasing the SrTiO₃ powder content. As a result, reduced TCC of epoxy/ceramic composite capacitors using a multifunctional epoxy and SrTiO₃ powder was successfully demonstrated for embedded capacitors in organic substrates.     

Electrical characteristics and lifetimes of microdischarge devices having thin dielectric films of aluminum oxide,boron nitride, or barium titanate

The electrical (V-I) characteristics, radiative efficiencies, and lifetimes of Ni screen/dielectric/Ni microdischarge devices, having overall thicknesses as small as <100 /spl mu/m and cylindrical microchannels 50-150 /spl mu/m in diameter, are investigated for Al/sub 2/O/sub 3/, BN, and BaTiO/sub 3/ dielectric films that are 120 or 200 /spl mu/m, 30 /spl mu/m, and 5 /spl mu/m in thickness, respectively. Having dielectrics fabricated by sol-gel processes or colloidal deposition and operated with Ne gas pressures between 300 and 1200 Torr (300K), these devices operate at voltages as low as /spl sim/93 V (100 /spl mu/m dia. BaTiO/sub 3/ device), and exhibit exceptional stability and lifetimes. After 100 h of continuous operation, a Ni screen/30 /spl mu/m BN/Ni device operating in 700 Torr Ne (static gas fill) at 100 V produces /spl sim/98% of its initial radiant output.     

Very high density RF MIM capacitors (17 fF//spl mu/m/sup 2/) using high-/spl kappa/ Al/sub 2/O/sub 3/ doped Ta/sub 2/O/sub 5/ dielectrics

Using high-/spl kappa/ Al/sub 2/O/sub 3/ doped Ta/sub 2/O/sub 5/ dielectric, we have obtained record high MIM capacitance density of 17 fF//spl mu/m/sup 2/ at 100 kHz, small 5% capacitance reduction to RF frequency range, and low leakage current density of 8.9/spl times/10/sup -7/ A/cm/sup 2/. In combination of both high capacitor density and low leakage current density, a very low leakage current of 5.2/spl times/10/sup -12/ A is calculated for a typical large 10 pF capacitor used in RF IC that is even smaller than that of a deep sub-/spl mu/m MOSFET. This very high capacitance density with good MIM capacitor characteristics can significantly reduce the chip size of RF ICs.     

RF Characteristics of a high-performance, 10-fF//spl mu/m/sup 2/ capacitor in a deep trench

We report the properties of a novel polysilicon-insulator-polysilicon trench capacitor with a 380-/spl Aring/ Si/sub 3/N/sub 4/ dielectric that is designed and fabricated for high-frequency bypass and decoupling applications. The capacitor has a specific capacitance as high as 10 fF//spl mu/m/sup 2/ normalized to its footprint area, and a breakdown voltage greater than 15 V at room temperature. The measured S-parameters are in excellent agreement with simulations of an equivalent circuit model that includes a shunt substrate resistance to ground (R/sub sub/). A geometric factor /spl mu/ is defined as the ratio of the imaginary parts of Y/sub 11/ and -Y/sub 21/ at low frequency. The values of /spl mu/ and, consequently, R/sub sub/ are extracted from fitting the measured S-parameter data, and the layout dependence of /spl mu/ and R/sub sub/ is also explained by the model.     

MIM capacitors using atomic-layer-deposited high-/spl kappa/ (HfO/sub 2/)/sub 1-x/(Al/sub 2/O/sub 3/)/sub x/ dielectrics

Metal-insulator-metal (MIM) capacitors with (HfO/sub 2/)/sub 1-x/(Al/sub 2/O/sub 3/)/sub x/ high-/spl kappa/ dielectric films were investigated for the first time. The results show that both the capacitance density and voltage/temperature coefficients of capacitance (VCC/TCC) values decrease with increasing Al/sub 2/O/sub 3/ mole fraction. It was demonstrated that the (HfO/sub 2/)/sub 1-x/(Al/sub 2/O/sub 3/)/sub x/ MIM capacitor with an Al/sub 2/O/sub 3/ mole fraction of 0.14 is optimized. It provides a high capacitance density (3.5 fF//spl mu/m/sup 2/) and low VCC values (/spl sim/140 ppm/V/sup 2/) at the same time. In addition, small frequency dependence, low loss tangent, and low leakage current are obtained. Also, no electrical degradation was observed for (HfO/sub 2/)/sub 1-x/(Al/sub 2/O/sub 3/)/sub x/ MIM capacitors after N/sub 2/ annealing at 400/spl deg/C. These results show that the (HfO/sub 2/)/sub 0.86/(Al/sub 2/O/sub 3/)/sub 0.14/ MIM capacitor is very suitable for capacitor applications within the thermal budget of the back end of line process.     

High-performance MIM capacitor using ALD high-k HfO/sub 2/-Al/sub 2/O/sub 3/ laminate dielectrics

For the first time, we successfully fabricated and demonstrated high performance metal-insulator-metal (MIM) capacitors with HfO/sub 2/-Al/sub 2/O/sub 3/ laminate dielectric using atomic layer deposition (ALD) technique. Our data indicates that the laminate MIM capacitor can provide high capacitance density of 12.8 fF//spl mu/m/sup 2/ from 10 kHz up to 20 GHz, very low leakage current of 3.2 /spl times/ 10/sup -8/ A/cm/sup 2/ at 3.3 V, small linear voltage coefficient of capacitance of 240 ppm/V together with quadratic one of 1830 ppm/V/sup 2/, temperature coefficient of capacitance of 182 ppm//spl deg/C, and high breakdown field of /spl sim/6 MV/cm as well as promising reliability. As a result, the HfO/sub 2/-Al/sub 2/O/sub 3/ laminate is a very promising candidate for next generation MIM capacitor for radio frequency and mixed signal integrated circuit applications.     

Metal-insulator-metal RF bypass capacitor using niobium oxide (Nb/sub 2/O/sub 5/) with HfO/sub 2//Al/sub 2/O/sub 3/ barriers

A high capacitance density (C/sub density/) metal-insulator-metal (MIM) capacitor with niobium pentoxide (Nb/sub 2/O/sub 5/) whose k value is higher than 40, is developed for integrated RF bypass or decoupling capacitor application. Nb/sub 2/O/sub 5/ MIM with HfO/sub 2//Al/sub 2/O/sub 3/ barriers delivers a high C/sub density/ of >17 fF//spl mu/m/sup 2/ with excellent RF properties, while maintaining comparable leakage current and reliability properties with other high-k dielectrics. The capacitance from the dielectric is shown to be stable up to 20 GHz, and resonant frequency of 4.2 GHz and Q of 50 (at 1 GHz) is demonstrated when the capacitor is integrated using Cu-BEOL process.     

Colloidal processing of polymer ceramic nanocomposite integral capacitors

Polymer ceramic composites form a suitable material system for low temperature fabrication of embedded capacitors appropriate for the MCM-L technology. Improved electrical properties such as permittivity can be achieved by efficient filling of polymers with high dielectric constant ceramic powders such as lead magnesium niobate-lead titanate (PMN-PT) and barium titanate (BT). Photodefinable epoxies as the matrix polymer allow fine feature definition of the capacitor elements by conventional lithography techniques. The optimum weight percent of dispersant is tuned by monitoring the viscosity of the suspension. The dispersion mechanism (steric and electrostatic contribution) in a slightly polar solvent such as propylene glycol methyl ether acetate (PGMEA) is investigated from electrophoretic measurements. A high positive zeta potential is observed in the suspension, which suggests a strong contribution of electrostatic stabilization. By optimizing the particle packing using a bimodal distribution and modified processing methodology, a dielectric constant greater than 135 was achieved in PMN-PT/epoxy system. Suspensions are made with the lowest PGMEA content to ensure the efficiency of the dispersion and efficient particle packing in the dried film. Improved colloidal processing of nanoparticle-filled epoxy is a promising method to obtain ultra-thin capacitor films (<2/spl mu/m) with high capacitance density and improved yield. Capacitance of 35 nF/cm/sup 2/ was achieved with the thinnest films (2.5-3.0 /spl mu/m).     

苯并噁嗪/钛酸钡复合材料介电性能的研究

通过共混法制备了苯并噁嗪/钛酸钡复合材料,探讨了钛酸钡粒径和填充量对复合材料介电性的影响。当?(BaTiO3)=50%时,复合材料介电常数εr达54、介质损耗tanδ为0.027、体积电阻率ρv大于1011?·m、击穿电压Vb大于8×103V/mm的高εr低tanδ绝缘材料。并将其应用于制备内嵌式电容器用玻璃布复合层压板。     

Effects of ${hbox{CNT/BaTiO}}_{3}$ Composite Particles Prepared by Mechanical Process on Dielectric Properties of Epoxy Hybrid Films

A new type of composite filler mechanically treated with multi-walled carbon nanotubes (MWNTs) and (BT) particles was prepared to produce higher dielectric properties in the composite. The hybrid film fabricated by incorporating these composite fillers in an epoxy matrix had a high dielectric constant and similar dielectric loss as compared to the composite which contained neat BT particles. The dielectric properties of these hybrid films were found to be dependent on both the content of MWNTs and mechanical processing time. Results suggest that this novel hybrid film composed of the composite filler and the epoxy matrix can be used for embedded capacitor material.     

A novel program-erasable high-/spl kappa/ AlN-Si MIS capacitor

We demonstrate a programmable-erasable MIS capacitor with a single layer high-/spl kappa/ AlN dielectric on Si having a high capacitance density of /spl sim/5 fF//spl mu/m/sup 2/. It has low program and erase voltages of +4 and -4 V, respectively. Such an erase function is not available in other single layer Al/sub 2/O/sub 3/, AlON, or other known high-/spl kappa/ dielectric capacitors, where the threshold voltage (V/sub th/) shifts continuously with voltage. This device exhibits good data retention with a V/sub th/ change of only 0.06 V after 10 000 s.     

RF, DC, and reliability characteristics of ALD HfO/sub 2/-Al/sub 2/O/sub 3/ laminate MIM capacitors for Si RF IC applications

High-performance metal-insulator-metal capacitors using atomic layer-deposited HfO/sub 2/-Al/sub 2/O/sub 3/ laminate are fabricated and characterized for RF and mixed-signal applications. The laminate capacitor can offer high capacitance density (12.8 fF//spl mu/m/sup 2/) up to 20 GHz, low leakage current of 4.9/spl times/10/sup -8/ A/cm/sup 2/ at 2 V and 125/spl deg/C, and small linear voltage coefficient of capacitance of 211 ppm/V at 1 MHz, which can easily satisfy RF capacitor requirements for year 2007 according to the International Technology Roadmap for Semiconductors. In addition, effects of constant voltage stress and temperature on leakage current and voltage linearity are comprehensively investigated, and dependences of quadratic voltage coefficient of capacitance (/spl alpha/) on frequency and thickness are also demonstrated. Meanwhile, the underlying mechanisms are also discussed.     

Contrast-enhancement in black dielectric electroluminescent devices

A high contrast electroluminescent (EL) device structure is presented. The diffuse luminous reflectivity from the metal/dielectric/phosphor/indium-tin-oxide/glass EL device structure is /spl sim/3%. A Eu-doped GaN phosphor is used to demonstrate the contrast-enhanced operation. Low reflectivity is achieved by inserting a light-absorbing black thick-film BaTiO/sub 3/ layer between the phosphor and the rear metal electrode. In addition to providing contrast enhancement, the opaque thick dielectric film exhibits capacitance and high voltage reliability (40 nF/cm/sup 2/, dielectric constant /spl epsi//sub d/ /spl sim/ 500-1000, breakdown field E/sub d,br/ /spl sim/ 0.1-0.4 MV/cm) similar to that of the highest performance transparent thin-film dielectrics. An EL device luminance of only 20 cd/m/sup 2/ is sufficient for a display contrast ratio of /spl sim/10:1 under 140 lux indoor ambient lighting (illumination). Under sunlight illumination of 100000 lux, a display contrast ratio of >3:1 is expected with application of additional contrast enhancement techniques.     

BaTiO3表面改性对其环氧树脂复合材料性能的影响

采用硅烷偶联剂KH550对BaTiO3粉末进行了表面改性,以提高BaTiO3-环氧树脂复合材料的性能.研究了钛酸钡颗粒的表面状态、复合材料的微观形貌和介电性能以及复合材料与铜箔问的结合力,探讨了表面改性影响复合材料电学和力学性能的作用机理.结果表明:BaTiO3的表面改性有利于BaTiO3在环氧树脂基体中的分散,提高了...     

Interfacial polarisation in Al-Y/sub 2/O/sub 3/-SiO/sub 2/-Si capacitor

The variation by a factor of 2 in the observed permittivity of yttrium oxide film is explained in terms of interfacial polarization based on the Y/sub 2/O/sub 3//SiO/sub 2/ double-layer model. Provided the dielectric relaxation time constants of the two layers are grossly dissimilar, the model can also explain the frequency independence of the composite capacitor.<>