Ceramic Green Sheets Research Articles

Electron beam machining of ceramic green-sheets for multilayer ceramic electronic packaging applications

High power electron beams can be used to machine vias and interconnecting structures in ceramic green-sheets. The advantages of this technology are: direct maskless metallization, noncontact machining of high density via and interconnecting structures of fine dimensions. These features translate themselves into design and development of state of the art multilayer ceramic (MLC) packaging on a quick turn around basis from design to build. Electron beam technology offers accurate machining of three dimensional interconnecting line structures. Vias of aspect ratio > 3 and diameters as small as 30 μm have been fabricated.

Multilayer Piezoelectric Ceramic Actuator with Interdigital Internal Electrodes

A multilayer piezoelectric ceramic actuator with interdigital internal electrodes has been developed. The internal electrodes of this actuator are line electrodes which are printed on piezoelectric ceramic green sheets and stacked such that alternating electrode lines are displaced by one-half pitch. This actuator is displaced at right angles to the stacking direction due to the piezoelectric longitudinal effect. Therefore, it is possible to prepare a long ceramic actuator, which will be highly reliable in applications. In this work, we have obtained a displacement of 50 µm/DC350V and a generative force of 34.3 MPa for a 74-mm-long actuator. The reliability of this actuator is confirmed to have a long life of more than 1000 hours using applied voltage of DC350V at 25°C and 60%RH.

Prediction and Explanation of Aging Shrinkage in Tape‐Cast Ceramic Green Sheets

A simple test to predict linear shrinkage of tape‐cast green sheets as a function of time was developed. Shrinkage was found to correlate inversely with the amount of organic phase bound to ceramic particle surfaces. The test was developed for alumina green tapes with acrylic binder. The correlation was found to be independent of the medium used for the two slurry systems evaluated, water and toluene/ethanol. Treatments developed to dimensionally stabilize green sheets reduced shrinkage after 35 days of aging to less than 0.15%. Stabilization treatments involved heating and/or polymer swelling which facilitated the binding of organic phase to alumina particles, causing the tape to be in a more relaxed state.

Lead zirconate titanate ceramics and monolithic piezoelectric transformer of low firing temperature

Abstract The binary system lead zirconate titanate (PZT) ceramics and monolithic piezoelectric transformer (MPT) have been investigated. The sintering temperature of PZT ceramic could be reduced from about 1250°C to about 960°C by the addition of a small amount of lower melting frit which is composed of B2O3-Bi2O3-CdO. The properties of the material are: Kp = 0.52 − 0.58. Qm = 1000, ϵ T/33/ϵ0 = 800 − 1100, tgδ = 50 × 10−4 ρ = 7.56 − 7.64 g/cm3. The Ag/Pd = 80/20 internal electrodes of MPT were cofired with ceramic green sheets at a temperature of about 960°C. The experimental results show that MPT has very high voltage step up ratio, lower driving voltage. The alternating current no-load voltage step up ratio of 9000 has been obtained. It is 30–40 times higher than that of the conventional single layer piezoelectric transformer.

Ceramic Green Sheet Puncher Using Multilayer Piezoelectric Actuator

A computer controlled ceramic green sheet puncher system was investigated. The punching head was driven by a flight actuator with multilayers of piezoelectric ceramic. The system copes with an arbitrary via hole pattern. It can punch via holes 0.15 mm in diameter through a ceramic green sheet 0.1 mm thick. Punching speed is 40 ms/hole.

Application of Designed-Space Forming Technology

A completely new designed-space forming technology using ceramic green sheet technology and photolithographic technology has been developed for ceramics. With this technology, it is possible to make any fine space accurately and at will in ceramics. A monolithic ceramic ink jet head and a piezoelectric multilayer ceramic sound transducer were developed using this new technology. A piezoelectric ceramic material was used for these devices. Spaces for nozzles, pressure chambers and an ink chamber in the ink jet head and cabities in the ceramic sound transducer were formed in the piezoelectric ceramic body with photosensitive polymer by photolithographic technology. The ink jet head showed stable ink ejection action with low drive voltage. The ceramic sound transducer showed wide-band sound responce characteristics with low drive voltage. The new designed-space forming technology can be applied to many kinds of electronic ceramic components and devices. Using this technology, miniaturization and cost reduction can be achieved.

Multilayer Ceramic Capacitors Based on Pb(Mg1/3Nb2/3)O3

AbstractMultilayer capacitors were made from Pb(Mg1/3Nb2/3)O3 compositon by an usual technique: ceramic green sheets formed by slip casting method, printed with an 70% wt Ag- 30% wt Pd internal electrode and sintered at temperature ranging from 950 to 11OO°C. Chip capacitors exhibit large capacitance and temperature characteristics meet Z5U specification. Electrical properties of MLC based on PMN depend on specific parameters such as the average concentration of pyrochlore phase and perovskite phase, and the homogeneity degree of dielectric layers. Load humidity life tests show a degradation of some chips which can be connected with the formation of a surface layer rich in pyrochlore phase.

An Automated Tool for Multilayer Ceramic Green Sheet Personalization

The initial personalization of multilayer ceramic substrates begins with the formation of vias in the individual green ceramic sheets. A fully automatic computer-controlled tool to perform this function has been developed by IBM and is in operation on its manufacturing lines. The auto punch tool creates more than 40 000 vias of two different sizes (0.14 mm and 0.15 mm) in green ceramic sheets of two different thicknesses (0.20 mm and 0.28 mm). The positional distribution of the vias is on a 0.3 mm grid. Other than the grid the vias may be randomly distributed. Their positional accuracy is within 0.03 mm at 3σ. The vias are created at a rate of 1440 vias per second. All data needed to operate the tool and to create the vias flow automatically from a host computer (IBM 3081) through an area controller (IBM Series I) to the tool controller (IBM Series I). Manufacturing data concerning each individual green ceramic sheet are returned to the factory host computer.