Tape casting of high dielectric ceramic composite substrates for microelectronics application

The current device of miniaturization and higher device counts in IC (integrated circuit) packages has significantly increased the use of both multilayer ceramic packages (MLCP) and multilayer capacitors (MLC). Crucial to the production of these ceramic substrates is the use of a tape cater with precise control of tape thickness, uniformity and surface finishes. The control of green tape thickness is crucial in governing the properties of tape cast products. Currently, the production and accurate reproduction of smaller and thinner substrates are limited by several factors, one of which is the precise control of the green tape thickness. This is in turn influenced by the various processing parameters and formulation of the materials used. Tape casting was performed on a batch process type caster, and the tapes were cast using varying blade gaps and casting speeds. It can be concluded that a higher degree of accuracy in tape thickness can be obtained when casting at lower casting speeds. However, this accuracy decreases when thinner tapes are required, and the optimized use of an increasing casting speed would be needed to maintain this accuracy. An optimal setting between the casting speed and the blade gap setting is, therefore, needed in order to achieve accurate and reproducible results when performing tape casting. Determination of this optimum combination would depend on the required thickness of the final product.