High Voltage Multi-Layer Ceramic Capacitors for Use at High Temperatures

Multi-layer ceramic capacitors (MLCC) rated to 200Vdc for use at 200 o C were developed using a high temperature C0G dielectric technology compatible with nickel electrodes. To meet the need for improved pulse detonator performance larger case size (2824 to 4540) capacitors rated to 2000Vdc at 200 o C were then developed using this technology. The growing demand for higher temperature electronics capable of exploiting new reserves of oil and natural gas led us to develop a range of smaller case (0805 to 2225), high voltage designs (> 500V to 2000V). The electrical characteristics of these surface mounted MLCC, such as insulation resistance, voltage breakdown, impedance and ESR, are described. The basic properties of some selected capacitors are compared to MLCC made with precious metal electrodes at high temperatures to explain the performance enhancements of this new product range. Reliability data at 200 o C is presented for some MLCC examples from the new product range and the mechanisms associated with reliable high temperature performance are reviewed. This new range of MLCC will allow designers of high temperature electronics to realize reliable, miniaturized circuit designs with stable capacitance at high voltage and high temperature.