John Bultitude

SMD and Leaded Ceramic Capacitors for High Temperature Applications

For high temperature applications at 150°C or above, such as in electronics for down-hole drilling, geothermal energy generation, power electronics and automotive under the hood electronics, a robust dielectric material is necessary for capacitors. Common X7R and X8R type ceramic capacitors are designed for applications up to 125°C and 150°C, respectively. At temperatures above 150°C, these types of capacitors typically suffer from degradation of reliability performance and severe reduction in capacitance, especially under DC bias conditions. Recently, a Class-I dielectric material has been developed using Nickel electrodes for high temperature application up to 200–250°C. Due to its linear dielectric nature, this material exhibits highly stable capacitance as a function of temperature and voltage. Multi-layer ceramic capacitors (MLCCs) made from this material can be qualified as X9G. This paper will report electrical properties and reliability test data on these Class-I type ceramic capacitors in SMD chi...

An evaluation of BME C0G multilayer ceramic capacitors as building blocks for DC-Link capacitors in 3-D power electronics

Multilayer ceramic capacitors manufactured with different designs using a C0G Ni BME technology are evaluated as building blocks for DC-Link capacitors. Electrical and physical properties are compared to a commercially available DC-Link ceramic capacitor. Reliability evaluations at 600V and 200°C show that capacitors made with the C0G Ni BME have excellent reliability as well as high current handling capability that result in high power density. These properties coupled with high modulus of rupture, good board flexure resistance and thermal cycling capability make them excellent candidates for building blocks in 3D power electronics to meet higher temperature, voltage and switching frequency requirements. The benefits and limitations of transient liquid phase sintering materials and processes to replace solders for packaging are discussed.

Advanced Ceramic Capacitor Solutions for High Temperature Applications

For high temperature applications at 150°C or above, such as those in electronics for down-hole drilling, geothermal energy generation and power electronics, a robust dielectric material is necessary for capacitors. Ceramic capacitors using X7R and X8R type dielectrics are designed for applications up to 125°C and 150°C, respectively. At temperatures above 150°C, these X7R/X8R types of ceramic capacitors typically suffer from degradation of reliability performance and severe reduction in capacitance, especially when bias is applied. Recently, a Class-I dielectric material has been developed using Nickel electrodes for high temperature application up to 200–250°C. Due to its linear dielectric nature, this material exhibits highly stable capacitance as a function of temperature and voltage. This paper will report electrical properties and reliability test data on these Class-I type ceramic capacitors in SMD chip and leaded configurations at 150–200°C and above, and discuss possible mechanisms behind the rob...