US Patent 7719109 Embedded capacitors for reducing package cracking

A linear coefficient of thermal expansion (CTE) mismatch between two materials, such as between a microelectronic die and a mounting substrate, may induce stress at the interface of the materials. The temperature changes present during the process of attaching a die to a mounting substrate can cause cracking and failure in the electrical connections used to connect the die and mounting substrate. A material with a CTE approximately matching the die CTE is introduced in the mounting substrate to reduce the stress and cracking at the electrical connections between the die and mounting substrate. Additionally, this material may comprise thin film capacitors useful for decoupling power supplies.