Development of thin film resistors for use in multichip modules

Boeing´s current MCM-D process is based on polyimide dielectric and Cu interconnects passivated with thin film Ti. Materials and processes are being developed to integrate passive components (resistors, capacitors and inductors) into these MCM-D substrates in order to make further improvements in Boeing´s electronics technology. By embedding passive components into MCMs, the size, weight, and cost of MCMs can be minimized while improving performance and reliability. This paper describes the development of low value TaN_x resistor elements suitable for integration into MCMs. The criteria for the resistor fabrication technology was that it be based on thin film processing for compatibility with the MCM-D fabrication process. Development of both the TaN_x thin film deposition process and the patterned resistor fabrication process are discussed. X-ray analysis of the TaN_x film, resistor trimming, environmental test results, and integration into an MCM structure are also described