Search for content and authors
 

Circuit design for high temperature hybrid manufacturability

Milton Watts 

Quartzdyne, Inc., 1020 Atherton Drive, Salt Lake City, UT 84123, United States

Abstract

High-temperature hybrids have been demonstrated to be the most reliable packaging method for down-hole circuits which will be subjected to elevated temperatures, thermal cycling and/or high shock and vibration. However, one cannot simply take a standard surface mount circuit and repackage it in hybrid form and expect good results. The circuit designer must consider issues such as die availability and active component functionality at high temperature. Passive components may also need to be changed: considerations include the availability of resistors and capacitors of appropriate physical size in hybrid-compatible packages, component tolerances over the temperature range and the effects of aging on these components. Practical hybrid package size limitations are driven by ceramic processing capabilities, dimensional tolerances, and thermal expansion mismatch between the substrate, the components, and the outer package. Circuit size reductions are not always realized as allowances must be made for package wall thicknesses, I/O pins, clearance between components and clearance for automated wire bond tools. Ten years of continuous hybrid process development and extensive circuit reliability testing has exposed several limitations on assembly reliability. Lessons learned and statistical failure data will be presented.

 

Legal notice
  • Legal notice:
 

Presentation: Oral at HITEN 2007, by Milton Watts
See On-line Journal of HITEN 2007

Submitted: 2007-07-13 22:18
Revised:   2009-06-07 00:44