Showing papers by "Fred Barlow published in 2003"

Process and material challenges associated with the next generation of LTCC based products

Abstract: Current trends in electronics are driving demands to decrease the overall size of circuitry and increase the functionality. A variety of different substrate technologies have been proposed to meet these demands. Low Temperature Cofired Ceramics (LTCC) is one of many technologies that offer the potential to solve this problem. LTCC is a mature and robust technology that is finding wide spread adoption in a number of key applications. However, all substrate technologies are continually refined in order to expand the capabilities and therefore expand market adoption. While LTCC has many advantages, there are many challenges involved in processing future products with ever-decreasing circuit feature sizes. In order to effectively exploit the advantages offered by LTCC and meet these demands, advancements in the state of the art are needed. This paper will discuss in detail the current technology limitations as they pertain to high frequency circuits as well as high density interconnect substrates used for digital systems. The impact of tape instability, printing tolerance, embedded passives, as well as layer-to-layer alignment will be discussed including potential solutions.

LTCC based MEMS impingement coolers

Abstract: This paper deals with the cooling of high-density electronics using MEMS based impingement coolers. The coolers have been created from micro jet arrays based on both silicon micro machining and Low Temperature Co-fired Ceramic (LTCC). Some of the advantages of LTCC are that the technology offers hermeticity, matched thermal expansion coefficient (TCE) to minimize packaging-induced thermo mechanical stresses, and the ability to form cavities and other complex structures into the substrate material. Micro Jet Array (MJA) coolers have been fabricated and tested using both silicon, and hybrid silicon LTCC designs. In the present work, the demonstration of the hybrid technology incorporating both the Si and the LTCC fabrication techniques is discussed. The fabrication of the MJA in LTCC offers many advantages when compared to the conventional silicon based MJA. The limitations of the silicon based micro jet array are the wafer thickness required to withstand the inlet air pressure and the difficulties associated with bonding multiple wafers. In comparison the LTCC based design has the potential to be lower in cost and is much simpler to manufacturer.