Cooling challenges for silicon integrated circuits

Microprocessor design with varying styles and complexities exhibit power density gradients across the die. 300+ W/cm/sup 2/ local densities a.k.a 'hot spots' are seen and it is a continuing challenge to cool these hot spots in designing thermal solutions. Hot spots will exacerbate the cooling margin in system and packaging thermal solutions. Depending on the market segment (mobile, desktop, server) and feature densities in the system (HDD, Memory etc.), the industry faces the challenge of staying in cost effective air cooling regime. In the Enterprise space, the feature rich thin rack and blade servers are thermally pushing the limits or air cooling. Additionally, the 24/7 (24 hours, 7 days a week) use environment of servers demand highly reliable and often redundant cooling solutions and any new cooling strategy needs to meet or exceed the well established and industry accepted reliability expectations, common of air cooling solutions. The package solutions need to quickly spread the 'hot spot' heat to the next level and the system thermal solutions need to cost effective and highly reliable.