The most common package used in AMD devices for over 10 years is lidded flip chip packages. Lidded flip chip packages offer very good power and signal integrity, and improved junction to board and junction-to-case thermal resistance as compared to wire bond packages. The lids are generally constructed from a nickel plated copper material. TIM1 is a thermal interface material applied by AMD within the lidded device package to thermally couple the die to the device lid. This material ensures good coverage as well as good thermal conductivity to further improve the junction to case thermal performances. While the TIM1 applied in lidded flip chip packages offers optimal thermal performance across a wide range of applications and industries, it must also be able to withstand the high temperatures of solder reflow. This means while it is optimal, it might not perfectly meet your requirements for high power or high ambient applications. In comparison, lidless packages allow you to select the TIM based on your requirements and it is applied after the solder re-flow process. There are two types of lids used in AMD lidded flip chips, and it is good to become familiar with this for mechanical fit and to evaluate thermal properties.