The most popular packaging option in more recent Xilinx devices is lidless packaging. There are two primary reasons for this. As previously mentioned, lidless devices generally have superior thermal performance as compared to lidded devices, so lidless devices are often preferred in addressing challenging thermal situations. Also, particularly for the larger package body devices, large package lids tend to deform over temperature, and overall reliability is challenging. On the other hand, lidless packages with stiffener ring have far fewer issues with overall coplanularity as we move to larger, multi-die packaging options.
As with lidded devices, we can further break down the lidless classification into three packaging types.