1. TSMC is reportedly developing rectangular substrate carriers to support larger interposer sizes, aiming to address the growing demand for larger compute chiplets and HBM chips. 2. The current production of interposers on traditional round wafers results in limited yields due to the increasing size requirements of modern chips. 3. TSMC's move towards larger, rectangular substrates could significantly increase the number and size of interposers that can be produced, potentially alleviating supply constraints.