A study and actual test using LTS (Low Temperature Soldering) on SMT devices from Nexperia. Link here (PDF)
New generation Low Temperature Solder (LTS) pastes for Surface Mount Technology (SMT) is proposed for low temperature applications such as computing. LTS pastes are commonly build on near-eutectic SnBi alloying system and therefore show reduced melting temperatures which reduces the reflow temperatures as well as the energy consumption during SMT by up to 40%. This translates into reduced CO2 emissions and reduced manufacturing cost. Additionally, such effect can improve the yield impact created by high temperature (HT) warpage. HT warpage is widely recognized seen as main driver to reduce the reflow temperature for SMT. New product markets such as ultra-mobile computing and the Internet of Things (IoT) drive the need for smaller and thinner packages and boards which can suffer warpage by reflow temperatures of current solder systems like SAC. By lowering the peak temperature during reflow, warpage is reduced, resulting in higher SMT yields.