Bonding of soda-lime glass microchips at low temperature

A simple, low-temperature bonding process is described for the fabrication of soda-lime glass microfluidic chips. Due to its chemical inertness and temperature stability, glass remains a popular material for microfluidic chips despite the advances that have been made with polymer materials. Conventional thermal bonding is performed over the course of 24 h at 600°C and requires a precise temperature-controlled furnace. Here we introduce a simple low-temperature alternative for the high-strength bonding of soda-lime glass wafers based on the use of diluted HF solution in combination with pressure at a temperature of 65°C.