The standard microfluidic device using membrane valves includes designing a control mold which has control channels of height A and a flow mold which has flow channels of height B. However, some applications The Stanford Microfluidics Foundry is able to bond PDMS chips to glass substrates (i.e. glass slides, cover-slips or chips) or silicon substrates (i.e. Si chips). There are three main methods for bonding your PDMS chip to a substrate.

•  Direct Thermal Bonding To Substrate

This method requires your substrate to withstand 80C. Devices sealed to glass are only rated to approximately 6psi flow pressures before delamination results. 

•  Bonding To Substrate Coated with PDMS

For this method, your substrate is coated by a thin layer of PDMS and the PDMS chip is directly bonded to this surface. Devices are rated to 20psi pressure.

•  Direct Bonding Via Oxygen Plasma

The chip may also be bonded to a glass substrate directly via plasma bonding and is rated to at least 20psi. If any part of your chip which may be at risk for collapses to occur, plasma bonding is not recommended.