MEMpax glass substrates are a type of glass substrate used in the field of microelectronics and microelectromechanical systems (MEMS). They are made from a special type of low-expansion, ultra-pure borosilicate glass that is highly durable and resistant to thermal stress, making it ideal for use in high-temperature applications. This type of glass substrate is often used as a base for depositing thin films and for fabricating micro-scale structures such as transducers, sensors, and actuators. Additionally, the chemical stability and low thermal expansion of MEMpax glass make it an attractive material for use in high-performance microelectronics and optical applications.