Buffered oxide etchant (BOE) 6:1 with surfactant

Buffered oxide etchant (BOE) 6:1 with surfactant may be used in the oxide removal of AlGaN/GaN-based high electron mobility transistors for gate photolithography. It may also be used in a buffer oxide etchant method for the fabrication of micro biochip.

Buffered oxide etchant (BOE) is a wet etchant used in microfabrication. Its primary use is in etching thin films of silicon dioxide (SiO₂) or silicon nitride (Si₃N₄). It is a mixture of a buffering agent, such as ammonium fluoride (NH₄F), and hydrofluoric acid (HF). Concentrated HF etches silicon dioxide too quickly for good process control and also peels photoresist used in lithographic patterning.