Bubbler for constant vapor delivery of a solid chemical

Abstract

Indium containing compounds are used in many electronic and optoelectronic devices. Examples vary from InAlGaP/InGaP materials for red emitters and HBTs, to InGaAs/InAlGaAs/InGaAsP for long-wavelength telecommunication lasers. For metalorganic chemical vapor deposition (MOCVD) of these devices, the chemical precursor used for epitaxial growth is generally trimethylindium (TMIn). TMIn is a solid source precursor and therefore has several issues associated with its reproducible and reliable delivery from the bubbler to the reactor, especially at high molar flow rates. In this work we report results on extremely stable delivery of TMIn under various experimental conditions using a unique bubbler design which overcomes most of the delivery problems associated with solid sources. With this bubbler, named the Hiperloop, we are able to obtain stable TMIn flux with a consumption of greater than 92–95% at various experimental conditions. We concentrate on conditions which are considered challenging but can deliver high throughput such as low pressures, high carrier gas flow rates, and high source temperatures.