Method and apparatus for making a vapor of precise concentration by sublimation

Abstract

Techniques for controlling a solid precursor vapor source are provided. An example method disclosure includes providing a carrier gas to a precursor material in a sublimation vessel, such that the sublimation vessel includes an inlet area and an outlet area configured to enable the carrier gas to flow through the precursor material, and at least one thermal device configured to add or remove heat from the sublimation vessel, determining a sublimation temperature value and a delta temperature value based on the precursor material and the carrier gas, setting a first temperature in the sublimation vessel based on the sublimation temperature value and the delta temperature value, such that the first temperature is measured proximate to the inlet area, and setting a second temperature in the sublimation vessel based on the sublimation temperature value, such that the second temperature is measured proximate to the outlet area.