US 11,718,912 B2
Methods and apparatus for calibrating concentration sensors for precursor delivery
Sarah L. White, Santa Clara, CA (US); Elaina Noelle Babayan, Sunnyvale, CA (US); and Weize Hu, Sunnyvale, CA (US)
Assigned to APPLIED MATERIALS, INC., Santa Clara, CA (US)
Filed by APPLIED MATERIALS, INC., Santa Clara, CA (US)
Filed on Jul. 17, 2020, as Appl. No. 16/932,107.
Claims priority of provisional application 62/880,623, filed on Jul. 30, 2019.
Prior Publication US 2021/0032751 A1, Feb. 4, 2021
Int. Cl. C23C 16/455 (2006.01)
CPC C23C 16/45557 (2013.01) [C23C 16/45544 (2013.01); C23C 16/45561 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method of controlling an amount of a precursor flowing into a deposition chamber from an apparatus for controlling precursor flow, comprising:
A. forming an enclosed volume having a known volume between an inlet and an outlet of the apparatus for controlling precursor flow, wherein the enclosed volume comprises an ampoule comprising the precursor and a flow-through cell of a sensor assembly, and wherein the enclosed volume is controlled to be isothermal at a known temperature sufficient to produce a portion of the precursor in a gaseous state within the enclosed volume;
B. measuring a signal from the sensor assembly and performing a calibration of the apparatus for controlling precursor flow based on the measured signal from the sensor assembly, a known vapor pressure of the precursor at the known temperature, and the known volume; and
C. flowing a carrier gas at an operative carrier gas flow rate through the inlet, through the ampoule, through the flow-through cell, and through the outlet into the deposition chamber, while measuring the signal from the sensor assembly, and determining an amount of the precursor flowing into the deposition chamber based on the operative carrier gas flow rate, the signal from the sensor assembly, and the calibration of the apparatus for controlling precursor flow, wherein the sensor assembly comprises an infrared light source, a visible light source, or an ultraviolet light source, and a corresponding detector.