The semiconductor industry employs gas-phase cleaning widely to remove materials deposited on the chamber walls during thin-film deposition processes. Chamber clean end-pointing-i.e., terminating the process when the chamber is clean-is desirable to manage cost of ownership and environmental impact. Existing end-pointing methods tend to rely on changes of plasma characteristics as the in situ plasma removes the deposit in time. Chamber clean technology is moving towards remote generation of plasma species for cleaning. In this arrangement, the chamber is located downstream from the plasma source. Because the etching reaction occurs ex situ, there are no relevant changes occurring in the plasma characteristics, and the effectiveness of many existing methods decreases. We report the development of a calorimetric probe for chamber clean end-pointing. The probe has an all solid-state construction and is engineered to be immersed in the process effluent during end-pointing operation. When the probe is operated at constant temperature, the probe power is closely related to the energy flux carried by the effluent, which in turn correlates with chamber conditioning. We examine probe response to NF3 plasma and etching of silicon specimens in a laboratory setting, and demonstrate successful end-pointing, for both in situ and remote chamber clean on production tools. The probe results compare favorably with other coinstalled end-pointing solutions. (c) 2006 American Vacuum Society.