AVS 52nd International Symposium
    Manufacturing Science and Technology Wednesday Sessions
       Session MS-WeA

Paper MS-WeA4
Endpointing Chamber Clean by Calorimetric Probing of Plasma Effluent

Wednesday, November 2, 2005, 3:00 pm, Room 207

Session: Metrology & Process Control for Advanced Manufacturing
Presenter: I.S. Chen, ATMI
Authors: I.S. Chen, ATMI
J.W. Neuner, ATMI
J.J. Welch, ATMI
P.S.H. Chen, ATMI
F. DiMeo, ATMI
Correspondent: Click to Email
The semiconductor industry employs gas-phase cleaning widely to remove materials deposited on the chamber walls during thin film deposition processes. Chamber clean endpointing - i.e., terminating the process when the chamber is clean - is desirable to manage cost-of-ownership and environmental impact. Existing endpointing 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 endpointing. The probe has an all solid-state construction and is engineered to immerse in the plasma effluent during endpointing operation. The probe measures the heat flux carried by the effluent, and the signal has been shown to correlate with chamber condition. By virtue of its downstream location, the probe operation does not depend on the plasma sourcing scheme (in situ vs. remote). We demonstrate successful endpointing for in situ chamber clean of TEOS deposition process on a PECVD tool. The probe results compare favorably with other co-installed endpointing solutions.