ABSTRACT
This chapter discusses the fundamentals of in-situ process and wafer-state sensors in original equipment manufacturer (OEM) tools, and their use in APC, as this is the path that semiconductor manufacturing now has to aggressively pursue. The purpose of this brief APC overview was to provide the context for this chapter on in-situ metrology. The chapter provides information for the in-situ sensors that are commercially available and are currently, or soon will be, used in OEM tools for the measurement and control of process state and wafer-state properties. Thermocouples are sometimes used for temperature measurement in processing tools. Optical temperature measurement is historically the primary method for in-situ wafer temperature sensing. The chapter describes an impulsive stimulated thermal scattering method for noncontact measurement of metal film thickness in semiconductor manufacturing and process control. Sensors exist for monitoring both the process state of a particular tool and the wafer state of the processed wafer.
