Abstract: A measurement system for measuring aspects of a wafer combines an apparatus for performing a conductivity measurement, such as a four-point probe system, with apparatus for performing an optical measurement, such as a photoacoustic measurement system. Results are obtained and combined to provide comprehensive data sets describing the characteristics of the thin film substrate therein.

Abstract: A metrology system has one or more central ‘metrology servers’ and one or more ‘metrology slaves’ The server delivers metrology ‘pump/probe’ signals to multiple slave systems allowing a reduction in the number of high-cost metrology components in the master system. In certain cases, multiple metrology components in the ‘master’ system may provide redundancy while still maintaining a beneficial cost benefit. Reliability can also be improved by using multiple lasers and multiple delay paths with a cross-point switch between them. If one sub-system goes down, the system may ‘serialize’ metrology operations and thereby maintain all systems running, although at somewhat of a reduced throughput. An important element of this invention is grouping all or most of the costly components in a centralized laser server, and issuing pump-probe pulse pairs to remote metrology heads through a light pipe or other conveyance, such as optical fiber.

Abstract: A metrology system has one or more central ‘metrology servers’ and one or more ‘metrology slaves’ The server delivers metrology ‘pump/probe’ signals to multiple slave systems allowing a reduction in the number of high-cost metrology components in the master system. In certain cases, multiple metrology components in the ‘master’ system may provide redundancy while still maintaining a beneficial cost benefit. Reliability can also be improved by using multiple lasers and multiple delay paths with a cross-point switch between them. If one sub-system goes down, the system may ‘serialize’ metrology operations and thereby maintain all systems running, although at somewhat of a reduced throughput. An important element of this invention is grouping all or most of the costly components in a centralized laser server, and issuing pump-probe pulse pairs to remote metrology heads through a light pipe or other conveyance, such as optical fiber.