Metrosol Limited

Jordan Valley Semiconductors Ltd.

Matthew Weldon

Dale A Harrison

Phillip Walsh

Jeffrey B Hurst

Cristian Rivas

A calibration pad having multiple calibration sites is provided. A particular calibration site may be utilized until that particular site has been determined to have become unacceptable for further use, for example from contamination, in which case the calibration processes may then move to use a different calibration site(s) on the calibration pad(s). A variety of techniques may be utilized to provide the determination that a site is no longer acceptable for use. Movement may thus occur over time from site to site for use in a calibration process. A variety of criteria may be established to determine when to move to another site. Though the designation of a site as 'bad' may be based upon measured reflectance data, other criteria may also be used. For example, the number of times a site has been exposed to light may be the criteria for designating a site as bad. Alternatively the cumulative exposure of a site may be the criteria. Further, the plurality of calibration sites that are provided on the single calibration pad may be pre-evaluated so as to initially screen out unacceptable calibration sites prior to use. The techniques provided may be utilized in calibration processes which utilize a single calibration sample or processes which require a plurality of calibration samples.

Automated calibration methodology for VUV metrology system

A technique is provided for monitoring and controlling surface contaminants on optical elements contained within the optical path (or sub-path) of an optical metrology instrument. The technique may be utilized in one embodiment in such a manner as to not require that additional components and/or instrumentation be coupled to, or integrated into, existing metrology equipment. Surface contaminants on optical elements within an optical metrology instrument are monitored so that cleaning procedures can be performed as deemed necessary. The cleaning procedures may include the use of exposing the optical elements to optical radiation. The optical metrology instrument may be an instrument which operates at wavelengths that include vacuum ultra-violet (VUV) wavelengths.

Contamination monitoring and control techniques for use with an optical metrology instrument

A technique is provided for generating and subsequently monitoring the controlled environment(s) within an optical metrology instrument in such a manner as to minimize absorbing species within the light path of the metrology instrument and to minimize the build-up of contaminants on the surfaces of optical elements that may result in performance degradation. Both evacuation and backfill techniques may be utilized together along with a monitoring technique to determine if the environmental is suitable for measurements or if the environment should be regenerated. The optical metrology instrument may be an instrument which operates at wavelengths that include vacuum ultra-violet (VUV) wavelengths.

A technique is provided monitoring and removing contaminants from the surface of a sample that is being measured with an optical metrology tool. The monitoring and removing contaminants from the surface of a sample may occur prior to recording an optical response from said sample in order to ensure that accurate results are obtained. Contaminant layers may be quantified so that other measurements may be accurately obtained without requiring the removal of the contaminant layer. The contaminant layers may be removed through the exposure to optical radiation. Alternatively, properties of non-contaminant layers may be characterized by analyzing changes that occur in such layers by exposure to optical radiation. The optical metrology instrument may be an instrument which operates at wavelengths that include vacuum ultra-violet (VUV) wavelengths.

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Austin, TX, United States of America

Matthew Weldon