Sample transport device with integrated metrology

#The present disclosure relates generally to sample transport devices for semiconductor processing and, more particularly, to sample transport devices with integrated metrology.

#Process flows in modern semiconductor device fabrication lines utilize a multitude of fabrication steps performed by a series of semiconductor fabrication tools. In some cases, process flows may contain more than 800 process steps in a re-entrant flow among a set of process tools including over one thousand equipment units of over one hundred different types. Wafers in a process flow are typically moved through the process steps in sealable sample transport devices, or front opening unified pods (FOUPs), by an automated material handling system (AMHS) or an overhead material handling system (OHS). For example, once a fabrication or metrology tool has received a FOUP, the FOUP may be opened in a controlled environment, processed, and returned to the FOUP for pickup. In this regard, the FOUP provides a clean and protective environment for the storage and transfer of samples in a process flow.

#Further, process flows typically include sample metrology steps after one or more fabrication steps, which are typically performed on dedicated metrology tools. However, transport of the samples to and from the metrology tools for measurement decreases production throughput and may expose the samples to additional contamination risks. Therefore, it would be desirable to provide a system and method for curing defects such as those identified above.

#The numerous advantages of the disclosure may be better understood by those skilled in the art by reference to the accompanying figures in which:

#FIG. 1 is a conceptual view of an in-FOUP metrology system, in accordance with one or more embodiments of the present disclosure.

#FIG. 2 is a profile view of an in-FOUP metrology system having one or more interchangeable components for insertion into a FOUP, in accordance with one or more embodiments of the present disclosure.

#Reference will now be made in detail to the subject matter disclosed, which is illustrated in the accompanying drawings. The present disclosure has been particularly shown and described with respect to certain embodiments and specific features thereof. The embodiments set forth herein are taken to be illustrative rather than limiting. It should be readily apparent to those of ordinary skill in the art that various changes and modifications in form and detail may be made without departing from the spirit and scope of the disclosure.

#Embodiments of the present disclosure are directed to performing metrology measurements of samples within a sample transport device (e.g., a FOUP) with one or more integrated metrology tools. In this regard, an in-FOUP metrology system may perform metrology measurements on samples within an interior portion of the FOUP. It is noted herein that sample transport device and Front Opening Unified Pod (FOUP) are used interchangeably for the purposes of the present disclosure.

#It is recognized herein that semiconductor metrology is typically performed using dedicated metrology tools. Accordingly, samples must typically be transferred (e.g., by FOUPs) to and from the metrology tools in order to perform the associated metrology measurements, which may negatively impact the operational throughput. For example, a time cost associated with a measurement may include not only the time required by a metrology tool to perform a measurement, but also loading times of a sample into and out of a FOUP and transit times to and from the metrology tool. Accordingly, the frequency of measurements on a sample and/or the number of samples measured by a particular metrology tool may be determined by balancing the time cost associated with the measurement with the value (e.g., the utility) of the measurement. For this reason, metrology is typically limited to high-precision measurements associated with critical process steps.