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Measurement of surface finish in industrial manufacturing has traditionally been done by means of either visual comparison with reference plates or by the use of contact stylus based profilers. There are many challenges associated with contact profilers such as stability during measurement in an industrial environment, damage and wear of the tip, measurement in tight spaces or on curved surfaces and just the limited amount of data obtained by a linear scan of the stylus. Many alternative methods have become available such as white light interferometry, focus based systems, and even laser scatter. This paper will present the result of testing of the commercially available methods with particular emphasis on the fine surface finishes demanded in today's manufacturing, then presents some alternative methods that show strong potential to address some of the challenges mentioned above that are not in wide use today. The analysis will specifically explore some of the physical mechanisms that affect the stylus based measurement, as well as the limitations of many of the optical approaches related to view angle and diffraction limited resolution consequences. The area of confocal imaging will be specifically explored as to how it might be used to obtain more complete data on very fine surface finishes.

Characterization of a surface shape and finish has been vital for the manufacture of precision parts. Overall profile, surface finish and waviness of a part can be measured in two ways, contact and non-contact. In the contact method a stylus is dragged on the surface of a part to measure the profile and texture of the part for quantifying the surface characteristics. Non-contact methods applied z precision metrology include: microscopy, interferometry, chromatic confocal microscopy and laser profiling such as structured light methods. The chromatic confocal method offers flexibility because of its fiber optics probes that can be manipulated to accommodate many sample geometries. This flexibility provides a wide range of possible analysis dimensions such as cylindrical shapes of holes and the potential to provide both surface roughness and shape. This paper will discuss the setup and testing of a system specifically for measuring cylindrical shaped parts and present the performance of the technology as a precision metrology tool.

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Cadmium Zinc Telluride (CZT) based radiation detectors have been developed over the past decade and are, increasingly, being used in security and healthcare applications. Improvements in radiation detector performance, size, and cost have been achieved; however, the manufacturability and reliability of the individual CZT detector package continues to limit widespread use and new applications. To date, most CZT detector packages are designed, manufactured, and tested to requirements defined by manufacturers, rather than military, commercial, or industry standards, as is common for semiconductor packages. The lack of test standards has led to use restrictions and/or complex detector system design, as required to mitigate unknown or low detector package reliability. CZT detector packaging, as was the case for semiconductor packaging, has reached the point in technology maturation where a focus on optimizing detector design for manufacturability and reliability is appropriate and necessary. This paper reviews the systematic approach, including design, process development, and testing, utilized in the development and demonstration of a highly manufacturable and reliable (95% reliability at 1000 cycles) CZT detector package. Finite Element Model (FEM) based design and material trade-off studies, development of highly manufacturable and reliable commercial electronic assembly processes, failure mode identification and mitigation, selection and use of reliability test standards, and analyses are detailed for a flip-chip-CZT-on-ceramic substrate, detector package targeted for field deployment. As well, the next steps in package and system design, manufacturing, and reliability testing are proposed.