Nanofocus Resolution with ADVACAM WidePIX Detectors
Achieving the limits of resolution in nanofocus X-ray inspection requires finding the most appropriate combination of X-ray detector and X-ray source. A joint project to explore the capabilities of their components was initiated by ADVACAM s.r.o from Prague and X-RAY WorX GmbH from Garbsen. The combination of ADVACAMís photon counting WidePIX detectors with the nanofocus tube XWT-190-TCNF yielded a performance even below the tubeís nominal resolution of 0.5 microns.

ADVACAM develops the WidePIX line of high-resolution detector arrays with 55 microns pixel size using Si or CdTe sensors. By specifying energy bins, a very high sensitivity and low noise, especially for low contrast material, can be achieved. During the experiments, Si sensors of 500 microns thickness were used to image resolution test charts.

X-RAY WorX has designed the product line TCNF of nanofocus X-ray sources for highest resolution CT applications. Special diamond-based transmission targets and an internal cooling of the electron optics allow for various applications in semiconductor industry and material science.

For the experiments, the tube and detector were set up on a granite base. The resolution test charts were mounted on a micro-manipulator. Different exposure times were evaluated. At 50 seconds exposure, the 0.4 microns line patterns of JIMA RT RC-02b and NTT-AT X-Reso-100 were clearly resolved at voltages of 150kV and 190kV. At 100kV the 0.5 microns pattern of JIMA RT RC-02b was resolved. These results undercut the nominal values specified by X-RAY WorX for the product line TCNF by 20% (at 150kV and 190kV).

The joint experiments of ADVACAM and X-RAY WorX showed an amazing improvement of low contrast resolution when working with a photon counting detector. By excluding parts of the X-ray spectrum from the image, the WidePIX detector offers better contrast and unveils structures otherwise covered by quantum noise.

ADVACAMís expertise covers semiconductor sensor manufacturing, micro packaging, radiation imaging cameras and development of imaging solutions for industrial and academic needs. ADVACAM commercializes Medipix technology that is under development at CERN, Switzerland.

About X-RAY WorX

X-RAY WorX concentrates on development and production of microfocus X-ray tubes for high resolution X-ray analysis. This technology is used in industries with highest demands for quality and security like electronics, aerospace and automotive industry. Furthermore, X-RAY WorX supports users of microfocus X-ray systems with a broad range of services ranging from preventive maintenance and repair to the supply of spare parts and trainings.