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We demonstrate optical super-resolution (resolution better than conventional diffraction-limited resolution) in a simple optical configuration by using annular apertures to manipulate the pupil function of the system. The theoretical basis of the technique is described, and it is shown how good agreement between theory and experiment can be achieved by suitable selection of the principal system parameters. The ready implementation and suitability for theoretical interpretation makes the demonstration a good candidate for an undergraduate laboratory experiment in classical optics. [ABSTRACT FROM AUTHOR]

It has been known since 1959 that the focal-plane intensity distribution produced by focusing polarized light with a high-numerical-aperture lens should be highly asymmetric. Remarkably, the consequences of this fundamental effect in direct image acquisition have remained unexploited, although vectorial effects have been observed in the contexts of free-space focusing, molecular fluorescence and photolithography. By using extreme-numerical-aperture (values of 3.5), solid-immersion microscopy we have obtained images of a silicon integrated circuit showing, for the first time, the dramatic influence of polarization on their spatial resolution, with values from 100 nm to 250 nm. Our data show that polarization-sensitive imaging can substantially surpass the scalar diffraction limit embodied by classical formulae such as Sparrow's criterion. Such performance will have an impact on activities such as integrated-circuit failure analysis, where optical inspection faces serious challenges from the sub-100-nm feature sizes routinely used in production devices. [ABSTRACT FROM AUTHOR]

By inducing two-photon absorption within the active layer of a proprietary silicon test chip, we demonstrate here solid-immersion-lens-enhanced nonlinear frequency-variation mapping of a 500-MHz ring oscillator circuit at 1560 nm. This work compares the performance of conventional single-photon linear methodologies against advanced two-photon alternatives and reports a maximum laser-induced change in the oscillator stage-delay of approximately 1 ps, and a signal injection resolution of 260 nm. [ABSTRACT FROM AUTHOR]

We present experimental evidence for the resolution-enhancing effect of an annular pupil-plane aperture when performing nonlinear imaging in the vectorial-focusing regime through manipulation of the focal spot geometry. By acquiring two-photon optical beam-induced current images of a silicon integrated-circuit using solid-immersion-lens microscopy at 1550 nm we achieved 70 nm resolution. This result demonstrates a reduction in the minimum effective focal spot diameter of 36%. In addition, the annular-aperture-induced extension of the depth-of-focus causes an observable decrease in the depth contrast of the resulting image and we explain the origins of this using a simulation of the imaging process. [ABSTRACT FROM AUTHOR]

Three-dimensional subsurface imaging through the back side of a silicon flip chip is reported with a diffraction-limited lateral resolution of 166 nm and an axial performance capable of resolving features only 100 nm deep. This performance was achieved by implementing sample-scanned two-photon optical beam induced current microscopy using a silicon solid immersion lens and a peak detection algorithm. The excitation source was a 1530 nm erbium:fiber laser, and the lateral optical resolution obtained corresponds to 11% of the free-space wavelength. [ABSTRACT FROM AUTHOR]