Abstract: An optical processor is presented for applying optical processing to a light field passing through a predetermined imaging lens unit. The optical processor comprises a pattern in the form of spaced apart regions of different optical properties. The pattern is configured to define a phase coder, and a dispersion profile coder. The phase coder affects profiles of Through Focus Modulation Transfer Function (TFMTF) for different wavelength components of the light field in accordance with a predetermined profile of an extended depth of focusing to be obtained by the imaging lens unit. The dispersion profile coder is configured in accordance with the imaging lens unit and the predetermined profile of the extended depth of focusing to provide a predetermined overlapping between said TFMTF profiles within said predetermined profile of the extended depth of focusing.

Abstract: The present invention introduces a new technique allowing the fabrication of high-aspect ratio nanoscale semiconductor structures and local device modifications using FIB technology. The unwanted semiconductor sputtering in the beam tail region prevented by a thin slow-sputter-rate layer which responds much slower and mostly to the high-intensity ion beam center, thus acting as a saturated absorber funnel-like mask for the semiconductor. The protective layer can be deposited locally using FIB, thus enabling this technique for local device modifications, which is impossible using existing technology. Furthermore, such protective layers allow much higher resolution and nanoscale milling can be achieved with very high aspect ratios, e.g. Ti layer results in aspect ratio higher than 10 versus bare semiconductor milling ratio of about 3.

Abstract: The present invention introduces a new technique allowing the fabrication of high-aspect ratio nanoscale semiconductor structures and local device modifications using FIB technology. The unwanted semiconductor sputtering in the beam tail region prevented by a thin slow-sputter-rate layer which responds much slower and mostly to the high-intensity ion beam center, thus acting as a saturated absorber funnel-like mask for the semiconductor. The protective layer can be deposited locally using FIB, thus enabling this technique for local device modifications, which is impossible using existing technology. Furthermore, such protective layers allow much higher resolution and nanoscale milling can be achieved with very high aspect ratios, e.g. Ti layer results in aspect ratio higher than 10 versus bare semiconductor milling ratio of about 3.

Abstract: A process for manufacturing selectively doped heterostructure field-effect transistors (SDHTs), a desired wafer structure for SDHT fabrication and a method for isolating SDHTs on the wafer are disclosed herein. The wafer has epitaxial layers grown on a substrate. The layers are: a buffer layer of GaAs, a first spacer layer of AlGaAs, a donor layer of AlGaAs, a second spacer layer of AlGaAs, a first cap layer of GaAs, an etch-stop layer of AlGaAs and a second cap layer of GaAs. A protective layer of AlGaAs may then be grown on the second cap layer to protect the second cap layer from contamination or damage. Also a superlattice may first be grown on the substrate.This invention was made with Government support under contract No. F29601-87-R-0202 awarded by the Defense Advanced Research Projects Agency, and under contract No. F33615-84-C-1570 awarded by the Air Force Wright Aeronautical Laboratories. The Government has certain rights in this invention.