Abstract: A high-sensitivity optical system to determine and/or control spatial displacement and position of objects applicable to various situations when a contact measurement cannot be performed, such as in high-vacuum or ultra-high vacuum chambers, at high temperatures, in aggressive chemical environments, etc. A laser beam is directed at a low glancing angle to a screen secured to an object. The screen's surface is normal to a motion direction of interest. A location of the bright laser beam spot on the screen surface is acquired and the displacement thereof is analyzed and quantified based on the change in distance from the laser beam spot to a reference element which is arranged on the screen and creates a variation in the acquired image brightness. A feedback loop control mechanism is provided which returns the displaced object to its original position.

Abstract: System and method for determining the composition of deposited thin films by acquiring multiple sequential X-ray spectra for a film of interest during the deposition process as the film thickness increases, computing intensities of peaks found in the X-ray spectra corresponding to elements present in the film material, followed by computing, for each pair of elements, ratios of corresponding peak intensities, graphing the intensities and ratios against a parameter correlated to the film thickness, and applying a physically meaningful function to the graphed data for best fitting the data down to a ratio RA/B(0) for each pair of the elements for a virtual film of zero thickness. Elemental concentrations ratio for each pair of elements is subsequently computed as a product of RA/B(0) and a factor which is specific for the pair of elements, constant for the instrument as set up, and independent of elements concentrations, and of film thickness.

Abstract: Non-destructive localization of open defects in electronic devices is performed with a DC SQUID based RF magnetometer capable of sensing coherent magnetic fields up to 200 MHz and higher. RF magnetic fields (or RF current) images are correlated to conductive paths layout of the electronic device, and the open defect is pinpointed at a location of RF current disappearance on the current image. The bandwidth limitations associated with transmission line delays between SQUID circuit and readout electronic, as well as with near-field coupling between different parts of the measurement scheme, are overcome by superimposing the RF flux emanating from device under study on the modulation flux to produce at the SQUID output a binary phase modulated RF voltage, which is processed to lock the static flux, and to control modulation regime by producing an AC bias for the RF flux.

Abstract: An RF DC SQUID based magnetometer capable of sensing coherent magnetic fields up to 200 MHz and higher is developed which overcomes frequency limitations associated with noise signals due to transmission line delays between the SQUID circuit and readout electronics. The bandwidth limitations are overcome by superimposing the RF flux on the modulation flux to produce at the SQUID output a binary phase modulated RF voltage, which is processed to lock the static flux, and to control modulation regime by producing an AC bias for the RF flux. RF readout electronics based on a double lock-in technique (sequential demodulation of the RF SQUID voltage at the modulation flux frequency ?m and the RF flux frequency ?RF), yields a signal proportional to the product of amplitude and phase cosine of RF flux with linear dynamic range up to five orders in magnitude if compared to DC SQUID operated in traditional flux-locked loop regime.

Abstract: An RF DC SQUID based magnetometer capable of sensing coherent magnetic fields up to 200 MHz and higher is developed which overcomes frequency limitations associated with noise signals due to transmission line delays between the SQUID circuit and readout electronics. The bandwidth limitations are overcome by superimposing the RF flux on the modulation flux to produce at the SQUID output a binary phase modulated RF voltage, which is processed to lock the static flux, and to control modulation regime by producing an AC bias for the RF flux. RF readout electronics based on a double lock-in technique (sequential demodulation of the RF SQUID voltage at the modulation flux frequency ?m and the RF flux frequency ?RF), yields a signal proportional to the product of amplitude and phase cosine of RF flux with linear dynamic range up to five orders in magnitude if compared to DC SQUID operated in traditional flux-locked loop regime.

Abstract: High quality GaN films exhibiting strong room temperature blue photoluminescence with negligible impurity emissions are grown by a Pulsed Laser Deposition process in which process parameters are controlled to attain plasma particle energy of a target material plume directed from the target on the substrate structure below 5 eV at the deposition surface. Among the process parameters, a distance between the deposition surface and the target, a pressure level of the reaction gas in the processing chamber, and an energy density of the pulsed laser beam directed to the target are controlled, in combination, to attain the required low plasma particle energy of the plume below 5 eV in vicinity of the deposition surface.

Abstract: A pulsed electron ablation (PEA) utilizes a source of a high power density electron beam which includes a cathode plasma supplying electrons for generation of the electron beam and an anode plasma having a front layer extending in the processing chamber in a counter relationship with the front layer of the cathode plasma. A gas supply line is coupled to the processing chamber to supply a process gas in a controlled fashion to the anode to create a pressure gradient between the anode and the cathode plasma, and to stimulate an intense ionization of the process gas in the vicinity to the anode to form the anode plasma. The power density of the electron beam sharply increases as the result of an interaction of said cathode and anode plasmas at the double space charge contact layer formed between their fronts. A target is positioned in the processing chamber a predetermined distance from the front layer of the cathode plasma and is exposed to the electron beam to produce stream of the ablation plasma.

Abstract: A radiative heater for substrates in a physical vapor deposition process for fabricating films of materials in a wide dynamic range of process temperatures and gas pressures includes a heat radiating member made from a high-temperature and oxidation resistant material tolerant to vacuum conditions which separates a heater volume containing heating filaments from a process volume which contains a deposition substrate heated by radiation of the walls of the heat radiating member. The heating elements extend through the body of the heat radiating member as well as in proximity to its surface to provide delivery of the heat to the substrate. The heat radiating member is shaped to form a cavity containing the substrate. The walls of the cavity envelope the substrate and radiate heat towards the substrate. Alternatively, the substrate is adhered to the flat surface of the heat radiating member.

Abstract: A scanning microscope for high resolution current imaging by direct magnetic field sensing of a sample maintained in an ambient environment. The scanning microscope uses a magnetic sensor such as a SQUID and a fiber probe magnetically coupled between the SQUID sensor and the sample under study. The fiber probe has a sharply defined tip for high resolution probing and for reaching minute cavities on the surface of the sample. The coupling between the tip of the fiber probe and the sample is controlled by a distance control mechanism, in the range of 1-100 nm. The material of the fiber probe with high permeability and low magnetic noise is chosen to optimize flux transmission to the magnetic sensor. Magnetic coupling to the sensor is maximized by keeping the distance between the end of the fiber probe and the sensor to approximately 0-100 ?m. The fiber probe is integrated into the fiber holder for easy replacement of the fiber probe.

Abstract: A heater for the non-contact heating of an object, such as a substrate for material deposition, includes a housing defining a deposition cavity and a source of radiation outside the deposition cavity. A reflector is optically coupled to the source of radiation to collect the radiation and to focus it on the radiation path. The reflector may have different shapes. If, for example, the reflector is an ellipsoidal reflector, the source of radiation then is mounted in a first focus, the substrate is located in the other focus, and the radiation path is positioned on the main focal axis of the ellipsoidal reflector. The radiation from the source of radiation is delivered to the substrate inside the deposition cavity through a radiation path(s) formed in the housing wall to heat the substrate to the temperature Ts, so that T1<Ts<T2, where T1 is the temperature of the housing wall, while T2 is the effective temperature of the source of radiation.