Abstract: A vacuum chamber deposits thin films on a substrate by sputtering a target. The beam of atoms or ions from the target is partially blocked by a shadow or adjustable uniformity mask, reducing the deposition rate onto the substrate. The adjustable uniformity mask has several adjustable fingers. The fingers extend or retract to enlarge or reduce the size of the mask. Each finger covers a different annular region or radius of the substrate. The deposition rate at different substrate radii is thus adjustable by the fingers. Several optical beams monitor the film transmittance at different substrate radii. A transmittance profile is continually generated during deposition. As deposition proceeds, radii with a thicker film have their fingers extended to reduce their deposition rate, producing a more uniform film thickness across all radii. Motors extend or retract the individual fingers.
Type:
Grant
Filed:
March 29, 2001
Date of Patent:
April 15, 2003
Assignee:
Super Light Wave Corp.
Inventors:
Paul Hsueh, Shyang Chang, Hans Schiesser, Michael Ma, Jack Hsu, Abraham C. Ma
Abstract: An integrated optical device has two waveguide layers that are patterned to provide 2-dimensional interconnected networks of waveguides. A filter layer between the two waveguide layers is made by sputter deposition of thin films with alternating indexes of refraction. Light traveling vertically through the filter layer experiences an interferometric effect. A deflecting bump is formed in the plane of the lower waveguide layer. The bump is isotropicly etched, undercutting a photo-mask over the bump, producing a rounded, concave profile to the bump. High-index material is deposited over the bump and patterned to form a waveguide that has light deflected by the bump upward. The filter is formed over the bump to receive the deflected light. The filter reflects some light back down to the bump to another waveguide in the first layer. Light transmitted vertically up through the filter is bent to the horizontal plane of the upper waveguide layer.
Abstract: Optical logic gates are constructed from Mach-Zehnder Interferometer (MZI) optical circuits. A multi-mode interference (MMI) splitter divides a continuous-wave input into two branches of the interferometer. Each branch has a semiconductor optical amplifier (SOA). When a logic input having a logic-high power level is applied to one of the SOA's, cross-phase modulation occurs in the SOA. The phase shift increases through the SOA. The branch coupled to the logic input has a relative phase shift of &pgr; compared with the other branch. When two branches with the &pgr; phase difference are combined, destructive interference occurs, producing a logic low. An MMI combiner or an equivalent phase shifter is used to combine the two branches. The MMI splitter adds a phase shift of &pgr;/2 to the upper branch but not to the lower branch, while the MMI combiner also adds &pgr;/2 shifts.
Type:
Grant
Filed:
August 14, 2001
Date of Patent:
February 18, 2003
Assignee:
Super Light Wave Corp.
Inventors:
Tzu-Yih Chu, Shyang Chang, Chi Au, Abraham C. Ma
Abstract: A novel semiconductor optical amplifier (SOA) can operate as an optical inverter as well as a power-restoring device. Together, an optical-OR and the optical inverter can provide a wide variety of high speed optical logic gates and functions. The optical inverter uses cross-gain modulation (XGM) to invert a modulated signal on a first input, to produce an inverted output. The inverse of the modulation is transferred from a first wavelength of the modulated first input to a second wavelength of a continuous-wave second input. A filter can then block the first wavelength, allowing the inversely-modulated second wavelength to be output as the inverted output. The first and second wavelengths are swapped in alternate inverters in a logic path. The Y-junction can be implemented as a Multi-Mode Interference (MMI) device.
Type:
Grant
Filed:
June 29, 2001
Date of Patent:
October 8, 2002
Assignee:
Super Light Wave Corp.
Inventors:
Tzu-Yih Chu, Shyang Chang, Chi Au, Abraham C. Ma
Abstract: A sputtering chamber has a target that moves with an orbital motion relative to an ion beam. An X-Y assembly allows for target movement in both the horizontal and vertical directions. The X-Y assembly has a base plate, an intermediate plate, and a target mounting plate that attaches to the target. The plates are connected together by bearing blocks that slide along rails in the X and Y directions. A rotating shaft has gears that rotate a center shaft through the base and intermediate plates. The rotating center shaft has an arm on its end that attaches to the target mounting plate. The arm produces an orbital movement of the target. Rather than simply rotating the target around the center shaft, the center of the target orbits around the center of the center shaft. Ion-beam wear is spread across the target surface, extending target life and improving deposition uniformity.