Qinetiq Limited

Oxford Instruments Nanotechnology Tools Limited

Mark Edward McNie

Richard Michael Jenkins

Kevin Michael Brunson

Keith Loder Lewis

Andrew Maxwell Scott

James McQuillan

David J Combes

Gilbert William Smith

Craig D Stacey

David James Hamilton

Leslie Michael Lea

Christopher William Slinger

Michael Cooke

David O King

Vishal Nayar

Kevin Dennis Ridley

David J Jackson

Robert John Tremayne Bunyan

Nicola Price

Methods are disclosed for depositing material onto and/or etching material from a substrate in a surface processing tool having a processing chamber, a controller and one or more devices for adjusting the process parameters within the chamber. The method comprises: the controller instructing the one or more devices according to a series of control steps, each control step specifying a defined set of process parameters that the one or more devices are instructed to implement, wherein at least one of the control steps comprises the controller instructing the one or more devices to implement a defined set of constant process parameters for the duration of the step, including at least a chamber pressure and gas flow rate through the chamber, which duration is less than the corresponding gas residence time (T) of the processing chamber for the step.

Methods and apparatus for depositing and/or etching material on a substrate

A variable optical attenuator device is described that comprises a first optical input, a first optical output, a first optical path between the first optical input and the first optical output, and means for moving a shutter across said first optical path. A hollow core waveguide is provided to substantially guide light along the first optical path of the device. The device may also be used to provide an analogue beam splitting or switch function in telecommunication systems and the like.

Variable optical attenuator comprising hollow core waveguide

A retro-reflective identification tag capable of modulating an optical signal whereby to support bi-directional communication with an associated remote optical interrogation device. The tag comprises a MOEMS modulating layer over a retro-reflective substrate, giving the tag a wide angle of effective operation. The tag modulator may optionally be switched on only responsive to detection of a precursor beam from the interrogation system in order to save power. The interrogation device may make use of multiple optical wavelengths for communicating with the tag.

Dynamic optical reflector and interrogation system

An optical routing device is described that comprises a semiconductor substrate () having at least one optical input (), a plurality of optical outputs () and an array of MEMS moveable reflective elements (). The array of moveable reflective elements () are configurable such that light can be selectively routed from any one optical input () to any one of two or more of said plurality of optical outputs (). Light selectively routed from any one optical input to any one of two or more of said plurality of optical outputs () is guided within a hollow core waveguide (). In one embodiment, a cross-connect optical matrix switch is described.

Optical routing device comprising hollow waveguides and MEMS reflective elements

A transmitter apparatus () is described that comprises one or more lasers (), modulation means () to intensity modulate radiation output by each of said one or more lasers (), and output means for outputting the modulated radiation produced by the modulation means into, for example, an optical fiber (). The apparatus comprises hollow core optical waveguides () formed in a substrate () which, in use, guide radiation from the one or more lasers () to the modulation means () and from the modulation means () to the output means. An associated receiver apparatus () is also described that comprises one or more detectors () and one or more optical fiber attachment means, the one or more optical fiber attachment means being arranged to receive one or more one optical fibers (). The receiver is characterized in that radiation is guided from the one or more optical fibers () to the one or more detectors () by at least one hollow core optical waveguide () formed in a substrate. A combined receiver/transmitter apparatus () is also shown.

Monolithic optical transmitter and receiver apparatus incorporating hollow waveguides

A micro-opto-electro-mechanical systems (MOEMS) electro optical modulator () having an electrically tuneable optical resonator comprising an asymmetric Fabry-Perot etalon incorporating a mirror () resiliency biased with respect to a substrate () and moveable in relation thereto in response to a voltage applied there-between. The optical modulator () is capable of modulating electromagnetic radiation having a plurality of wavelengths. The modulator is adapted to modulate the transmission of short wave infrared radiation (SWIR), medium wave infrared radiation (MWIR) and long wave infrared radiation (LWIR) and the reflection of visible radiation. A spatial optical modulator having a plurality of said MOEMS optical modulators (). A method of addressing said spatial optical modulator.

Optical modulator

An optical modulator comprising a spacing-controllable etalon having at least one sprung micro-mirror suspended above a substrate. At least one electrically insulating stop is provided between the micro-mirror and the substrate to avoid short-circuit when the micro-mirror is drawn towards the substrate by an applied voltage. An optical detector detects the time of arrival of a first laser pulse. A control circuit predicts from this an arrival time of the next incident laser pulse and, responsive to a control signal, either retains the micro-mirror in its pulled-down state held against the insulating stops or releases the micro-mirror at a time predicted to maximise or minimise the light transmitted through the modulator. After a time interval calculated to permit a predetermined number of mechanical oscillations, the micro-mirror is pulled back down onto the stops.

Optical modulation

An optical wavelength division multiplexer/demultiplexer device is described that comprises a substrate having a plurality of wavelength selecting filters. The filters are arranged to provide conversion between a combined beam comprising a plurality of wavelength channels and a plurality of separate beams each comprising a subset of said plurality of wavelength channels. Hollow core waveguides are formed in said substrate to guide light between the wavelength selecting filters. An add/drop multiplexer is also described.

Optical wavelength division multiplexer/demultiplexer device

A photonic light circuit device is described that comprises a semiconductor substrate () and two or more optical components () wherein one or more hollow core optical waveguides () are formed in the semiconductor substrate to optically link said two or more optical components. The PLC may comprise a lid portion () and a base portion (). The PLC can be adapted to receive optical components () or optical components may be formed monolithically therein. Coating with a reflective layer is also described.

Optical circuit fabrication method and device

A hollow core multi-mode interference (MMI) device is described that comprises a multi-mode waveguide () optically coupled to at least two fundamental mode waveguides (). The device is characterised in that it comprises a means for varying the internal cross-sectional dimensions of a portion of one or more of said at least two fundamental mode waveguides. In particular, the side wall of a fundamental mode waveguide having a substantially square cross-section can be moved using micro-electro mechanical systems (MEMS). Various optical routing devices incorporating such MMI devices are described.

Hollow core multi-mode interference optical device

An optical amplifier is described that comprises at least two sections of amplifying optical fibre and pumping means for optically pumping the amplifying optical fibre. Optical fibre support means, for example a channel or channels in a substrate, are also provided to hold the two or more sections of amplifying optical fibre substantially straight during use. The optical fibre support means also includes a means for coupling light between the at least two sections of amplifying optical fibre. The at least one amplifying optical fibre may comprise an Erbium doped core to provide an erbium doped fibre amplifier (EDFA).

Optical fibre amplifier

A MEMS incorporating a sensing element and a JFET electrically connected to the sensing element is fabricated by the steps of: forming a first layer of electrically insulating barrier material on a surface of a substrate; patterning the first layer so as to expose a first region of the substrate; doping by ion implantation the first region of the substrate to form a well region of the JFET; forming a second layer of barrier material on the surface of both the first layer and the first region of the substrate; patterning the barrier material so as to expose a part of the first region of the substrate; doping by ion implantation the exposed part of the first region of the substrate to form source and drain contact areas of the JFET; patterning the barrier material so as to expose a second region of the substrate; and doping by ion implantation the second region of the substrate to form gate and substrate contact areas of the JFET in a single implantion step. The monolithic integration of the JFET with the MEMS enables the bond wires for interconnecting the sensing element and the associated sensing electronic circuitry to be provided only after the buffering stage of such circuitry. This means that the bond wires interconnecting the buffering stage and the remainder of the circuitry are connected to a low impedance node which is less sensitive to noise and parasitic capacitive loading. Thus greater detection accuracy can be achieved by virtue of the fact that the parasitic capacitances are reduced to a minimum.

Method of fabricating micro-electromechanical systems

Optical circuits for optical amplifier input and output stages are described. The input stage circuit () comprises a first optical waveguide () for carrying a signal beam to be amplified, a second optical waveguide () for carrying a pump beam, a beam combining means () optically coupled to the first and second optical waveguides () for producing a combined signal/pump beam, and means for optically coupling the combined signal/pump beam into an amplifying optical fibre (). The output stage circuit () comprises a first output optical waveguide (), an optical fibre attachment means arranged to receive an amplifying optical fibre () and an optical fibre attachment means arranged to receive an output optical fibre () wherein light from the amplifying optical fibre () is optically coupled to the output optical fibre () via the first output optical waveguide (). The first and second optical waveguides () and the first output optical waveguide () are hollow core optical waveguides formed as channels in a substrate. A fibre amplifier, in particular an erbium doped fibre amplifier, comprising such optical circuits is also described.

Optical amplifier

A micro-electromechanical system (MEMS) comprises a substrate incorporating an oscillatory ring, forcing electrodes for driving the ring into resonance, and sensing electrodes providing an electrical output signal dependent on oscillation of the ring as a result of such forcing and any externally applied force. A positive feedback circuit is provided for feeding back a signal dependent on the output signal of the sensing electrodes to the forcing electrodes in order to sustain oscillation of the ring. The use of positive feedback to drive the forcing electrodes in order to sustain oscillation of the ring is highly advantageous in such an application since it produces a system which exhibits very low phase noise of a magnitude considerably less than the phase noise experienced in use of a phase-lock loop circuit to sustain oscillation.

Micro-electromechanical systems

A multi-mode interference (MMI) device, comprising a hollow core multi-mode waveguide optically coupled to at least one hollow core input waveguide, is described in which the internal surfaces of the hollow core waveguides carry a reflective coating. The coating may be a low refractive index material at the wavelength of operation, such as a metal, or a multiple layer dielectric stack. Resonators and optical amplifiers using such (MMI) devices are also described.

Growing community of inventors

Malvern, United Kingdom

Mark Edward McNie