Abstract: RPCVD apparatus for forming a film is disclosed including a showerhead having at least one gas chamber, one or more plasma inlets to deliver plasma from one or more plasma generators into a reaction chamber; and a plurality of gas inlets to deliver gas from at least one gas chamber into the reaction chamber. At least one of the plasma inlets is located at a position that is between a central region and an outer region of the showerhead and off-centre from an axis of rotation. The plasma generators generate plasma in line of sight of the susceptor and the plasma inlets have openings that are larger than openings of the gas inlets. The gas inlets are configured such that a combination of all of the spatial distributions of gas from the gas inlets provides a uniform distribution of gas density on the surface of a susceptor between a central region and an outer region of the susceptor, for a full rotation of the susceptor.

Abstract: An apparatus and method for forming a thin film on a substrate by RPCVD which provides for very low levels of carbon and oxygen impurities and includes the steps of introducing a Group VA plasma into a first deposition zone of a growth chamber, introducing a Group IIIA reagent into a second deposition zone of the growth chamber which is separate from the first deposition zone and introducing an amount of an additional reagent selected from the group consisting of ammonia, hydrazine, di-methyl hydrazine and a hydrogen plasma through an additional reagent inlet into the second deposition zone such that the additional reagent and the Group IIIA reagent mix prior to deposition.

Abstract: An apparatus and method for forming a thin film on a substrate by RPCVD which provides for very low levels of carbon and oxygen impurities and includes the steps of introducing a Group VA plasma into a first deposition zone of a growth chamber, introducing a Group IIIA reagent into a second deposition zone of the growth chamber which is separate from the first deposition zone and introducing an amount of an additional reagent selected from the group consisting of ammonia, hydrazine, di-methyl hydrazine and a hydrogen plasma through an additional reagent inlet into the second deposition zone such that the additional reagent and the Group IIIA reagent mix prior to deposition.

Abstract: RPCVD apparatus for forming a film is disclosed including a showerhead having at least one gas chamber, one or more plasma inlets to deliver plasma from one or more plasma generators into a reaction chamber; and a plurality of gas inlets to deliver gas from at least one gas chamber into the reaction chamber. At least one of the plasma inlets is located at a position that is between a central region and an outer region of the showerhead and off-centre from an axis of rotation. The plasma generators generate plasma in line of sight of the susceptor and the plasma inlets have openings that are larger than openings of the gas inlets. The gas inlets are configured such that a combination of all of the spatial distributions of gas from the gas inlets provides a uniform distribution of gas density on the surface of a susceptor between a central region and an outer region of the susceptor, for a full rotation of the susceptor.

Abstract: Methods for fabricating semiconductor devices incorporating an activated p-(Al,In)GaN layer include exposing a p-(Al,In)GaN layer to a gaseous composition of H2 and/or NH3 under conditions that would otherwise passivate the p-(Al,In)GaN layer. The methods do not include subjecting the p-(Al,In)GaN layer to a separate activation step in a low hydrogen or hydrogen-free environment. The methods can be used to fabricate buried activated n/p-(Al,In)GaN tunnel junctions, which can be incorporated into electronic devices.

Abstract: An apparatus and method for forming a thin film on a substrate by RPCVD which provides for very low levels of carbon and oxygen impurities and includes the steps of introducing a Group VA plasma into a first deposition zone of a growth chamber, introducing a Group IIIA reagent into a second deposition zone of the growth chamber which is separate from the first deposition zone and introducing an amount of an additional reagent selected from the group consisting of ammonia, hydrazine, di-methyl hydrazine and a hydrogen plasma through an additional reagent inlet into the second deposition zone such that the additional reagent and the Group IIIA reagent mix prior to deposition.

Abstract: A plasma generator is described which employs a partial PBN liner not only to minimise the loss of energetic gas species during film formation but also to reduce boron impurity levels introduced into the growing film relative to the use of a complete PBN liner. The use of such a plasma generator in a film forming apparatus and method of forming a film is also described.

Abstract: Methods for fabricating semiconductor devices incorporating an activated p-(Al,In)GaN layer include exposing a p-(Al,In)GaN layer to a gaseous composition of H2 and/or NH3 under conditions that would otherwise passivate the p-(Al,In)GaN layer. The methods do not include subjecting the p-(Al,In)GaN layer to a separate activation step in a low hydrogen or hydrogen-free environment. The methods can be used to fabricate buried activated n/p-(Al,In)GaN tunnel junctions, which can be incorporated into electronic devices.

Abstract: Methods for fabricating semiconductor devices incorporating an activated p-(Al,In)GaN layer include exposing a p-(Al,In)GaN layer to a gaseous composition of H2 and/or NH3 under conditions that would otherwise passivate the p-(Al,In)GaN layer. The methods do not include subjecting the p-(Al,In)GaN layer to a separate activation step in a low hydrogen or hydrogen-free environment. The methods can be used to fabricate buried activated n/p-(Al,In)GaN tunnel junctions, which can be incorporated into electronic devices.

Abstract: Methods for fabricating semiconductor devices incorporating an activated p-(Al,In)GaN layer include exposing a p-(Al,In)GaN layer to a gaseous composition of H2 and/or NH3 under conditions that would otherwise passivate the p-(Al,In)GaN layer. The methods do not include subjecting the p-(Al,In)GaN layer to a separate activation step in a low hydrogen or hydrogen-free environment. The methods can be used to fabricate buried activated n/p-(Al,In)GaN tunnel junctions, which can be incorporated into electronic devices.

Abstract: Methods for fabricating semiconductor devices incorporating an activated p-(Al,In)GaN layer include exposing a p-(Al,In)GaN layer to a gaseous composition of H2 and/or NH3 under conditions that would otherwise passivate the p-(Al,In)GaN layer. The methods do not include subjecting the p-(Al,In)GaN layer to a separate activation step in a low hydrogen or hydrogen-free environment. The methods can be used to fabricate buried activated n/p-(Al,In)GaN tunnel junctions, which can be incorporated into electronic devices.

Abstract: Methods for fabricating semiconductor devices incorporating an activated p-(Al,In)GaN layer include exposing a p-(Al,In)GaN layer to a gaseous composition of H2 and/or NH3 under conditions that would otherwise passivate the p-(Al,In)GaN layer. The methods do not include subjecting the p-(Al,In)GaN layer to a separate activation step in a low hydrogen or hydrogen-free environment. The methods can be used to fabricate buried activated n/p-(Al,In)GaN tunnel junctions, which can be incorporated into electronic devices.

Abstract: Methods for fabricating semiconductor devices incorporating an activated p-(Al,In)GaN layer include exposing a p-(Al,In)GaN layer to a gaseous composition of H2 and/or NH3 under conditions that would otherwise passivate the p-(Al,In)GaN layer. The methods do not include subjecting the p-(Al,In)GaN layer to a separate activation step in a low hydrogen or hydrogen-free environment. The methods can be used to fabricate buried activated n/p-(Al,In)GaN tunnel junctions, which can be incorporated into electronic devices.

Abstract: Methods for fabricating semiconductor devices incorporating an activated p-(Al,In)GaN layer include exposing a p-(Al,In)GaN layer to a gaseous composition of H2 and/or NH3 under conditions that would otherwise passivate the p-(Al,In)GaN layer. The methods do not include subjecting the p-(Al,In)GaN layer to a separate activation step in a low hydrogen or hydrogen-free environment. The methods can be used to fabricate buried activated n/p-(Al,In)GaN tunnel junctions, which can be incorporated into electronic devices.

Abstract: A plasma generator is described which employs a partial PBN liner not only to minimise the loss of energetic gas species during film formation but also to reduce boron impurity levels introduced into the growing film relative to the use of a complete PBN liner. The use of such a plasma generator in a film forming apparatus and method of forming a film is also described.

Abstract: An apparatus and method for forming a thin film on a substrate by RPCVD which provides for very low levels of carbon and oxygen impurities and includes the steps of introducing a Group VA plasma into a first deposition zone of a growth chamber, introducing a Group IIIA reagent into a second deposition zone of the growth chamber which is separate from the first deposition zone and introducing an amount of an additional reagent selected from the group consisting of ammonia, hydrazine, di-methyl hydrazine and a hydrogen plasma through an additional reagent inlet into the second deposition zone such that the additional reagent and the Group IIIA reagent mix prior to deposition.

Abstract: A rotary gasoline engine has two sets of pistons, which move reciprocally. The reciprocal output of said pistons is coupled to an undulating ramp, which converts the reciprocal motion to rotary motion. The engine casing has a hollow center though which no shaft runs. Dual rotary outputs are provided, one through a rotatable output block at the top end of the casing, the other through a rotatable block at the bottom end of the casing in response to the reciprocal motion of the pistons.

Abstract: The present invention relates to the design and manufacture of microstructured optical fibres. The invention has particular application in the manufacture of microstructured optical fibres for imaging purposes such as, for example, endoscopy, ear-implants, and chip-to-chip interconnects. A first aspect of the invention provides a method of producing a microstructured optical fibre from a preform, said method including the steps of: creating zones of relatively high refractive index at predetermined locations in said preform, said zones substantially surrounded by material of relatively low refractive index to create an array of light guiding cores, and subsequently drawing said preform to create a length of said microstructured optical fibre.

Abstract: A rotary gasoline engine has two sets of pistons, which move reciprocally. The reciprocal output of said pistons is coupled to an undulating ramp, which converts the reciprocal motion to rotary motion. The engine casing has a hollow center though which no shaft runs. Dual rotary outputs are provided, one through a rotatable output block at the top end of the casing, the other through a rotatable block at the bottom end of the casing in response to the reciprocal motion of the pistons.

Abstract: A distribution network for distributing a clock signal comprising a sequence of counter signals, the network comprising a plurality of delivery points for facilitating simultaneous detection of different counter signals to provide timing information, wherein the clock signal comprises a modulated carrier, whereby the sequence of counter signals is in the form of an envelope of the carrier.