Abstract:
The present invention relates to increasing the photosensitivity of optical fibers. One aspect of the present invention comprises a method for rapidly diffusing hydrogen or deuterium into an optical fiber from a gas mixture having a low total hydrogen content to generate changes in the refractive index of the optical fiber. The resulting photosensitive fiber may be used to create optical devices including Bragg gratings and Bragg grating-based devices.
Abstract:
The invention relates to a method for the production of opaque quartz glass wherein a blank is made from synthetic SiO2 crystals and heated to form a blank body made of opaque quartz glass at a given vitrification temperature. A method for the production of pure, opaque quartz glass is disclosed wherein said quartz glass has a homogeneous pore distribution and a high density, a high viscosity and a lower tendency to devitrify. According to the invention, the SiO2 crystals are formed from an at least partially porous agglomerate of SiO2 primary particles (21; 31) having a specific surface (according to BET) between 1.5 m /g and 40 m /g with a stamping density of at least 0.8 g/cm . SiO2 granulate (21; 31) suitable for use in performing the procedure is characterized in that it is composed of an at least partially porous agglomerate of SiO2 primary particles and has a specific surface (according to BET) between 1.5 m /g and 40 m /g in addition to a stamping density of at least 0.6 g/cm .
Abstract:
A composition represented by the formula Si1-xGexO2(1-y)N1.33y, wherein x is from about 0.05 to about 0.6 and y is from about 0.14 to about 0.74 exhibits properties highly suited for use in fabricating waveguides for liquid crystal based optical devices. In particular, the compositions have an index of refraction of from about 1.6 to about 1.8 for light at a wavelength of 1550 nm, and/or a coefficient of thermal expansion of from about 2.5 x 10-6°C-1 to about 5.0 x 10-6°C-1. The compositions also have inherently low hydrogen content, and a high hydrogen permeability which allows better hydrogen removal by thermal annealing to provide a material which exhibits low optical losses and better etching properties than alternative materials.
Abstract:
The invention starts from a known component of quartz glass for use in semiconductor manufacture, which component at least in a near-surface region shows a co-doping of a first dopant and of a second oxidic dopant, said second dopant containing one or more rare-earth metals in a concentration of 0.1-3% by wt. each (based on the total mass of SiO 2 and dopant). Starting from this, to provide a quartz glass component for use in semiconductor manufacture in an environment with etching action, which component is distinguished by both high purity and high resistance to dry etching and avoids known drawbacks caused by co-doping with aluminum oxide, it is suggested according to the invention that the first dopant should be nitrogen and that the mean content of metastable hydroxyl groups of the quartz glass is less than 30 wtppm.
Abstract:
Ein ideales Quarzglas für einen Wafer-Halter zum Einsatz in ätzend wirkender Umgebung zeichnet sich sowohl durch hohe Reinheit als auch durch eine hohe Trockenätzbeständigkeit aus. Um ein Quarzglas anzugeben, das diese Anforde rungen weitgehend erfüllt, wird erfindungsgemäß vorgeschlagen, dass das Quarz glas mindestens in einem oberflächennahen Bereich mit Stickstoff dotiert ist, einen mittleren Gehalt an metastabilen Hydroxylgruppen von weniger als 30 Gew.-ppm aufweist, und dass seine fiktive Temperatur unterhalb von 1250 °C und seine Vis kosität bei einer Temperatur von 1200°C mindestens 1013 dPas betragen. Ein wirtschaftliches Verfahren zur Herstellung eines derartigen Quarzglases umfasst folgende Verfahrensschritte: Erschmelzen eines SiO2-Rohstoffs zu einem Quarz- glas-Rohling, wobei der SiO2-Rohstoff oder der Quarzglas-Rohling einer Entwäs serungsmaßnahme unterzogen werden, ein Erhitzen des SiO2-Rohstoffs oder des Quarzglas-Rohlings auf eine Nitridierungstemperatur im Bereich zwischen 1050°C und 1850 °C unter einer Ammoniak enthaltenden Atmosphäre, eine Temperatur behandlung, mittels der das Quarzglas des Quarzglas-Rohlings auf eine fiktive Temperatur von 1250 °C oder weniger eingestellt wird, und eine Oberflächenbe handlung des Quarzglas-Rohlings unter Bildung des Quarzglas-Halters.
Abstract:
To provide quartz-type glass for a microlithographic projection exposure apparatus, which contains at least 51 mass% of SiO 2 and which further contains at least one member selected from the group consisting of lanthanum, aluminum, hafnium, nitrogen, scandium, yttrium and zirconium. It is a material which is useful for an illumination system for a microlithographic projection exposure apparatus or as a projection object lens and has a refractive index at 248 nm larger than 1.508 of quartz glass and a refractive index at 193 nm larger than 1.560 of quartz glass and which can be small-sized.
Abstract:
A composition represented by the formula Si>1-x x 2(1-y) 1.33y DEG C to about 5.0 x 10 DEG C . The compositions also have inherently low hydrogen content, and a high hydrogen permeability which allows better hydrogen removal by thermal annealing to provide a material which exhibits low optical losses and better etching properties than alternative materials.