97 results about "Fluoride crystals" patented technology

An exposure apparatus (PE1) and exposure method for use in photolithographically manufacturing devices such as semiconductor devices, image pickup devices, liquid crystal display devices and thin film magnetic heads. The apparatus is capable of transferring onto a substrate (W) the image of a pattern on a reticle (R) and includes a light source (2) capable of supplying an exposure energy beam (IL) with a wavelength under 200 nm, and an illumination optical system arranged to receive the exposure energy beam from said light source. The illumination optical system is designed to guide the exposure energy beam to the reticle. The apparatus also includes a projection optical system (PL) arranged between the reticle and the substrate. The projection optical system is capable of forming an image of the reticle pattern onto the substrate based on the exposure energy beam passing through the reticle. The projection optical system has a plurality of refractive optical members, wherein at least two such refractive optical members are arranged along an optical path of said exposure energy beam, and wherein each refractive optical member is made of at least two types of fluoride crystalline materials.

The invention discloses a rare earth doped glass frequency conversion luminous material and a preparation method thereof. The luminous material is formed by fluoride glass ceramics containing rare earth ions and silver nanoparticles. The preparation method comprises the steps of firstly preparing glass containing rare earth ions, secondly preparing the glass into the glass ceramics containing fluoride crystals through the heat treatment technology, and thirdly soaking the glass ceramics in a mixed salt melt containing silver nitrate to undergo ion exchange, thus obtaining the rare earth doped frequency conversion luminous material jointly enhanced by the silver nanoparticles and fluoride microcrystals. The obtained luminous material has the beneficial effects that the luminous material has good optical property and thermal stability; through irradiation of exciting light, by utilizing the local field enhancement effect of the silver nanoparticles, the rare earth ions in a low phonon energy environment created by the fluoride microcrystals achieve high frequency conversion luminous efficiency which can be maximally enhanced by 30 times, thus effectively making up for the problem of low rare earth ion doped glass frequency conversion luminous efficiency.

The invention is directed to a coated metal fluoride crystals that are resistant to laser-induced damage by a below 250 nm UV laser beam; methods of making such coated crystals, and the use of such coated crystals. The method includes the steps of providing an uncoated metal fluoride crystal of general formula MF₂, where M is beryllium, magnesium, calcium, strontium and barium, and mixtures thereof, and coating the uncoated metal fluoride crystal with a coating of a selected material to thereby form a coated metal material resistant to laser induced damage. Preferred coating materials include MgF₂, MgF₂ doped fused silica and fluorine doped fused silica.

A method of determining materials of lenses contained in an optical system of a projection exposure apparatus is described. First, for each lens of a plurality of the lenses, a susceptibility factor K_LT/LH is determined. This factor is a measure of the susceptibility of the respective lens to deteriorations caused by at least one of lifetime effects and lens heating effects. Then a birefringent fluoride crystal is selected as a material for each lens for which the susceptibility factor K_LT/LH is above a predetermined threshold. Theses lenses are assigned to a first set of lenses. For these lenses, measures are determined for reducing adverse effects caused by birefringence inherent to the fluoride crystals.

The invention relates to optical glass with low refraction and chromatic dispersion, belonging to the technical field of new materials. The invention mainly provides phosphate fluoride optical glass capable of substituting a fluoride crystal material. The optical glass with low refraction and chromatic dispersion comprises phosphorus pentoxide and fluoride as main components and is characterized by being prepared from the following compounds in percentage by weight: 4-38 percent of P2O5, 5-32 percent of AlF3, 0.5-28 percent of BaF2, 0.5-30 percent of SrF2, 0.5-28 percent of CaF2, 0-12 percent of MgF2, 0.1-6 percent of SnF4, 0-20 percent of Na3AlF6, 0-12 percent of YF3, 0-12 percent of LaF3, 0-6 percent of GdF3, 0-20 percent of LiF and 0-8 percent of KF which are total 100 percent. The optical glass with low refraction and chromatic dispersion has the friction rate of 1.39-1.51, an Abbe number (vd) of 74-99, has the advantages of low conversion temperature and melting temperature, good stability and suitable production and is manly suitable for manufacturing lens and prisms of optical instruments which have high-accuracy chromatic aberration and are represented by cameras and projectors.

The invention provides a crystal laser device side pumped by laser diode and employing a fluorinated lutetium-lithium crystal dual-doped with thulium and holmium, which is characterized by adopting laser diode array side pump; a laser resonance cavity consists of a back reflection mirror and a front reflection mirror between which Tm:Ho:LuLF crystal is disposed. The invention has compact structure, low pumping threshold value, large pulse energy and the laser output wavelength is approximately 2 mum m, and the pulse repetition frequency is adjustable, so that the invention has widely application prospect on the aspects of laser ranging, coherent Doppler wind-finding radar and so on.

In the present invention, a short-wavelength light-emitting element such as an ultraviolet light-emitting element or blue light-emitting element is arranged in a container which has a window with a window board formed of calcium fluoride crystals. According to the present invention, it is possible to obtain a reliable light-emitting element device. Fluoride crystals of the present invention are ones which contain either metal or metal halide, or both of them. In a production method of fluoride crystals in which the cavity of a crucible is filled with raw material powder and this crucible is heated in a vertical Bridgman furnace, a production method of fluoride crystals of the present invention is the one in which the shortest diameter of a cross section of the cavity of the crucible is small. In a crucible, whose cavity is filled with raw material powder, heated in a vertical Bridgman furnace to produce fluoride crystals, a crucible of the present invention is the one in which the shortest diameter of a section of the cavity is small.

The invention discloses a method for growing large-size fluoride crystals through a top seed crystal kyropoulos method. The method comprises the following steps: weighing and mixing fluoride crystals and deoxidant powder, and pressing a mixture to form a block; drying the pressed block; putting the block into a crucible, sequentially installing thermal field components and installing seed crystals; vacuumizing, and heating to smelt the material until observing that the block is molten; descending the seed crystals to contact with a melting liquid level so as to slightly melt the seed crystals, pulling seed crystal rods and growing the block on the seed crystals in a condensation manner; after finishing crystal seeding, entering a shouldering period at power reduction, maintaining the crystals rotating and keeping the crystal pulling speed in the period, gradually increasing the diameters of the crystals in an upward pulling process, and entering an isometrical growth period until the crystal growth is finished; and cooling and annealing after the crystal weight reaches the feed weight. The method is low in growth cost and short in growth period; the method is suitable for large-size fluoride crystals, and the fluoride crystals grow in a vacuum condition without oxygen impurities; and the growth process is visible and controllable, so that the crystal quality is improved.

A lasing apparatus includes a laser medium and a pump source. The laser medium includes one of a Holmium-doped fluoride crystal or a Holmium-doped fluorozirconate ZBLAN glass fiber. The pump source generates pulses that resonantly pump the laser medium such that the laser medium produces an output from the ⁵I₅ level to the ⁵I₇ level of Holmium. The pump source produces pulses having a duration that is at least as long as a storage time of the ⁵I₅ level of the laser medium. The pump source pumps the laser medium with signals having a wavelength shorter than 1.67 μm, with the laser medium producing an output having a wavelength of about 1.67 μm.

A numerical optimizing method serves to reduce harmful effects caused by intrinsic birefringence in lenses of a fluoride crystal material of cubic crystal structure in an objective, particularly a projection objective for a microlithography system. Under the optimizing method, an optimizing function which takes at least one birefringence-related image aberration into account is minimized. The birefringence-related image aberration is determined from a calculation for a light ray passing through the fluoride crystal lenses. To the extent that the birefringence-related image aberration is a function of parameters of the light ray, it depends only on geometric parameters of the light ray. The numerical optimizing method is used to produce objectives in which an optical retardation as well as an asymmetry of the optical retardation are corrected. The lenses are arranged in homogeneous groups, where each homogeneous group is corrected for the optical retardation asymmetry.

The invention provides carbon quantum dot composite nanoparticles, and a carbon quantum dot/fluoride composite material, a preparation method and applications thereof, wherein carbon quantum dots arecompounded into the interior of fluoride crystals in carbon quantum dot/fluoride composite nanoparticles, such that the carbon quantum dots can achieve the advantages of solid-state light emitting, notoxicity, high-temperature resistance, decomposition resistance and good stability, and can absorb UV and be converted into blue light required for plants. The invention further provides a one-step preparation scheme of the carbon quantum dot/fluoride composite nanoparticles, wherein the one-step preparation scheme has characteristics of simple process and low cost, and is suitable for industrialproduction. The invention further provides a carbon quantum dot/fluoride/polymer composite material, which compounds the carbon quantum dot/fluoride nanoparticles and a polymer material, has high transparency, and further has light conversion, toughening or anti-aging effect, wherein the preparation method is simple and easy-performing, can be used for the preparation of agricultural films or rubber products, and has good industrialization prospect.

The invention discloses a preparation method of Eu<3+> ion-doped gadolinium fluoride/sodium gadolinium fluoride crystal phase-controllable luminescent powder, relating to a preparation method of a rare earth doped luminescent material. In the method, Gd2O3 (99.99 percent), Eu2O3 (99.99 percent), analytically-pure sodium fluoride (NaF) and polyvinylpyrrolidone (PVPMw=58.000) are taken as raw materials. The method comprises the following steps: (1) preparing a rare earth composite nitrate (gadolinium nitrate and europium nitrate) mixed solution; (2) adding polyvinylpyrrolidone and sodium fluoride; (3) performing a hydrothermal reaction on the mixed solution under the condition of different temperatures and different time; (4) washing and drying to obtain a product. A preparation process adopted in the method is simple, the entire reaction is performed in an aqueous solution, an added polymer is environmental friendly, high practicability is realized, and the crystal phase of the product can be controlled effectively under the condition that a basic formula is not changed in order to further control the luminescent property of the luminescent powder. The method is wide in application prospect.

The invention relates to a device for simultaneously growing various CaF2 doped crystals and a preparation method based on the device. The device comprises a tray, a heat insulating barrel, an induction coil, a bottom heat insulating layer, a crucible, a growth mold unit, seed crystals and a seed crystal rod, the bottom heat insulating layer, the crucible, the growth mold unit, the seed crystals and the seed crystal rod are sequentially arranged in the heat insulating barrel from bottom to top, the seed crystals are fixed at the bottom end of the seed crystal rod and can be vertically and movably arranged right above the growth mold unit, a plurality of mutually parallel crucible partitions are arranged in the crucible, an inner cavity of the crucible is divided into a plurality of mutually independent crystal growth intervals by the crucible partitions, the crystal growth intervals are not mutually communicated, and the growth mold unit comprises a plurality of crystal growth molds in one-to-one correspondence to the crystal growth intervals. Compared with the prior art, the device is low in growth cost, short in growth cycle, applicable to a plurality of other fluoride crystals, the crystals with various doping concentrations simultaneously grow, growth is protected by inert gas, anaerobic impurities are omitted, growth processes are visible and controllable, and crystal quality is high.

An object of the present invention is to provide a production apparatus and method of a fluoride crystal, and a crucible for the growth capable of efficiently eliminating impurities and a scavenger remained in the crystal so as to produce a fluoride crystal with a high transmissivity. A crucible divided into a plurality to have multi-stages is used for refining a material in the material refining process by adding a scavenger in the material. Further, a degassing hole was provided to the side wall portion of the crucible. A crucible of the present invention has at least two degassing holes at the side wall portion. Further, a crucible of the present invention has a connecting hole at the center part of the bottom face with at least two degassing holes in the side wall portion.

The invention is directed to a method for processing and annealing metal fluoride single crystals. Among other steps, the method includes of removing the as-grown surfaces of the crystals after they emerge from the growth furnace, processing the surfaces in such way that all the crystal surfaces have the same thermal properties, and then placing the crystals in a secondary annealing furnace to further anneal the crystals to release the residual stresses resulting from the primary annealing process. The invention is suitable for metal fluoride crystals of general formula MF₂, where M is calcium, magnesium, barium and strontium, and mixtures thereof.