Abstract: A method for producing high-purity, large-volume monocrystals that are especially radiation-resistant and have low intrinsic birefringence. From a melt of crystalline raw material, with controlled cooling and solidification, a crystal is generated. As the crystalline raw material, shards and/or waste from already-grown crystals is used, and the re-used raw material 1) upon visual observation in daylight has no color; and 2) upon illumination with a white-light lamp in a darkroom a) has no or at maximum a just barely perceivable reddish and/or bluish fluorescence; and b) has no or at maximum a just barely perceivable diffuse scattering; and c) has no or only slight discrete scattering of at maximum two visually perceivable scattering centers per dm3. In this way, crystals can be obtained which after tempering have a BSDF value of <7×10?7, an RMS homogeneity after the subtraction of 36 Zernike coefficients of <15×10?8, an SDR-RMS value in the 111 direction of <0.2 nm/cm.

Abstract: The upper block 12 contacts the bearing block 20, and the bearing block 20 is coupled to the upper plate 21. The upper block 12 has a protruding part 22 on the upper surface that is worked into a convex surface with a radius of R1, and the bearing block 20 has a recessed part 23 in the undersurface that is worked into a concave surface with a radius of R2 (R2>R1). As a result of such a construction being used, the pressing surface of the upper pressing plate 15 always conforms to the surface of the quartz crystal substrate 11 during pressing, so that a uniform load is applied to the quartz crystal substrate 11. As a result, the surface of the quartz crystal can be uniformly pressed in the hot pressing method.

Abstract: Rectangular protruding parts 2 are formed on the surface of one side of a quartz crystal substrate 1; these protruding parts 2 are formed as aggregates of rectangular protruding parts 4 of an even finer pattern. Recessed parts 5 which are lower than the surfaces of the protruding parts 4 are formed between the protruding parts 4; however, the width of these recessed parts 5 is narrow, so that when the protruding parts 4 are viewed on the macroscopic scale, numerous protruding parts 4 are aggregated, and appear to form single protruding parts 2. Such a quartz crystal substrate 1 is clamped between heater blocks from above and below, and the temperature of the quartz crystal substrate is elevated. At the point in time at which this temperature reaches a desired temperature, the substrate 1 is pressed by means of a press. Consequently, stress acts only on the portions corresponding to the protruding parts 4, so that the crystal axis components are inverted only in these portions.

Abstract: A single crystal of quartz thin film and a production method therefor are provided. A method for producing a quartz epitaxial thin film comprises the steps of vaporizing a silicon alkoxide as a silicon source under atmospheric pressure to introduce the silicon alkoxide to a substrate with hydrogen chloride as a reaction promoter, and reacting ethyl silicate with oxygen to deposit a quartz on the substrate. The single crystal of quartz thin film has excellent crystalinity, and optical properties.

Abstract: A crystal oscillator and method for manufacturing same including excitation electrode portions formed upon a crystal substrate and thus forming an excitation portion of the area defined between the electrode portions. Axis inversion portions possess an electrical axis (−X) opposite to the electrical axis (X) of the excitation portion, these axis inversion portions being formed within the crystal substrate at a position other than that of the excitation portion. A stable resonance frequency and filter frequency can be obtained even under conditions of ambient temperature fluctuation, by means of a relatively simple temperature compensation circuit, wherein handling is easy and no complicated adjustment is necessary, and low costs can be realized.

Abstract: A single crystal quartz thin film having a thickness of 5 nm to 50 .mu.m can be prepared by forming the thin film on a single crystal substrate by a sol-gel process and peeling the thin film from the substrate. The present invention can provide the single crystal quartz thin film at a low price without a large and complex apparatus.

Abstract: ST-cut and AT-cut quartz seed bodies (18,40) for quartz crystal synthesis and method (100) for making the same are disclosed. An extended quartz seed body (18) having an angle of about 42.75.degree. rotated about a X axis (20) from a +Z axis (22) to a -Y axis (24) and defining a ST-cut is provided and a quartz crystal bar (32) is grown thereupon. Analogously, an extended quartz seed body (40) having an angle of about 35.25.degree. rotated about a X axis (20) from a +Z axis (22) to a -Y axis (24) and defining an AT-cut is provided and a quartz crystal bar (48) is grown thereupon. In each case, the subsequent quartz crystal bar (32,48) may be wafered parallel to the seed body (18,40) thereby; reducing waste (68), recovering the seed body (18,40) for reuse, producing wafers (70) without intervening seed portions, and increasing factory capacity.

Abstract: Provided are high-purity quartz glass having a high purity, in particular, with little zirconium (Zr) and manufactured at low costs from natural quartz as the starting material and a method for the preparation thereof.

Abstract: A quartz crucible for use in the preparation of silicon crystals substantially free from crystal void defects and a process for its preparation are disclosed. The crucible is prepared by introducing quartz powder into a rotating mould in an atmosphere containing less than about 0.5% insoluble gases such as argon. The quartz powder accumulates along the inner surface of the mould, and is subsequently heated to fuse the quartz powder to produce the crucible. The gases contained in the bubbles in the resulting crucible are comprised of less than about 0.5% insoluble gases.

Abstract: ST-cut and AT-cut quartz seed bodies (18,40) for quartz crystal synthesis and method for making the same are disclosed. An extended quartz seed body (18) having an angle of about 42.75.degree. rotated about a X axis (20) from a +Z axis (22) to a -Y axis (24) and defining a ST-cut is provided and a quartz crystal bar (32) is grown thereupon. Analogously, an extended quartz seed body (40) having an angle of about 35.25.degree. rotated about a X axis (20) from a +Z axis (22) to a -Y axis (24) and defining an AT-cut is provided and a quartz crystal bar (48) is grown thereupon. In each case, the subsequent quartz crystal bar (32,48) may be wafered parallel to the seed body (18,40) thereby; reducing waste (68), recovering the seed body (18,40) for reuse, producing wafers (70) without intervening seed portions, and increasing factory capacity.

Abstract: A method of obtaining a crystal by crystal growth in the liquid phase from a seed in the form of a plate taken from a primary crystal, which method comprises at least two steps constituted firstly by forming first crystal growth to obtain a secondary crystal from a first seed taken from said primary crystal in a first growth zone, and secondly in performing second crystal growth from a second seed taken from said secondary crystal in a second growth zone, said first and second seeds being selected so that few of the dislocations that they contain propagate respectively into the second zone of the secondary crystal or into the first growth zone of the resulting crystal. According to the invention said first and second crystal growth steps are performed in different growth directions. Application to monocrystals of quartz, or of materials that are isomorphs of quartz, such as berlinite, and that are intended for use in making electronic components, in particular oscillators and filters.

Abstract: An apparatus (10) and method are provided for directly viewing, through a viewport assembly (26), the process for forming a layer of mercury cadmium telluride of a predetermined composition on a surface of a wafer (not shown). According to the invention, a molten melt (20) comprising mercury, cadmium and tellurium is provided in a vertically oriented crystal growth chamber (14), which, in turn, is housed in a reactor tube (12). A wafer (not shown) is contacted with the crystal growth melt while cooling the melt below its liquidus temperature at a predetermined rate sufficient to cause a crystal growth layer of mercury cadmium telluride to form on the wafer (not shown). Viewports (26, 48) located approximately radially adjacent to the melt (22) provide direct see through capability to visually monitor the crystal growth process.