IEC 60758 pdf download.Synthetic quartz crystal – Specifications and guidelines for use
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61 994 and the following apply. 3.1 hydrothermal crystal growth crystal growth in the presence of water, elevated temperatures and pressures by a crystal growth process believed to proceed geologically within the earth’s crust Note 1 to entry: The industrial synthetic quartz growth processes utilize alkaline water solutions confined within autoclaves at supercritical temperatures (330 °C to 400 °C) and pressures (700 to 2 000 atmospheres). Note 2 to entry: The autoclave is divided into two chambers: the dissolving chamber, containing raw quartz chips at the higher temperature; the growing chamber, containing cut seeds at the lower temperature (see 7.1 .2). 3.2 synthetic quartz crystal single crystal of α quartz grown by the hydrothermal method Note 1 to entry: Cultured quartz has the same meaning as synthetic quartz crystal. 3.3 as-grown synthetic quartz crystal state of synthetic quartz crystal prior to grinding or cutting 3.4 as-grown Y-bar crystals which are grown by using long stick seed in the Y-direction 3.5 as-grown Z-bar crystals which are grown by using Z-cut seed 3.6 synthetic quartz crystal batch synthetic quartz crystals grown at the same time in one autoclave 3.7 seed rectangular parallelepiped quartz plate or bar to be used as a nucleus for crystal growth 3.8 growth zones regions of a synthetic quartz crystal resulting from growth along different crystallographic directions SEE: Figure 2. 3.9 orientation of a synthetic quartz crystal orientation of the seed of a synthetic quartz crystal with respect to the orthogonal axes specified in 3.7 3.1 0 orthogonal axial system of α quartz crystal orthogonal axis system consisting of three axes with a mutually vertical X axis, Y axis and Z axis as illustrated in Figure 1 Note 1 to entry: The z-cut seed may be oriented at an angle of less than 20°to the Y-axis, in this case the axial system becomes X, Y’, Z’. 3.1 1 AT-cut plate rotated Y-cut crystal plate oriented at an angle of about +35° around the X-axis or about −3° from the z (minor rhombohedral)-face SEE: Figure 3 3.1 2 X-cut plate crystal plate perpendicular to the X-axis SEE: Figure 3b 3.1 3 Y-cut plate crystal plate perpendicular to the Y-axis SEE:Figure 3b 3.1 4 Z-cut plate crystal plate perpendicular to the Z-axis SEE:Figure 3b 3.1 5 z (minor rhombohedral)-cut plate crystal plate parallel to the z (minor rhombohedral)-face 3.1 6 dimensions dimensions pertaining to growth on Z-cut seed rotated less than 20°from the Y-axis 3.1 7 effective Z-dimension as-grown effective Z dimension defined as the minimum measure in the Z or Z’ direction in usable Y or Y’ area of an as-grown crystal and described by Z eff SEE: Figure 2 3.1 8 minimum Z-dimension minimum distance from seed surface to Z-surface described by Z min SEE: Figure 2d 3.1 9 inclusions any foreign material within a synthetic quartz crystal, visible by examination of scattered light from a bright source with the crystal immersed in a refractive index-matching liquid Note 1 to entry: A particularly common inclusion is mainly the minerals called acmite and emeleusite. 3.20 seed veil array of inclusions or voids at the surface of the seed upon which a crystal has been grown 3.21 etch channel roughly cylindrical void that is present along the dislocation line after etching a quartz crystal 3.22 dopant additive used in the growth process which may change the crystal habit, chemical composition, physical or electrical properties of the synthetic quartz batch 3.23 pre-dimensioned bar bar whose as-grown dimensions have been altered by sawing, grinding, lapping, etc., to meet a particular dimensional requirement 3.24 impurity concentration concentration of impurities relative to silicon atoms 3.25 dislocations linear defects in the crystal due to misplaced planes of atoms 3.26 autoclave vessel for the high-pressure and high-temperature condition required for growth of a synthetic quartz crystal
IEC 60758 pdf download
