Patent ID: 6469423
Filing Date: 2002-10-22
Classification: H03H

Abstract:
A rectangular AT-cut quartz element, said rectangular AT-cut quartz element being cut from a single-crystal quartz having the XYâ€²Zâ€²-axis system obtained by rotating the XYZ-orthogonal coordinate system about its X-axis wherein the X-axis is defined by the electrical axis, the Y-axis is defined by a mechanical-axis, and the Z-axis is defined by an optical axis wherein, said rectangular AT-cut quartz element has a thickness t in a direction along said Yâ€²-axis and a width w in a direction along said Zâ€²-axis, and wherein said rectangular AT-cut quartz element has a surface subjected to an etching process, and a maximum height Rmax of a surface roughness is in a range from above 0.2 &mgr;m to 0.7 &mgr;m.