학술논문
High stability evacuated HF crystals
Document Type
Conference
Author
Source
Proceedings of the 2002 IEEE International Frequency Control Symposium and PDA Exhibition (Cat. No.02CH37234) Frequency control symposium Frequency Control Symposium and PDA Exhibition, 2002. IEEE International. :370-374 2002
Subject
Language
Abstract
This work is devoted to results of development of high frequency fundamental mode (HFF) crystal resonators fabricated with an inverted mesa-structure procedure and sealed in HC-45 holders with a high vacuum process. The paper deals with analysis of various resonator parameters. Essential advantages of the vacuum-sealed crystals over conventional ones were observed in long-term frequency stability (aging). About 9 months aging tests with HFF vacuum-sealed units operating at 103-156 MHz shown 0.5-1.0 ppm frequency drift for the first month and 2-3 ppm for the 8 months period at 85/spl deg/C.