晶振工作原理及制程

《晶振工作原理及制程》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、Nov.20,2001IntroductionofQuartzCrystalLindaLin/FAEDepartmentContentsCharacteristicofQuartzMaterialCharacteristicsofCrystalUnitsChoosetheRightCrystalUnitCharacteristicsofQuartzMaterialQuartzMaterialPiezoElectricityWhyisAT-CutFrequencyvs.ThicknessLapping&EtchingQuartzMaterial(1)材料成份：二氧

2、化矽SiO2材料組成：正六方晶系TRIGONAL-DIGONALCLASS：32材料特性：熔點1,750℃@1atmα-β相變點537℃@1atm硬度~7.2莫氏硬度@25℃密度2,648Kg/M3@25℃壓電特性Y軸：機械軸MECHANICALAXIS光雙折性Z軸：光學軸OPTICALAXISQuartzMaterial(2)QuartzMaterial(3)SYNTHETICQUARTZCRYSTALAUTOCLAVEHYDROTHERMALMETHODRAWMATERIAL：SilicaHIGHPRESSURE：800to2,000atmospheresH

3、IGHTEMPERATURE：~400℃HIGHTEMP.STABILITY：±0.2℃LONGGROWTHTIME：1~6MonthHIGHPURITY：Infra-RedAbsorption(IRA)：3585CM-1PiezoElectricity(1)Thepositiveelectric-fieldisinducedwhenthemechanicforcepulltheOxygenatomoutoforiginalposition.Thenegativeelectric-fieldisinducedwhenthemechanicforcepushthe

4、Oxygenatomtowardcenterposition.TheSiO2isalwaysinthestaticstateofelectricneutrial.PiezoElectricity(2)Whenaelectricfieldapplied,theinducedelectricfiledisgeneratedandforcetheOxygenatommoveoutward.TheSiO2isalwaysinthestaticstateofelectricneutral.Whenaelectricfieldapplied,theinducedelectr

5、icfiledisgeneratedandforcetheOxygenatommovecloser.振動模式長度彎曲振動Length-widthflexure伸縮振動Extensionalflexure輪廓振動Faceshearflexure厚度振動Thicknessshearflexure基本波：Fundamental3倍頻：3rdovertone5倍頻：5thovertoneWhyisAT-Cut(1)WhyisAT-Cut(2)FundamentalMovement3rdOvertoneMovement20Mhz60Mhz0.082mm0.082mm+-+

6、-WhyisAT-Cut(2)LowFrequencyCT+380DT-520ET+660FT-570HighFrequencyAT+35015’BT-490各種切割角度/溫度之關係WhyisAT-Cut(3)AT切割角度/溫度之關係WhyisAT-Cut(4)Frequencyvs.ThicknessAT-CutCrystalF(MHz)=1670T(um)F(kHz)=1670T(mm)orFrequency14.318MHz20.000MHz26.973MHz35.328MHzThickness0.116mm0.083mm0.062mm0.047mmLap

7、ingMachinismLaping&Etching(1)SurfaceTreatment&EtchingLaping&Etching(2)AVG.sizeRoughnessInter-Crackumumum#50025622#80014310#100011.52.58#20006.51.13.5#30004.00.82.6#40002.70.51.3#60002.00.30.8#100000.600.080.05Note:Theroughnessandinter-crackdataaredependetonthequartzmaterialandthetype

8、ofabbresive.