Materials | both Pure Z and Y bar available | Synthetic Q Value | min 1.8 , 2.4 to 3.0 mil IEC |
Etch Channel Density | max 15/cm2 max100/cm2; max300/cm2 | Stress | No dark or discolored visible in polarized light |
Surface Finishing | #1000, #2000, #3000 , #4000, and Polished std | Angle Tolerance | ZZ': +/-15" +/-30", +/-1' +/-2' |
XX' | +/-15 , +/-30' | Cut Type | AT. BT. IT ,SC,....,etc. |
Frequency | 1Mhz up to 50 Mhz for AT-fundamental | Size for Round Blank | from 3.0 to 15.0 mm dia (with flat) |
Size for Wafer | 2.0x8.0 (mm)~ 16x16(mm) | SMD Type | 2.5x3.0 above at Customer option |
Flat | as requested the flat shall be perpendicular to X axis within +/- 10 deg |
Specifications for 3”/4”/5”/6” Quartz Wafers
Specifications for 3”/4”/5”/6” Quartz Wafers | ||||
Wafer Size | 3” | 4” | 5” | 6” |
Diameter(mm) | 76.2 | 100 | 125 | 150 |
Tolerance (±mm) | 0.25 | 0.5 | 0.5 | 0.5 |
Primary Reference Flat (mm) | 22mm or customized | 32.5mm or customized | 42.5mm or customized | 57.5mm or customized |
LTV (5x5mm) (μm) | <2 | <2 | <2 | <2 |
TTV (μm) | <8 | <10 | <15 | <20 |
Bow (μm) | ±20 | ±25 | ±40 | ±40 |
Warp(μm) | ≤30 | ≤40 | ≤50 | ≤50 |
PLTV (%) (5x5mm) | ≥90% | ≥90% | ≥90% | ≥90% |
Cutting Angle | AT36/ST42.75/X/Y/Z etc | |||
Orientation Flat | All available | |||
Surface Type | Single side polished/Double sides polished | |||
Polished Side Ra (nm) | ≤1 | |||
Back Side Criteria (μm) | General is 0.2-0.5 or as customized | |||
Edge Rounding | Compliant with SEMI M1.2 Standard/refer to IEC62276 | |||
Appearance | Contamination: None | |||
Particles Φ>0.3μm: ≤30 | ||||
Saw Marks, striations: None | ||||
Scratch: None | ||||
Cracks, crowsfeet, Saw marks, strains: None |
Basic Properties:
1. Physical Properties of Synthetic Crystal Quartz
Density(g/cm3) | 2.65 | Melting Point(°C) | 1467 |
Thermal Conductivity, W/(m x K) (T = 25°C) |
10.7 (parallel to axis Z) 6.2 (perpendicular to axis Z) |
Thermal Conductivity, W/(m x K) (T = 25°C) |
7.1 õ 10-6 (parallel to axis Z) 13.2 õ 10-6 (perpendicular to axis Z) |
Hardness (Mohs) | 7 | Specific Heat Capacity, J/(kg x K) (T = 25°C) |
710 |
Specific Heat Capacity, J/(kg x K) (T = 25°C) |
4.34 (parallel to axis Z) 4.27 (perpendicular to axis Z) |
Young's Modulus (E), GPa | 4.34 (parallel to axis Z) 4.27 (perpendicular to axis Z) |
Shear Modulus (G), GPa | 31.14 | Bulk Modulus (K), GPa | 36.4 |
Chemical Stability | insoluble in water | Elastic Coefficients | C11=87 C12=7 C44=58 C13=13 C14=18 C33=106 |
2. Synthetic Crystal Quartz Refractive Index vs Wavelength
Synthetic Crystal Quartz Refractive Index vs Wavelength | ||||||||
λ(μm) | n0 | ne | λ(μm) | n0 | ne | λ(μm) | n0 | ne |
0.185 | 1.676 | 1.690 | 0.243 | 1.605 | 1.617 | 0.589 | 1.544 | 1.553 |
0.194 | 1.660 | 1.673 | 0.263 | 1.593 | 1.604 | 1.083 | 1.534 | 1.543 |
0.204 | 1.643 | 1.656 | 0.291 | 1.581 | 1.591 | 1.800 | 1.524 | 1.532 |
0.219 | 1.625 | 1.637 | 0.340 | 1.567 | 1.577 | 2.500 | 1.512 | 1.520 |
0.231 | 1.614 | 1.626 | 0.405 | 1.557 | 1.567 | 3.000 | 1.500 | 1.507 |
Application Notes:
1. Materials
This material consists of single-crystal right-handed a-quartz artificially grown bars which is intended for use in fabrication of piezoelectric for such as timing freq control and frequency selection under hydro-thermal condition on a seed with its length along the Y axis. This cultured quartz crystal shall have nominal Q specification defined by followed grade: Grade Q-VALUE : Specification of the synthetic quartz crystal.
Specification of Quartz Crystals | ||||
Infrared Absorption α 3585 | ≤ 0.024 | ≤ 0.024 | ≤ 0.05 | ≤ 0.05 |
Q x106 | 3.0 | 3.0 | 2.4 | 2.4 |
Inclusions Density | I | I | I | I or II |
Etch Channel Density (strips/cm2 ) | ≤10 | ≤30 | ≤100 | ≤100 |
2. Quality Evaluation of Synthetic Quartz Crystal
2.1 The amount of crystal defect and impurity in synthetic quartz crystal depends on growth rate, mineralizer and raw material. The growth rate affects greatly to the important properties such as infra-red absorption coefficient α, which correlates to Q value, and frequency –temperature characteristics. The larger growth rate causes increase in α, decrease in Q value, and dispersion in frequency-temperature characteristics.
2.2 The quality index of synthetic quartz crystal was originally a Q value, and a 5 MHz quartz crystal unit operated in 5th overtone mode was used to obtain the Q value. But it required laborious work to fabricate the 5 MHz crystal unit, so the index had been changed to the coefficient α instead of the Q value.
3. Standard Specification for Synthetic Quartz Crystal
3.1 Twinning: There shall be no electrical or optical twinning in the usable region.
3.2 Strain: There shall be no strain contained both inside and surface of seed crystal as well as in a grown quartz crystal.
3.3 Cracks and fractures: There shall be no cracks, chippings or fractures in the usable region.
3.4 Inclusion density: The specification is in accordance with the IEC 60758.
Size Range (μm) Grade | Q’ty Per(cm3) | |||
10 to 30 | 30 to 70 | 70 to 100 | >100 | |
Ia | 2 | 1 | 0 | 0 |
Ib | 3 | 2 | 1 | 1 |
I | 6 | 5 | 2 | 2 |
II | 9 | 5 | 4 | 3 |
III | 12 | 8 | 6 | 4 |
3.5 Infra-red quality indication: The specification is in accordance with the IEC 60758.
Grade | Max. α3585 | Estimated Q Values (x 106) |
A | 0.015 | 3.8 |
A | 0.024 | 3.0 |
B | 0.050 | 2.4 |
C | 0.069 | 1.8 |
D | 0.100 | 1.4 |
3.6 Etch channel density: The specification is in accordance with the IEC 60758.
Grade | Max. Number Per(cm3) |
1 | 10 |
2 | 30 |
3 | 100 |
4 | 300 |
5 | 600 |
4. Specification for Lumbered Quartz Crystal
4.1 Angles:
4.1.1 angle of X-surface around Y-axis: 00°00’±15’
4.1.2 Rotation angle of X-surface around Z-axis: 00°00’±15’
4.2 Dimensional tolerance:
4.2.1 along X or Z axis:±0.1 mm
4.2.2 along Y axis:±10 mm
4.3 Surface roughness: as customized ,lapped and polished are both available.
Quartz crystal, chemical composition SiO2, and alpha quartz are the main ones used for SAW devices. Its melting point is 1750℃. The density is 2.65×103 kg/m3, and the Mohs hardness is 7. SAW-grade Quartz crystal wafers are favorable for Surface Acoustic Wave (SAW) application with remarkable piezoelectric properties. The thermal stability of quartz crystal is one of its most appealing attributes, its piezoelectric coefficient and dielectric coefficient remain almost unchanged at room temperature. In addition, other advantages of quartz crystal include high mechanical strength and quality factor, high rigidity, good dynamic characteristics, no pyroelectric and ferroelectric effect, good insulation, etc.
Quartz crystals are the most representative and common piezoelectric crystals among single crystals. The applications of piezoelectric quartz include resonators, high-frequency oscillators, and filters, and is widely integrated into navigation, remote control, telemetry, electronics, and electric equipment for automatic weapons, supersonic aircraft, missiles, nuclear weapons, electron microscopes, chronographs, etc.
Hangzhou Shalom EO offers Custom SAW grade quartz crystals and wafers, advanced facilities are equipped for crystal growth, wafer cutting, wafer lapping, wafer polishing, and wafer checking, and all finished products undergo Curie Temp testing and QC inspections. Quartz crystal ingots, crystal blanks, wafer blanks, and polished wafers are available upon customers' request.
Various Types of Quartz Crystal Orientation