Glass Wafers

HPFS® Fused Silica Standard Grade Wafers

Material Description

HPFS High Purity Fused Silica Standard Grade 7980 glass wafers are a high purity synthetic amorphous silicon dioxide manufactured by flame hydrolysis. The noncrystalline, colorless, silica glass combines a very low thermal expansion coefficient with excellent optical qualities and exceptional transmittance in ultraviolet. Fused Silica is available in various grades for different applications.

Glass Wafer Options

Coresix produces HPFS® Fused Silica Standard Grade Wafers to all SEMI Standards, including dimensional, flat and notch specifications. Additionally, we offer custom specifications designed to your unique needs, such as alignment marks, holes, pockets, edge profile, thickness, flatness, surface quality, cleanliness or other details critical to your application.

Wafer Specifications

Attribute Standard Best
Grade 0F 7980 0AA -  5G
Diameter 50.8, 76.2, 100, 150, 200, 300 Custom Diameters
Diameter Tolerance +/- 200μm +/- 50 μm
Thickness .5, .7, 1.0, 2.0 Custom .45mm - 12.0mm
Thickness Tolerance +/- 50μm +/- 5 μm
Thickness Variation (TTV) <10μm <1μm
Scratch and Dig 60/40 5/2
Roughnes (RMS) <7Å <3Å
Warp <100μm <20μm
Flatness λ per Inch TIR λ/10 per Inch TIR

Electrical Properties

Log10 Volume Resistivity (250°C, 482°F) 11.8 ohm*cm

Mechanical Properties

Density (25°C) 2.20 g/cm3
Elastic (Young's) Modulus 73 GPa
Shear Modulus (25°C) 31GPa
Modulus of Rupture, abraded 52.4 MPa
Bulk Modulus 35.9 GPa
Knoop Hardness (100g load) 522 kg/mm2
Poisson's Ratio 0.16
Tensile Strength 54 MPa
Compressive Strength 1.14 GPa

Thermal Properties

Softening Point* 1585 °C
Annealing Point* 1042 °C
Strain Point* 893 °C
Specific Heat 0.770 J/(g K)
Thermal Conductivity 1.38 W/mk
Thermal Diffusivity 0.0075 cm2/s
Thermal Expansion **  (ppm/C)  
5°C to 35° C 50.52 x 10-6
0°C to 200°C 0.57 x 10-6
-100°C to +200°C 0.48 x 10-6
ASTM Procedures - *C-598, **E-228  

Optical Properties

Abbe Constraints Ve 67.6 Vd 67.8
Stress Coefficient 35.0 nm/cm MPa  
Refractive Index Conditions: 22  ̊C, 760 mm Hg, N2 Refractive Index 2n Thermal Coefficient ∆n/∆T3 [ppm/C]
@435.957ng 1.466691 10.6
@587.725nd 1.458461 10.1
@656.454nc 1.456364 9.9
HPFS Fused Silica Standard Grade Wafers Optical Transmission