Fused Silica Spherical Powder (SiO₂)

Spherical fused silica across a fine grade ladder, the standard EMC filler for semiconductor encapsulation and silicone rubber filler. Small quantities, prototypes and custom made-to-order specifications are welcome.

Request a Quote Request Custom Specification

100nm–5µm grade ladderParticle Size Range

≥98–99%Purity Grade

Custom Made-to-OrderGrade & Quantity

WorldwideExport Shipping

Fused Silica Spherical Powder — Grades & Specifications

Spherical fused silica across a fine grade ladder, the standard EMC filler for semiconductor encapsulation and silicone rubber filler. The options below are typical; specify your target values in the request form and we will confirm availability, lead time and pricing.

Material	Fused Silica Spherical Powder
Chemical formula	SiO₂
CAS number	60676-86-0
Particle size	100nm–5µm grade ladder (fine sub-micron grades: 100nm, 0.3µm, 0.7µm; coarser 1–5µm+ grades also available)
Purity	≥98–99%
Morphology	Spherical
Appearance	White powder
Typical applications	Semiconductor EMC filler, Silicone rubber filler, Coatings & composites, Electronic packaging

Applications by Industry

Semiconductor EMC fillerEpoxy molding compound filler for chip encapsulation.

Silicone rubber fillerFunctional filler for silicone formulations.

Coatings & compositesLow-CTE functional filler.

Electronic packagingUnderfill and encapsulant formulations.

Particle Size & Mesh Conversion

Fused silica spherical powder is supplied across grades from 100 nm up to several microns. The finest grades (100 nm, 0.3 µm, 0.7 µm) are sub-micron and fall below the resolution of any US mesh/sieve number — even the finest standard sieve (12000 mesh) only resolves to 1 µm (1,000 nm). These fine grades are specified directly in nanometers/microns rather than by mesh; please state your target grade in the request form. Coarser grades (roughly 1 µm and up) can be referenced against the standard US mesh conversion table below.

Mesh (US)	Micron (µm)	mm	Inch	Remarks
3	6730	6.730	0.2650
4	4760	4.760	0.1870
5	4000	4.000	0.1570
6	3360	3.360	0.1320
7	2830	2.830	0.1110
8	2380	2.380	0.0937
10	2000	2.000	0.0787
12	1680	1.680	0.0661
14	1410	1.410	0.0555
16	1190	1.190	0.0469
18	1000	1.000	0.0394
20	841	0.841	0.0331
25	707	0.707	0.0278
30	595	0.595	0.0234
35	500	0.500	0.0197
40	420	0.420	0.0165
45	354	0.354	0.0138
50	297	0.297	0.0117
60	250	0.250	0.0098
70	210	0.210	0.0083
80	177	0.177	0.0070
100	149	0.149	0.0059
120	125	0.125	0.0049
140	105	0.105	0.0041
—	100	0.100	0.0039	Sand
170	88	0.088	0.0035
200	74	0.074	0.0029
—	70	0.070	0.0027
230	63	0.063	0.0024	Human hair
—	55	0.055	0.00217
270	53	0.053	0.0021
—	50	0.050	0.00197
325	44	0.044	0.0017
—	40	0.040	0.00157
400	37	0.037	0.0015
550	25	0.025	0.00099
625	20	0.020	0.00079
1200	12	0.012	0.0005
1250	10	0.010	0.000394
—	7	0.007	0.000276
2500	5	0.005	0.000197
4800	3	0.003	0.000118
5000	2.5	0.0025	0.000099	Bacteria (approx.)
12000	1	0.001	0.0000394

Information Required for Quotation

Grade / purity (e.g. ≥98–99%)
Particle size / target (nm or µm — please specify grade)
Quantity
Application environment
Required delivery country

Lead time depends on grade, particle size, quantity and processing requirements. Export availability can be reviewed based on destination country and material type. A Certificate of Analysis can be provided on request.

Request a Quote or Custom Order

Tell us your grade, particle size and quantity. We typically reply within one business day.

Frequently Asked Questions

What purity / grade options are available for Fused Silica Spherical Powder?

Fused Silica Spherical Powder is offered in the grades listed on this page (≥98–99%). Other grades can be reviewed on request depending on your application and quantity.

What particle sizes can you supply for Fused Silica Spherical Powder?

The typical size range supplied is 100nm–5µm grade ladder (fine sub-micron grades: 100nm, 0.3µm, 0.7µm; coarser 1–5µm+ grades also available). Please specify your target value in the request form and we will confirm availability.

Can Fused Silica Spherical Powder be made to custom specifications?

Yes. Fused Silica Spherical Powder can be produced to order — grade, particle size and packaging can be customized to your specification. Select “Custom Order” in the request form and provide your target values.

What is the minimum order quantity (MOQ)?

Order quantity is flexible and small quantities and prototype requests are welcome. Please state your required quantity in the form for an accurate quotation.

Can you export and ship Fused Silica Spherical Powder internationally?

Yes, export inquiries are welcome. Availability and shipping are reviewed based on destination country, grade and quantity.

Do you provide a Certificate of Analysis (COA) or technical data?

A Certificate of Analysis and technical data can be provided on request for supplied lots.

Request a Quote for Fused Silica Spherical Powder

Send us your grade, particle size, quantity and application. We will review availability, quotation and lead time. Small quantities, prototypes and custom made-to-order specifications are welcome.

Request a Quote

Fused Silica Spherical Powder (SiO2)