Product Overview

Used in chemical metering pumps, precision dispensing systems, and fluid handling equipment in semiconductor wet processing and analytical instruments. Fountyl high-precision ceramic pistons are manufactured from alumina (Al₂O₃ 99.5%) and silicon carbide (SiC 99%) ceramics with a piston-to-cylinder clearance of 3 um. The tight clearance eliminates the need for elastomer seals, preventing particle generation, chemical degradation, and seal wear that compromise fluid purity and dosing accuracy.

The piston surface is lapped to sub-micron surface finish and cylindrical form. The combination of ceramic hardness, chemical inertness, and precision geometry enables accurate, repeatable displacement over extended service life.

Material Specifications

Alumina Ceramic (Al₂O₃ 99.5%)
- Flexural strength: >= 330 MPa
- Vickers hardness: >= 1600 HV
- Thermal expansion: 8 ppm/C

Silicon Carbide Ceramic (SiC 99%)
- Flexural strength: >= 450 MPa
- Vickers hardness: >= 2500 HV
- Thermal expansion: 4 ppm/C

Dimensional Specifications

- Piston diameter: 5-50 mm
- Piston length: up to 200 mm
- Piston-to-cylinder clearance: 3 um (single-side gap)
- Roundness: <= 0.5 um
- Cylindricity: <= 1 um
- Surface roughness: Ra <= 0.05 um (lapped)
- Diameter tolerance: +/- 1 um

Key Features

- 3 um clearance -- precision fit enables seal-free operation. No elastomer contact, no seal wear, no particle generation.
- Chemical inertness -- resistant to acids, bases, and solvents used in semiconductor wet processing. No corrosion, no fluid contamination.
- Wear resistance -- hardness up to 2500 HV maintains dimensional accuracy and clearance over millions of cycles.
- Lapped surface -- Ra <= 0.05 um reduces friction and prevents fluid residue buildup on the piston surface.
- Dimensional stability -- low thermal expansion maintains clearance across operating temperature range.
- Custom geometry -- stepped diameters, internal bores, and mounting features available to match specific pump designs.

Applications

- Chemical metering pumps in semiconductor wet etch and cleaning tools
- Photoresist and chemical dispensing systems
- Precision dosing pumps in analytical and pharmaceutical equipment
- Fluid handling in CVD and ALD precursor delivery systems
- High-purity liquid transfer in fab chemical delivery modules

Manufacturing Capability

In-house production through powder processing, sintering, precision cylindrical grinding, lapping, and final inspection. Each piston is measured for roundness, cylindricity, diameter, and surface finish. Custom diameters, lengths, and feature geometries available for OEM pump integration.