Product Specification

Product Overview

Custom sapphire spacers—also known as sapphire shims or sapphire washers—are precision–machined components made from single-crystal aluminum oxide (Al₂O₃, 99.99%). These spacers are designed for applications that demand high mechanical strength, dimensional stability, and excellent resistance to chemicals, heat, and wear.

Unlike optical-grade sapphire windows, these spacers are supplied in an unpolished finish, making them ideal for structural, mechanical, and thermal support rather than optical transmission.

Sapphire’s Mohs hardness of 9 and its outstanding thermal and chemical durability make unpolished spacers a robust choice for semiconductor tools, precision instruments, and special fixtures where long-term reliability is essential.

Key Features

• Unpolished Finish
  Surface is lapped or ground without optical polishing; suitable for non-optical structural applications.

• Ultra-High Hardness
  Mohs 9 hardness provides excellent wear resistance compared with glass, quartz, or ceramics.

• Exceptional Mechanical Strength
  High compressive strength and stiffness ensure stability under load.

• Thermal Stability
  Working temperature up to 1600°C in air and 2000°C in vacuum or inert environments.

• Chemical Resistance
  Inert to most acids, alkalis, plasma, and solvents—ideal for harsh industrial environments.

• Customizable Shapes
  Available in discs, rings, rectangles, squares, stepped shapes, and complex geometries.

Manufacturing Process (Unpolished Type)

1. Crystal Cutting – Slicing from high-purity synthetic sapphire boules (C-plane / A-plane / R-plane available).

2. Shaping & CNC Machining – Outer diameter, inner diameter, and thickness customized to drawing.

3. Grinding / Lapping – Achieve flat or semi-flat unpolished surface finish.

4. Chamfering or Edge Smoothing – Optional to prevent chipping.

5. Cleaning & Inspection – Final dimensional checks and debris removal.

Typical Applications

• Semiconductor equipment – Spacers for wafer carriers, furnace boats, plasma chambers.

• Precision machinery – High-load, high-wear shims and gap-adjustment components.

• Opto-mechanical assemblies – Structural spacers around optical components.

• High-temperature fixtures – Support pieces in thermal processing tools.

• Chemical-resistant assemblies – Used where polymers or metals would degrade.

• Vacuum instruments – Non-outgassing, stable, and extremely durable.

Available Specifications

(Customizable according to drawings)

• Outer Diameter: 2–200 mm

• Inner Diameter: As required

• Thickness: 0.1–20 mm

• Shape: Round / Square / Ring / Rectangle / Slotted / Custom

• Surface: Unpolished (ground / lapped), single-side or double-side

• Tolerance: ±0.02–±0.1 mm depending on size

• Crystal Orientation: C-plane (0001) standard; A/R-plane optional

Why Choose Sapphire Instead of Ceramic or Quartz?

Sapphire spacers maintain precision and rigidity even after long-term exposure to plasma, heat, or mechanical stress.

FAQ

Q1: What is the surface roughness of unpolished sapphire spacers?
A: Typically Ra 0.4–1.2 µm (varies by grinding process). Optical polish is not applied.

Q2: Can you produce both single-side and double-side unpolished surfaces?
A: Yes. Both sides can be ground, or one side can remain semi-processed.

Q3: Are custom drawings supported?
A: Absolutely. We support DXF, PDF, STP, SolidWorks files, and complex shapes.

About Us

ZMSH specializes in high-tech development, production, and sales of special optical glass and new crystal materials. Our products serve optical electronics, consumer electronics, and the military. We offer Sapphire optical components, mobile phone lens covers, Ceramics, LT, Silicon Carbide SIC, Quartz, and semiconductor crystal wafers. With skilled expertise and cutting-edge equipment, we excel in non-standard product processing, aiming to be a leading optoelectronic materials high-tech enterprise.