Ultra-Thin Polished Sapphire Substrates
Ultra-thin polished sapphire substrates, ranging from 25 to 200 microns thick and featuring various planes and precise optical finishes, provide high durability, chemical resistance, and broad wavelength transparency for use in optics, sensors, and harsh environments, with specific thicknesses and surface qualities available in stock from Valley Design.
Ultra-thin sapphire substrates are extremely thin, polished wafers of sapphire (crystalline aluminum oxide = Al2O3) with thicknesses usually ranging from 25 to 200 microns. They are thinner than standard sapphire wafers because they are specifically manufactured to be within this range or even thinner. Processes such as backgrinding, lapping, and polishing are used to reduce their thickness.
Sapphire is an extremely durable and tough material, characterized by a high melting point, resistance to radiation, and chemical corrosion. It has a high refractive index and is highly transparent across a broad spectrum of wavelengths, from UV to IR.
Sapphire’s properties make it the preferred material for various applications, including optical components, windows, sensors, high-voltage and high-frequency devices, and those operating in harsh environments that require mechanical stability.
Valley Design stocks Ultra-thin R-plane sapphire at 0.005″ thick and A-plane sapphire at 0.001″ and 0.002″ thick.
Also in stock at Valley Design:
- Various R-plane sapphire substrates: .005″, .010″, .015″, and .020″ thick, optically polished on both sides to a 40/20 scratch/dig surface finish.
- A-plane Sapphire disks and rectangles are available in thicknesses of .001, .002, .003, .004, .005, and .010 inches, polished on both sides with a 40/20 scratch/ding surface finish.
When polishing sapphire, the optical scratch/dig figures above roughly correspond to microinches or Angstroms Ra in the following common notations.
| Scratch/Dig |
Angstroms Ra |
Microinches Ra |
| 10/5 |
10A |
.040u” |
| 20/10 |
20A |
.080u” |
| 40/20 |
30A |
.12u” |
| 60/40 |
40A |
.16u” |
| 80/50 |
50A |
.2u” |
Note: Surface finishes for Fused Silica and glass are approx. 1/2 the value in angstroms or microinches as outlined above for Sapphire.
Other Sapphire Web sites:
For solutions to your complex technological needs, partner with the company that has consistently led in innovation, developing the processes and techniques now standard in manufacturing substrates and components for MEMS and many other applications. Contact us online or call 978-425-3030. Let’s work together to create something exceptional!