Glass Carrier Wafer and Glass Carrier Panel

Glass Carrier

The semiconductor industry relies on glass carrier wafers to enable 3D packaging for IC devices, such as CMOS image sensors, MEMS, and fan-out wafer-level packaging (FO-WLP). These carrier wafers bond ultra-thin semiconductor wafers during manufacturing to ensure safe handling and prevent damage.

What are glass carrier wafers?

Glass carrier wafers are precision disks of thin glass, such as borosilicate glass and alumino-borosilicate glass. They are created by selecting an appropriate high-quality glass material and then carefully cutting and shaping it. 

Why glass is ideal for semiconductors

Used throughout the semiconductor industry, carrier wafers and carrier panels are commonly used to manufacture essential components such as 3D ICs and FO-WLP. In order to withstand the high temperatures required for semiconductor manufacturing, carrier wafers and panels are usually made using a material with high thermal stability.

Carrier wafers date back to the earliest days of semiconductor manufacturing. Initially, the manufacturing process used silicon wafers as carriers, but materials such as glass and ceramics were later introduced. Glass is now a common substrate for carrier wafers and is increasingly important in the fast-moving world of semiconductors for a number of reasons.

Advantages of glass carrier

Glass carriers are becoming increasingly important in the fast moving world of semiconductors. This is due to the following key properties:

High raw glass quality

High reproducibility of our melting processes ensures high and consistent quality of raw glass.

Broad CTE range

This allows a range of materials to be placed as carrier wafers during semiconductor processing, with a closely matched CTE for optimal results.

Mechanical robustness

Excellent processing performance of carrier wafers results in extraordinary robustness in areas such as breakage strength.

Chemical and high temperature resistance

Glass is an excellent material for carriers thanks to its high resistance to acids and other chemicals, as well as its excellent thermal shock properties.


The transparency of glass carriers enables a laser debonding process and allows in-process inspection. It also facilitates the identification of any bonding problems that may occur.

Extremely low tolerances

Carrier wafers offer a TTV level of ≤ 3µm, enabling superior silicon wafer thinning and a warpage of ≤ 50µm, avoiding higher warpage during the layer stacking process.

Form and shape

Glass is ideal as a carrier substrate as it offers fewer size limitations. Produced as a wafer, it has the same notch and chamfer geometry options as silicon wafers, with the added benefits of glass.

Cost-effective and durable

Thanks to its superior properties, glass carrier wafers and panels can be used up to 10 times, increasing the sustainability of these critical components while decreasing costs.

Ready for back-end processes

Glass carriers enable silicon wafer/die handling in semiconductor production.

Broad choice of materials for glass carrier to fit customers requirements

SCHOTT glass portfolio with a broad CTE range to meet customer device materials due to our broad choice of materials we can fulfil our customers requirements.
Graph showing the CTEs of a variety of SCHOTT glasses

G1, G2  are alkaline free materials 

G1, G2 and G3 carriers match  Si - wafer CTE 

G5 and G6 meet high CTE of compound and other interface material

Geometrical properties of SCHOTT Glass Carrier

Geometrical properties Value

Ultra Low Total Thickness Variation (TTV)

≤ 3µm (Standard)
≤ 1µm (Advanced)

Precise Thickness Tolerances

± 10 μm (Standard)
± 5 μm (Advanced)

Warp (Depending on materials and thicknesses)

≤ 50µm (Standard)
≤ 30µm (Advanced)

 Cosmetic Quality (Depending on materials and thickness)

20/10 (Standard)
10/5 (Advanced)

Bonding and debonding of glass carrier

High UV transmittance allows temporary bonding and debonding
Graph showing the optical transmission of SCHOTT Glass Carriers

Spectral transmittance: thickness 1.1 mm for λ = 250 nm to 400 nm

Graph showing the optical transmission of SCHOTT Glass Carriers200-500 nm-EN

Spectral transmittance: thickness 1.1 mm for λ = 200 nm 500 nm

SCHOTT Glass Carrier can be delivered as follows:

  • Flat/notch: According to SEMI standard
  • Laser marking: Barcode/unique number
  • Cleaning: Ultra/mega-sonic cleaning and cleanroom ISO 6
  • Packaging: Inspection and packaging under ISO 6 in wafer boxes (FOSB, RTU, etc.)