Does this match your preferences? Make a selection.
Structured glass wafer for wafer-level optics and scalable optical integration

Wafer-level optics: Precision at scale

Wafer-level optics compress hundreds of optical elements into a single manufacturing step. When optical function is replicated across an entire wafer, even small deviations scale with it. Reliable performance therefore depends on substrate precision and material stability.
Overview

When optical scaling meets material realities

Wafer-level optics represent a paradigm shift in optical system design, enabling the production of highly compact, scalable, and reproducible optical components. By fabricating hundreds or thousands of optical elements on a single wafer, this technology achieves unprecedented miniaturization. . However, it comes with a critical trade-off: the loss of corrective flexibility inherent in traditional optics.

In wafer-level optics, optical performance is locked in before calibration, software adjustments, or even the first pixel capture. Once the wafer is processed, any deviations are replicated across every element, leading to uniform signal degradation. This makes wafer-level optics fundamentally a material challenge, where the substrate dictates success.

Challenges

The challenge: Scaling without a safety net

Unlike traditional optical assemblies – where alignment, spacing, and adjustments can compensate for imperfections – wafer-level optics do not offer such luxuries. Here, thousands of optical elements share a single foundation: the substrate.

Three critical factors influence optical signal integrity in wafer-level optics:

  • Wafer-wide TTV and warpage: They create focus variations across sensor arrays, compromising uniformity.
  • Cumulative misalignment: Stacked elements reduce signal fidelity before detection even begins.
  • Thermal behavior: Temperature cycling shifts optical paths, destabilizing performance over time.

These factors collectively define yield, consistency, and long-term reliability.

Technician holding a precision glass wafer used as substrate for wafer-level optics
Role of glass

Glass: The backbone of wafer-level optics

In wafer-Level optics, whether for diffractive optic elements (DOE), diffusers, or microlens arrays, glass is not just chosen for its optical clarity. It is the key to stability, reproducibility, and scalability.

To succeed, the substrate must deliver:

    Flawless planarity and thickness homogeneity
    Flawless planarity and thickness homogeneity
    to ensure consistent optical function across thousands of elements.
    Uniform refractive index and controlled dispersion
    Uniform refractive index and controlled dispersion
    for precise optical behavior replication.
    High transmission in VIS and NIR ranges
    High transmission in VIS and NIR ranges
    to preserve signal integrity before amplification.
    Controlled thermal expansion (CTE)
    Controlled thermal expansion (CTE)
    to maintain alignment and optical path stability under thermal stress.
    In short, wafer-level optics demand glass engineered for process stability as much as optical performance.
    Materials

    Glass solutions for wafer-level optical components

    Different applications require different substrate properties. The following high-performance glass materials are tailored for wafer-level optics:

    D 263® T eco

    With tight thickness tolerances, minimal total thickness variation, and superior surface quality, D 263® T eco supports high-fidelity replication, lithography, and optical stacking. Its stable refractive index and excellent transmission make it perfect for large-scale production.
    Explore D 263® T eco
    D 263® T eco thin glass substrates for wafer-level optics and precision optical components

    AF 32® eco

    The low coefficient of thermal expansion and homogeneous optical properties of AF 32® eco ensure alignment and performance stability through thermal cycling, reflow, and long-term operation – ideal for silicon-bonded applications.
    Explore AF 32® eco
    AF 32® eco thin glass substrate with low thermal expansion for wafer-level optics

    BOROFLOAT® 33

    For architectures requiring excellent thermal compatibility with silicon.
 Its coefficient of thermal expansion (CTE) closely matches that of silicon, making BOROFLOAT® 33 particularly well suited for wafer-level optical systems where reliable bonding and dimensional stability are critical. This CTE match enables processes such as anodic bonding, providing a strong and hermetic alternative when adhesive or frit bonding are not suitable. In addition, BOROFLOAT® 33 supports a wide range of bonding approaches, from UV bonding to anodic bonding technologies.
    Explore BOROFLOAT® 33
    BOROFLOAT® 33 glass substrates used for wafer-level optics and silicon bonding
    Choosing the right material depends on optical design, wavelength range, wafer size, and manufacturing process. Early substrate selection is crucial for predictable performance.
    Applications

    Where wafer-level optics are in action

    Wafer-level optics do not sense directly. They enable the compact, reproducible optical components that power modern sensing applications:

    CMOS image sensor module used in 3D sensing applications

    Imaging and sensing

    In compact imaging systems, optical signal quality is defined at wafer level before any correction is possible. Even minimal variations in thickness, alignment, or refractive index directly impact signal-to-noise ratio and image consistency. Material precision ensures reproducible optical performance across integrated sensor architectures.
    Driver view with digital sensing overlay representing automotive perception systems

    Automotive sensing

    Automotive sensing systems rely on stable optical performance under vibration, temperature cycling, and long-term stress. In wafer-level optics, these conditions directly affect alignment and optical paths across entire sensor arrays. Material stability defines whether perception remains reliable over the full lifetime of the vehicle.
    User interacting with smartphone using face recognition sensing technology

    Mobile sensing

    Mobile sensing pushes miniaturization and scale to extremes, where thousands of optical elements are replicated per wafer. Any deviation is multiplied across millions of devices, directly affecting sensing accuracy and user experience. Material uniformity and stability determine whether performance remains consistent without calibration.
    Future

    The future: Structure over assembly

    As wafer-level architectures advance, optical function is increasingly embedded in surfaces and geometries, replacing traditional assembly methods:

    Nanostructured metalens surface for compact planar optical systems

    Metalenses

    Optical function is embedded directly into nanostructures, eliminating the need for multi-element assemblies. Performance depends on how precisely geometry and material properties are controlled, with no possibility for post-production correction.

    Explore metalenses
    Nanoimprint lithography wafer used for nanoscale optical structure replication

    Nanoimprint lithography

    Nanoimprint enables scalable replication of nanostructured optical functions across entire wafers. Material fidelity defines whether optical performance can be reproduced consistently without alignment or adjustment.

    Start your wafer-level optics project

    Discuss substrate requirements, manufacturing constraints and scalable optical architectures with SCHOTT experts.

    Martin Naß

    Martin Naß

    Product Manager sensing vision
    +496131663932

    *Field is required

    SCHOTT will use your data only for reacting to your inquiry. For more information, please click here.

    See the bigger picture of sensing performance

    Material properties define how systems behave. Explore how signal quality, system architecture, and real-world conditions shape sensing performance across applications.
    Explore sensing vision