IN Brief:
- Iris 100 measures spectral response, per-pixel luminance, uniformity, and defects across arrays containing hundreds of thousands or millions of microLEDs.
- Direct UltraFLEXplus integration combines optical and electrical measurement within an established semiconductor production test environment.
- The platform supports wafer and final test, with photodetector testing planned for the same insertion.
Teradyne has introduced Iris 100, a production optical test platform designed to measure individual emitters across microLED arrays while integrating with its UltraFLEXplus semiconductor test environment for combined optical and electrical characterisation.
The system uses a spectrometer and high-resolution camera to measure array spectral response, per-pixel luminance, and uniformity. Teradyne combines those instruments with image-processing algorithms and parallelised test methods intended to characterise complete arrays containing hundreds of thousands or millions of individual emitters at manufacturing throughput.
That requirement becomes increasingly difficult as microLED devices move from engineering samples into applications where one defective emitter can affect the finished product. Teradyne is targeting augmented-reality microdisplays and optical data interconnects for AI datacentres, both of which place large numbers of small emitters into tightly controlled optical systems.
Iris 100 detects dead or stuck pixels and clusters of defective emitters before additional manufacturing value is accumulated around the device. The platform supports wafer and final test, allowing optical inspection to be introduced before packaging as well as after the device has reached a more complete assembly stage.
MicroLED yield presents a different test problem from conventional electrical semiconductor screening. An array can power correctly while still containing emitters that fall outside wavelength, luminance, or uniformity limits. Measuring those properties across millions of pixels creates a throughput problem if each emitter is treated as a separate laboratory measurement.
Teradyne is addressing that problem using the same production-test framework applied to complex semiconductor devices. Iris 100 connects directly with UltraFLEXplus and uses the company’s IG-XL environment, keeping optical measurements within a wider tester architecture rather than creating an independent inspection station with a separate development and data workflow.
The system also uses NIST-traceable calibration to produce absolute measurements intended to correlate between wafers, production lots, and manufacturing sites. Correlation becomes particularly important where optical acceptance limits have to remain consistent across several stages or factories rather than being interpreted differently by individual instruments.
Optical and electrical measurements are closely linked in a microLED array because each emitter has to be driven under defined electrical conditions while its light output is measured. Combining both functions in the same test insertion allows manufacturers to relate optical defects more directly to electrical behaviour and reduces the need to transfer devices between separate platforms.
The new system extends Teradyne’s recent expansion of the UltraFLEXplus platform. Earlier this month the company added instruments for deeper digital patterns, PCIe Gen6 testing, and multi-kiloamp power delivery. Iris 100 broadens the same production environment into optoelectronics, where electrical test alone cannot determine whether the finished device meets specification.
Optical interconnects add another manufacturing challenge. MicroLED arrays proposed for highly parallel data links have to maintain consistent output across large numbers of optical channels, placing wavelength, power, and uniformity directly inside the communications budget. Defects that might be cosmetically acceptable in another application can become functional failures when individual emitters represent separate data paths.
Teradyne plans to extend Iris 100 to photodetector testing within the same insertion. That would bring emitter and receiver measurement into a related production architecture as optical interconnect technologies mature, although the company has not given a timetable for that addition.
The production economics now matter as much as measurement capability. Test time, calibration stability, equipment utilisation, and the amount of defective material removed before expensive packaging will determine whether comprehensive optical screening lowers overall manufacturing cost.
Iris 100 turns microLED characterisation from a laboratory metrology problem into a semiconductor-test problem. Its adoption will depend on whether per-emitter measurement can remain fast enough for volume manufacturing while preserving the optical precision required across very large arrays.
