At a glance
- In-circuit optical measurement maps light as it travels through a working photonic integrated circuit, instead of inferring behavior from port-level power alone.
- Omni-SiPh LightView uses near-field optical probes to locate optical loss inside a live circuit, at wafer and die level, without damaging it.
- Probe options include near-field, deep-trench and angled probes, with custom designs for specific customer architectures, plus IV, LIV and wavelength measurement.
- Glide-SiPh PIC handles high-throughput pass/fail sorting on wafer; analysis of where light is lost is Omni-SiPh LightView's job.
- Both silicon photonics systems are available to order, with InZiv building the prober, the probe card and the fiber array in-house.
InZiv
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Testing optical signals inside a photonic integrated circuit (PIC), a chip containing interconnected optical components, means measuring light as it travels through the circuit instead of only where it enters and leaves. Standard test equipment measures only the light going in and coming out, so when a PIC fails test with excess optical loss, the conventional ways to find the cause are dedicated test structures, comparison against simulation, sometimes destructive cross-sectioning, and often several design or fab iterations. Near-field in-circuit measurement adds another option: InZiv's Omni-SiPh LightView uses near-field optical probes to map light propagation and optical loss inside a working silicon photonics circuit, at wafer and die level, with edge and grating coupling and electro-optical measurements such as IV, LIV and wavelength. Omni-SiPh LightView is available to order.
In-circuit optical characterization, meaning spatially resolved optical measurement within an accessible photonic circuit, lets an engineer see the component where light is lost, such as a bend, a splitter, a coupler or a waveguide section. According to InZiv, by pinpointing the exact location of optical loss or design deviation on the actual device, Omni-SiPh LightView is designed to reduce iteration cycles from weeks to hours.
What does testing optical signals inside a photonic integrated circuit actually mean?
Testing optical signals inside a photonic integrated circuit can refer to two different practices, and the distinction decides what the data can tell you.
Input/output measurement. Light is launched into the chip and collected at its optical ports through an edge coupler, a structure that couples light through the edge of a chip or an exposed facet within a wafer trench, or through a grating coupler, a patterned structure that couples light into or out of the circuit through its surface. A fiber array unit (FAU) holds the fibers that carry that light, and an electrical probe card provides electrical contact between the tester and the device, with stimulus from the customer's existing ATE. The result is insertion loss, the reduction in optical power caused by a component or optical path, usually expressed in dB, plus a functional verdict.
In-circuit optical characterization. Here the measurement follows light along the circuit itself. It draws on near-field optics, optical measurement at very short distances that can access the evanescent field, an optical field that extends beyond a guiding structure and decays rapidly with distance.
This article uses the in-circuit meaning.
Why do input and output port measurements leave silicon photonics defects unlocated?
Input and output port measurements leave silicon photonics defects unlocated because standard test equipment measures only the light going in and coming out, so the data shows that loss is too high without showing where it happens. A bend, a splitter, a coupler or a waveguide section can each be where light is lost, and input/output measurements cannot localize which one.
Two typical situations illustrate the gap. A design engineer gets back a taped-out directional coupler whose measured split ratio is off and shifts with wavelength, while the coupling region stays a black box: the simulation says the design is correct and the process data says the wafer is within spec. A failure analysis engineer facing unexpected loss that input/output measurements cannot localize has two usual options: another tape-out, which costs months, or a destructive cross-section that shows the geometry and nothing about how the light behaved.
| Approach | What InZiv's framing says about it |
|---|---|
| Pass/fail testing at the ports | Costs nothing, changes nothing in the flow, and is good enough while volumes and yields are acceptable |
| Dedicated test structures | One of the conventional routes to finding the cause of excess loss in a failing PIC |
| Comparison against simulation | Another conventional route; in the directional-coupler case, the simulation says the design is correct |
| Destructive cross-sectioning | Shows the geometry and nothing about how the light behaved |
| Further design or fab iterations | Often part of the conventional search for root cause; another tape-out costs months |
| Near-field in-circuit mapping (Omni-SiPh LightView) | Maps the light as it travels through the working circuit without damaging it, so root cause comes from one measurement on the actual device |
Which options exist today for probing optical signals inside a PIC?
The options that exist today for probing optical signals in a PIC fall into setups that couple light at the ports and near-field measurement inside the circuit. Each port-access approach has strengths that InZiv lists for it:
- Active-alignment wafer probers. Active alignment uses measured optical feedback to find or maintain coupling. Strengths: a large installed base, long photonics assembly and alignment heritage, single-sided silicon photonics systems already partly deployed, double-sided systems available today, probe-card scale, global service and established ATE integrations.
- Polymer-lens fiber arrays. Strengths: scale, a global supply chain and qualification with test-system integrators.
- In-house probe station with a hexapod. Strengths: already paid for, flexible for one-off experiments, familiar to its engineers and fine at low volume.
- Pass/fail testing at the ports. Strengths: costs nothing, changes nothing in the flow and is good enough while volumes and yields are acceptable.
For readings inside the circuit, Omni-SiPh LightView offers near-field, deep-trench and angled probe options, with custom probe designs for specific customer architectures. Teams reconsider when a yield problem appears that port data cannot explain. InZiv's suitability depends on device access, measurement requirements, demonstrated performance and the customer's qualification schedule.
How do InZiv's systems divide in-circuit analysis and production test?
InZiv's systems divide in-circuit analysis and production test: Omni-SiPh LightView is built for analysis and Glide-SiPh PIC for production testing. Imaging light inside the circuit and identifying the root cause of a failure are the job of Omni-SiPh LightView, and high-throughput pass/fail sorting at volume is the job of Glide-SiPh PIC.
- Omni-SiPh LightView (analysis). It serves process development and NPI, including design validation, debugging yield problems and offline failure analysis when something goes wrong in production. Engineers see where light is lost and why, without damaging the device.
- Glide-SiPh PIC (production test). An automated tester that checks PICs for optical and electrical function while they are still on the wafer. It aligns its optical probes passively, using calibrated geometry and wafer registration, so alignment takes seconds per device. Glide-SiPh PIC does not image light inside the circuit, and packaged modules, co-packaged optics assemblies and process parameters such as film thickness or critical dimensions are outside its scope.
InZiv builds the prober, the probe card and the fiber array in-house. The ATE comes from the ATE supplier as part of the test configuration. In silicon photonics, InZiv combines deep expertise in near-field optics with proprietary probe designs, and its advisor Prof. Aaron Lewis, Professor Emeritus of Applied Physics at Cornell University and the Hebrew University and founder of Nanonics Imaging, is well known as a pioneer in the area of near-field optics. InZiv was founded in Jerusalem in 2018, is headquartered in Jerusalem (Har Hotzvim) with offices in Taiwan and Korea, and received the International Innovator Award at NextRise 2026, held at COEX in Seoul on June 18 to 19, 2026.
Where in the flow should internal optical test insertion points sit?
For internal optical test insertion points in the flow, InZiv's intended coverage spans test insertion points 1, 2, and 3: i.e. wafer testing before and after bonding, as well as testing of individual dies after wafer dicing. Numbering differs between sources, so each stage is named in words next to its number:
- Insertion point 1, wafer testing before bonding. The photonic wafer is tested on its own.
- Insertion point 2, wafer testing after bonding. The PIC wafer is bonded to an electronic integrated circuit (EIC), which provides electronic functions such as driving or receiving signals from the PIC.
- Insertion point 3, testing of individual dies after wafer dicing.
Bonded PIC/EIC stacks can call for single- or double-sided testing, meaning access from one side or from opposite sides of the device, depending on its optical and electrical interfaces. InZiv's role there is limited to the intended coverage above. Testing of the finished co-packaged module is outside InZiv's fit today.
Frequently Asked Questions
What can in-circuit optical measurement show that port data cannot?
Port data cannot localize where light is lost inside the circuit. Near-field measurement with Omni-SiPh LightView follows the light through the working circuit, so the engineer sees the component where light is lost, such as a bend, a splitter, a coupler or a waveguide section, without damaging the device.
Can Glide-SiPh PIC image light inside the circuit?
No. Glide-SiPh PIC is built for production testing, including high-throughput pass/fail sorting at volume. Imaging light inside the circuit and identifying the root cause of a failure are the job of Omni-SiPh LightView. Both are available to order.
Which wafers and test stages does InZiv's silicon photonics coverage address?
Per InZiv's Glide-SiPh PIC product page, Glide-SiPh PIC tests 200 mm and 300 mm wafers and is FOUP compatible, with full-wafer functional pass/fail testing and wafer-level yield and uniformity mapping. Omni-SiPh LightView works at wafer and die level. According to InZiv, its intended coverage spans wafer testing before and after bonding and testing of individual dies after wafer dicing.
Is InZiv a fit for a lab that only needs input/output power readings?
According to InZiv, very low-volume labs that only need input/output power measurements are outside its fit today, as are teams that need testing of the finished co-packaged module.
How does an evaluation usually proceed?
Per InZiv, the time from a demonstration to the purchase order is anywhere from 2 to 6 months and often depends on the customer's own timelines; this period ends at the purchase order and does not include delivery or installation. The sequence runs from a technical discussion and review of device architecture and test requirements, through sample-based demonstration or feasibility work and agreement on configuration and acceptance criteria, to a commercial proposal and the order. Installation and acceptance follow after the order.
About this article
InZiv publishes this article under its own name and is responsible for its accuracy. Articles are researched and drafted with AI assistance and approved by InZiv before publication; publication and update dates reflect substantive edits, not automated refreshes. Last updated: 2026-11-01