Pinpoint fault localization for semiconductor failure analysis — fast, sensitive, and proven.
The Industry Standard for Photoemission Localization
emmi™ gives failure analysis engineers a powerful, proven tool for detecting and localizing defects in semiconductor devices. By capturing photons emitted during electron-hole recombination, emmi™ reveals the precise location of gate leakage, dielectric breakdown, junction defects, oxide pinholes, and a wide range of other failure mechanisms — quickly and with exceptional sensitivity.
We owned the original patent on the photoemission technique, and emmi™ reflects decades of development in sensor design, software, and optics — delivering the high-quality, high-sensitivity images that the industry has come to rely on.
How Photoemission Microscopy Works
When a semiconductor device fails or operates in a degraded state, electron-hole recombination events release small numbers of photons. These emissions are extremely weak — often requiring integration times of several minutes — which makes sensor quality and noise performance the defining factors in system performance.
Reference Image
A reflected-mode image of the Device Under Test (DUT) is captured, providing a reference image of the device structure.
Emission Capture
Illumination is turned off, and an emission-mode image captures photoemission events from the device under power.
Image Overlay
The reference image and emission image are overlaid, precisely highlighting the location of emission sites on the DUT.
Fault Map
The result is a clear, spatially accurate map of fault locations — directly correlated to device structures.
Frontside and Backside Inspection Capability
Photoemission is an isotropic process — the same defect mechanisms that produce emission from the front of a device also produce emission from the backside. This makes emmi™ equally effective for both frontside and backside inspection workflows.
Backside inspection is increasingly important in modern semiconductor failure analysis, where device structures are difficult to access from the front. Because silicon substrates are transmissive to light wavelengths beyond 1,064 nm, our sensors designed for backside work operate in the near-infrared (NIR) spectral range. Substrates are typically thinned and polished prior to inspection to reduce scattering and absorption caused by substrate doping — and sample preparation tools for this purpose are widely available.
Sensor Selection — Matching Performance to Application
Selecting the right photoemission sensor requires careful consideration of failure type, supply voltage, and whether frontside or backside imaging is needed. High Quantum Efficiency (QE) is an important characteristic — but without equally strong signal-to-noise performance, QE alone can be misleading.
| Sensor | Best For |
|---|---|
| VisNIR-1024 | Deep depletion CCD — frontside and backside applications. Highest overall sensitivity across the full spectral range. |
| NIR-SWIR-320 | TE-cooled InGaAs sensor — added sensitivity for extended wavelength photoemissions. |
| NIR-SWIR-256 / NIR-SWIR-640 | LN2-cooled InGaAs sensors — maximum sensitivity for extended wavelength photoemissions requiring the lowest possible noise floor. |
| VisVNIR-512 | Frame Transfer CCD — high-sensitivity frontside inspection. |
| VisNUV-1024 | High-sensitivity visible and near-ultraviolet (NUV) photoemissions. |
| EM-128 | Electron multiplication CCD — designed for high-speed photoemission capture at up to 2,000 frames per second. |
| Spectral (Full Frame) | Discrete filter full image frame spectral photoemission for wavelength-resolved analysis. |
| Spectroscopy (Single Point) | High-resolution single-point photoemission spectroscopy for detailed spectral characterization. |
Why Sensor Quality Matters
Because photoemission in silicon is a weak process, sensor performance is critical. emmi™ sensors are cooled to reduce thermal noise and increase sensitivity, enabling detection of even the weakest emission events.
Our deep expertise in sensor selection, optical design, and software processing ensures that emmi™ systems deliver images that are not only sensitive but interpretable — giving engineers the confidence they need to reach correct failure analysis decisions.
Cooled Sensors
Thermally cooled to minimize dark current and reduce noise floor.
Low Noise Design
Captures the signal — not the noise — even at long integration times.
Interpretable Results
Spatially accurate images correlated directly to device structure.
Explore More QuantumScope™ Techniques
emmi™ is one of three complementary failure analysis techniques available on the QuantumScope™ platform. Depending on your device and analysis goals, you may also want to explore:
Laser Signal Injection
XIVA™ LSIM
Laser signal injection microscopy for soft defect localization — identifies faults that may not produce photoemission.
Get More Information About emmi™
Whether you’re evaluating emmi™ for your lab, comparing sensor configurations, or ready to discuss your specific application, our team is here to help.