Electrical Failure Analysis

Our Electrical Failure Analysis labs support state-of-the-art techniques for in-silicon fault localisation and internal signal probing.

Electrical Failure Analysis services below:

Backside Packaging Silicon Access
patent USPTO 7,098,529

Advanced circuit analyses techniques require access to the back-side (silicon side) for the device under test (DUT). Except flip-chip, most packages do not permit access to the back-side and require complex and risky de-processing. Additionally, modern packages include connections in the package itself which, when deprocessed, make the device unusable.

Presto Engineering provides three analysis-ready package types which facilitate access to the back-side of the device, while allowing easy and flexible tester loadboard compatibility.

All packages are inverted cavity designs in order to preserve back-side access while socketed on a tester loadboard; all connections are routed in the outer section of the package itself, leaving the device area clear for analysis.

These packages are ready for our standard DUT cards, which connect to any of our testers--so all test and analysis interfaces are standard. This is the first step of a product debug project as it gets your device ready for backside techniques. Turn around time is typically 2 weeks.

Even with this fast turn around, this packaging step is best implemented at registration (as part of our release acceleration packages), while most of the preparation work is performed between tape-out and silicon, and can be readily available troughout qualification and validation.

Emission and Laser Systems

Our EFA labs operates combinations of Photo Emission Microscope and Laser Scanning Microscope systems.

Advanced optics equipped with a range of objective lenses (from macro to 100x) include Solid Immersion Lenses (SIL) for extreme resolution of the finest geomatries.

Navigation is typically supported by Knights.

Laser Scanning Microscopy (LSM) is performed with two lasers: 1064nm and 1340nm. A wide variety of applications are supported thanks to highly flexible scanning systems.

Photoemission (PEM) is provided through InGaAs cameras, a best-of-date combination between the relative limitation of traditional CDD units, and more complicated MCT cameras.

Our systems are inverted and can dock directly to any of the testers we have on our EFA floors, in order to provide all the dynamic analysis capabilities offered by emission and lasers.

All PEM and LSM analysis are best performed from the backside of the device. All optics are infra-red capable.

Finally, some of these systems are wafer capable, up to 300mm, and adapt to a mechanical probe station for wafer-level analytical applications.

FIB Circuit Edit

FIB Request Form  PDF 

Focused Ion Beam (FIB) has been in use for a long time, as a convenient way of altering silicon, for pre-mask validation, verification, design modifications, or probe point creation.

However, with increased number of metal layers, access to buried metal lines (known as "frontside" FIB) is becoming almost impossible. A novel way to use FIB has been first deployed in the mid-90s: backside FIB, or backside circuit edit.

The idea is to perform FIB from the silicon side. While frontside FIB is a fairly straightforward operation, usually performed within a day (as a walk-in type of activity), backside FIB requires a few additional steps:

• Provide silicon access (available with flip-chip; requires backside packaging for wire-bonded devices)
• Sample preparation: thin down silicon to (typically) 50-25μm, then polish
• Test electrically to ensure the device is still functional after sample prep
• On the backside FIB system:
  • Navigate optically to the region of interest (requires infra-red capability)
  • Trench down to 2-5μm of diffusion
  • Open up access holes to metal
  • Perform traditional FIB operation(s)

The IDS OptiFIB has been designed to support backside FIB; its ion column incorporates a coaxial optical path for simultaneously live optical and ion images. This allows precise backside alignment and beam placement, for modifications down to the 45nm process node.

Our team has been at the origin of the development of the IDS OptiFIB at Schlumberger, and has seen its deployment at over 20 customers since 1999. We have successfully performed hundreds of backside circuit edits.

Electron-Beam (E-Beam) probing

The E-Beam system can provide fast, accurate internal timing measurement, for analysis and fault diagnosis of ICs.

To generate an image, the IDS 10,000plus uses a finely focused electron beam, which is raster scanned over the surface of the device.

The Ebeam strikes the surface of the device, producing secondary electrons, which can be detected and processed to display the image.

By holding the beam on a specific conductor, it can function as a sampling oscilloscope, sampling voltage over time on that metal line. Thus, it provides non-loading, non-destructive, high bandwidth, low-noise measurements displayed as waveforms.

The system installed on our floor can be directly dock to any of our testers, using our PrestoConnect interfaces and cooling solutions (when needed).

Mechanical Probing

On our floor is a P300J motorized probe station from Micromanipulator.

With increased emphasis on advanced packaging engineering, an increasing number of projects rely on wafer-level characterization to accelerate product bring-up and initial validation.

Our probe station accommodates individual mechanical probing as well as probe-cards for parametric measurements and/or functional testing (linked to one of our ATEs).

The P300J probe station is a 300mm analytical probe station designed for low current, sub-micron positioning applications. It includes single-point ground, dry/dark environment, and integrated thermal chuck plumbing. Motorized controls provide a dynamic speed range which supports both precise positioning and long-distance moves. Both joystick and MicroTouchTM controls operate the station stage, platen (Z), and theta as well as the microscope X-Y and Z drives.

Configuration

• 300mm wafers
• Temperature range: up to +300° C
• Stage, Platen, Theta (300 x 300 x 50mm x 15 deg) range (0.1 micron resolution)
• Microscope 100 x 100mm (X-Y), x 200mm (Z) drive range (video available)
• Station joystick includes device select, high/low speed, and “lockout” buttons
• Stainless steel platen with 4-point platen leadscrew drive (supports both magnetic and vacuum base manipulators)
• Integrated dry/dark enclosure (EMF shield and enclosure for low temperature chuck dryness)
• High force chuck/theta post assembly (high pin count probe card pressures)