Sample Preparation Solutions forâ€Ś Electrical and Physical Failure Analysis
Package and Die Level Deprocessing
The X-Prep® is a specialized 5-axis CNC-based milling/grinding/polishing machine designed to support electrical and physical failure analysis techniques and other applications requiring high precision sample preparation. Fault Localization – Electrical (EFA) •
Package Level •
TDR, GMR/SQUID, Lock-In Thermography (LIT)
Die Level •
Photon/Thermal/Laser/Magnetic-based response, SEM-PVC, FIB (circuit edit), eBeam Probing, atomic force probing (AFP)/nano-probing
Defect Identification – Physical (PFA) •
Package Level •
Die Level •
Acoustic, pre-chemical decapsulation, substrate delayering SEM, SIMS, frontside delayering
Failure Analysis Tools & Methods Supported
CSAM – Scanning acoustic microscopy
FIB – Focused ion beam – circuit edit/repair
LADA – Laser assisted device alteration
LIVA – Light induced voltage alteration
LVP – Laser voltage probe
OBIC – Optical beam induced current
OBIRCH – Optical beam induced resistance change
PEM – Photo emission microscopy (EMMI)
SIMS – Substrate thinning and polishing
TIVA – Thermal induced voltage alteration
VLVP – Visible laser voltage probe
Die & Package Level Device Examples 3D TSV – Stacked Die •
Flip-Chip - GPU
SoC, PoP, and SiC – mobile processors
Hybrid Super SoC’s
WL/CSP – Wafer and chip-scale package
2.5D Devices - FPGA
Lead – Frame •
TSOP – Thin small outline package
SSOP – Shrink small outline package
SOIC – Small outline IC
DIP – Dual inline package
Leadless – Quad
PLCC – Plastic leaded chip carrier
QFN – Quad flat no-lead
QFP – Quad flat package
Sample Prep Examples/Results
Pre-chemical decapsulation â€“ Cu bond wire
Silicon die thinned to near transparency through the backside MOSFET/Bipolar device FA
QFN Multi-chip power module
Circuit board delayering
3D Capability The X-PrepÂŽ 3D is useful for package deprocessing and die thinning for electrical fault localization methods that demand extreme uniformity of material removal and final thickness control. This capability is ideal for warped substrates that feature either convex or concave geometry. The advantage of deprocessing a device following its physical profile is that it remains in its â€œasmanufacturedâ€? physical state. This approach increases accuracy of material removal and reduces the risk of either mechanically induced or post-processing stress relaxation damage such as cracking and/or delamination. The functionality includes the capability to use and/or create custom/predictive maps to control the milling profile. Both symmetrical and asymmetrical profiles can be used and adjusted to match the physical changes encountered, providing a high degree of versatility to the operator.
Flat-plane deprocessing (left) produces nonuniform material removal and thickness. Deprocessing the device by following its profile (right) ensures uniform material removal.
3D Capability – Concave – Package Level
In Support of… • Package-level failure analysis • TDR, GMR/SQUID & Lock-In Thermography (LIT) As packaging technology continues to advance, the physical profile and shrinking density render the use of flat-plane sample preparation tools obsolete due to nonuniform deprocessing. The X-Prep® 3D overcomes these challenges and enables uniform deprocessing of all device types. Leading-edge technology and advanced components utilizing a closed-loop control system ensure unmatched accuracy and precision.
Uniform FR4 substrate delayering
• Stacked die deprocessing – X-ray image before (top) and after (bottom) • 8-layer die stack deprocessed to die 7 Uniform copper (Cu) pillar • 4-layer board deprocessed to layer 1 deprocessing - molded package, stacked die
3D Capability – Convex – Die Level
In Support of… • Laser/Photon EFA Tools
Convex/Curved die profile
• High NA SIL • Visible SIL (10 nm technology nodes & beyond)
• High-Throughput FIB processing • Design debug/circuit edit
Obtain uniform remaining silicon thickness!
• Nano/e-Probing Electrical failure analysis toolsets continue to develop at a pace significantly faster than sample preparation techniques. New solid immersion lenses (SILs) have been developed that require tighter tolerances of silicon thickness for imaging through the backside. Traditional silicon thinning sample preparation techniques that utilize a flat-plane grinding/polishing process do not account for the device bow and have become obsolete. High-precision sample preparation with the X-Prep® 3D produces uniform (edge-to-edge) remaining silicon thickness by following the natural curvature of the die. The device remains in its physical (manufactured) state and no thermal or mechanical stress/strain is introduced. The die may be thinned (without cracking) to any target thickness or to as little as 5 microns.
+/- 3 μm Uniformity & Ultra-thin
• High NA SIL • Optical Probing • SIMS
Dynamic relaxation of the package that occurs to the die as it is thinned causes the physical die profile to change, resulting in nonuniform remaining silicon thickness, or RST. Measurements of the substrate are therefore needed to adjust the physical tool profile to compensate for relaxation and allow thinning to tolerances better than +/- 3 microns from target thickness. The X-Prep® Vision™ measures the RST quickly and easily at the click of a button. The RST data is then used to modify the physical tool profile prior to polishing.
Thin silicon to optical transparency!
See page 24 for product details
Featured Highlights • 3D capability enables convex and concave profile deprocessing • Closed-loop design ensures end-point precision and
• HD Camera provides razor sharp resolution and sample imaging • Guided workflow simplifies operation and minimizes the “learning curve” – regardless of experience • Safety interlocked cover prevents operator access to spindle during operation • Electronic proximity control prevents tool collision with fixture • Tool-free fixture and tool interchangeability • Quiet operation – ~15-20 dB over ambient • Tool length detection ensures safe operation • LED ring light provides full illumination above the sample 10
• Designed, engineered and built by Allied in the USA
Technical Features/Capabilities X & Y Axis
• 1 μm resolution, 100 x 100 mm stage travel • Multiple tool path and overlap options • Selectable rate from 0.1 to 20 mm/s
• • • • •
Z-Axis • • • •
Closed-loop design 0.1 μm resolution 1 μm accuracy Three (3) modes of control: • Position (Milling/Grinding) • Position Force (Grinding/Polishing) • Floating Force (Polishing)
12" color touch-screen Wizard-guided GUI Built-in help menus with instruction High definition (720p) live video X/Y definition Store and recall of steps & sequences
Spindle • • • •
Variable spindle RPM: 5,000 – 100,000 Pneumatic tool change Powerful 3-phase AC current Uses tools with 3 mm Ø shank x 38 mm L
Tilt • Dual-axis tilt control, 0.5 μm resolution • Automatic 3-point sample leveling • Level plane • Angle specific
Operation â€“ Intuitive, Versatile, Easy-to-Use The X-PrepÂŽ features a user-friendly, intuitive interface. As each screen appears in sequence, instruction is provided to the operator, ensuring every parameter and function is defined before operation so that no detail is overlooked. Graphic icons are found on many of the buttons for ease of identification. Help buttons on each screen provide access to additional explanation and instructions for each operation. This quickly provides a reminder and training to those who infrequently use the machine.
A Help (?) button on every screen provides specific instructions to the operator.
A high-definition (720p) color camera projects a magnified, razor-sharp image of the sample onto the touch-screen or external LCD monitor to help the operator define the X/Y boundary. The active display shows X + Y axis position as the stage moves the sample in reference to the crosshair. Zeroing enables measurements and sets the origin. The four-way arrows provide variable speed movement of the fixture/sample. Two buttons set X and Y distance to define the X/Y boundary. 12
Automatic Tilt Correction/Leveling Tilted
Automatic Sample Leveling Tilt adjustment (a standard feature) allows leveling the sample plane so it is parallel to the X/Y plane of the tool. Unevenly mounted or tilted samples can easily be leveled using this functionality. Contact on three points provides height data that is used to calculate the amount of adjustment needed. An automatic adjustment is made and it loops until the set tolerance has been achieved. Additional capability enables the operator to position the three points anywhere on the surface of the plane. The distance of lift between points can be set up to 20 mm to clear surface mount capacitors or other obstacles on the plane. The tolerance range can be defined from 0.5 to 100 Îźm. In cases where an angle other than parallel to the plane is desired, adjustment is also possible using the custom tilt function.
The difference in height between the points of contact on each axis are displayed on the touch-screen. Indication of tilt axis is provided by the +/- symbol/value.
System Information The X-Prep® is an ideal tool for any laboratory involved with precision sample preparation to support various analytical methods. It is exceptionally useful in supporting microelectronic device failure analysis labs. Additional applications can be found in the medical, MEMS and optical device/component fields. The table-top, compact footprint requires little space. The operation interface is simple to use, making it a more appealing tool to a greater number of people without any significant training. The wizard-based software guides the operator through a screen sequence to simplify use and reduce reliance on memory and skill. The information created can be captured and stored into the system memory and recalled for later use. Backup to a memory card ensures protection of data. Item No. 15-9550 15-9550-230
Description X-Prep® - 115V AC X-Prep® - 230V AC
3D Software Module – Convex & Concave • Adds both convex & concave deprocessing capability • Can be purchased and added at a later time
Assortment Consumable Kit – see quote for details
Standard system configuration includes 2” sample holding fixture See following pages for accessories and consumables. Several options for training are available – please contact your Allied representative for further details. 14
Accessories Fixtures Each fixture is designed to accommodate a carrier insert onto which samples are mounted using wax. Wax offers an advantage over clamping when dealing with delicate samples, or for those so small that clamping is not an option.
Borosilicate (glass) carriers maintain their shape through thermal cycling required to melt and harden wax. It is easily machined using diamond tools to produce pockets to accommodate items such as leads on device packages, capacitors or flip-chip die.
Aluminum carriers can also be easily fitted into these fixtures and used as an alternative to glass for applications that require the carrier to provide electrical conductivity. All fixtures allow the sample to be submerged in lubricant to maintain lower temperatures for improved tool life and sample preservation as well as capturing particulates from becoming airborne. SmartCard
Item No. 15-9125 15-9135 15-9140 15-9147
Description 2" x 2" (50 x 50 mm), with 20 borosilicate carriers (#15-9126) 3" x 3" (75 x 75 mm), with 10 borosilicate carriers (#15-9136) 4" x 4" (100 x 100 mm), with 10 borosilicate carriers (#15-9141) 4" x 6" (100 x 150 mm), with 10 borosilicate carriers (#15-9148)
Dust Extraction Vacuum, HEPA Filtration This quiet, vacuum provides maximum health protection from exposure to airborne contaminants generated from dry cutting and/or grinding processes. It features a triple filtration system with a carbon and micro-filter that are easy to change. Its automatic control operates the unit only when suction is required. Noise: ~ 15-20 dB over ambient. Item No. Description dB CFM W H2O Lift 15-9180 Vacuum System, 115V AC 60 106 1200 98" 15-9185 Vacuum System, 230V AC 60 106 1200 98"
Consumables – Cutting Metal & Circuit Board Carbide End Mills End mills are intended to be predominantly used to cut metal and/or metal alloys. Allied offers a complete line of solid carbide end mills whose item numbers appear in three (3) columns in the chart, each optimized for cutting the following three (3) material categories: PCB – FR4 Substrate Aluminum (Al) and/or Copper (Cu) Ferrous (Fe) Alloys – Steel, NiCo
Recommended for: Aluminum, copper, ferrous (steel) alloys and titanium
The material composition of PCB (FR4) substrate requires an end mill that is durable enough to cut through not only the metal and resin, but also the glass fiber laminate. These tools are different than what is used just for pure aluminum or copper which conduct more heat that prematurely wears ordinary end mills. For ferrous (Fe) alloys (steel) require an even different tool type than what is used for other materials.
Printed circuit boards Solder balls Hermetic (NiCo) lids
Remove copper to expose silicon
Open areas as small as 100 x 100 μm
Consumables – Cutting Metal & Circuit Board 2-Flute End Mills – 38 mm L x 3 mm shank Ø Two-flute end mills have deeper, longer gullets for greater chip-carrying capacity and are center cutting. PCB (P) ---15-922FP0.25 15-922FP0.5 15-922FP0.7 15-922FP1.0 15-922FP1.5 15-922FP3.0
Al & Cu 15-922F0.05 15-922F0.25 15-922F0.5 15-922F0.7 15-922F1.0 15-922F1.5 15-922F3.0
Ferrous (Fe) ---15-922FS0.25 15-922FS0.5 15-922FS0.7 15-922FS1.0 15-922FS1.5 15-922FS3.0
Diameter 0.05 mm 0.25 mm 0.5 mm 0.7 mm 1 mm 1.5 mm 3 mm
Qty Pk/4 PK/4 Pk/4 Pk/4 Pk/4 Pk/4 Pk/4
Cut through circuit board material (FR4) with ease
4-Flute End Mills – 38 mm L x 3 mm shank Ø Four-flute end mills produce finer finishes and last longer than 2-flute because wear is distributed over a greater area. They also remove material more quickly and can be moved across the sample at a higher rate. PCB (P) 15-924FP0.7 15-924FP1.0 15-924FP1.5 15-924FP3.0
Al & Cu 15-924F0.7 15-924F1.0 15-924F1.5 15-924F3.0
Ferrous (Fe) 15-924FS0.7 15-924FS1.0 15-924FS1.5 15-924FS3.0
Diameter 0.7 mm 1 mm 1.5 mm 3 mm
Qty Pk/4 Pk/4 Pk/4 Pk/4
4-Flute, Long Reach – 38 mm L x 3 mm shank Ø Long-reach end mills feature cutting flutes that extend up from the tip approximately 3x the diameter of the tip to allow cutting into deep cavities. PCB (P) ---15-924FP1.0-3 ----
Al & Cu 15-924F0.7-3 15-924F1.0-3 15-924F1.5-3
Ferrous (Fe) Diameter 15-924FS0.7-3 0.7 mm 15-924FS1.0-3 1 mm 15-924FS1.5-3 1.5 mm
Qty Pk/4 Pk/4 Pk/4
Small diameter (< 3 mm) end mills provide excellent rigidity to the tip, whereas long reach end mills (right) provide greater reach to produce deeper cuts
Consumables â€“ Coarse Grinding Plated Diamond Tools Plated diamond tools feature the coarsest diamond abrasive, which is useful for bulk material removal of:
> Glass > Ceramic > Glass-Fiber Reinforced Circuit Boards > Sapphire > Mineral/Glass Filled Resins A silicon carbide dressing stick can be used to remove embedded material and extend the tool life. All tools are 38 mm in length.
Item No. 15-92CP1.0 15-92CP1.5 15-92CP3.0
Diameter 1 mm 1.5 mm 3 mm
15-92FP0.7 15-92FP1.0 15-92FP1.5 15-92FP3.0
0.7 mm 1 mm 1.5 mm 3 mm
Qty Pk/4 Pk/4 Pk/4
Pk/4 Pk/4 Pk/4 Pk/4
Consumables â€“ Precision Grinding Metal Bond Diamond Tools Metal bond diamond tools are recommended for grinding silicon and mold resins containing mineral and/or glass/silica filler. When compared with plated tools, bonded tools produce a finer surface finish and allow grinding closer to end point targets with significantly less damage. Bonded tools retain their shape and last longer than plated tools because as the bond and diamond layer wear, new diamond is exposed. As the tip wears, the geometry can be revived using the reshaping tool provided with the X-PrepÂŽ. All tools are 38 mm in length.
> Silicon > GaAs > GaN > Mold Compound (Encapsulant) > Glass > Sapphire
Item No. 15-92CMB3.0
Diameter 3 mm
15-92MMB1.0 15-92MMB1.5 15-92MMB3.0
1 mm 1.5 mm 3 mm
Pk/2 Pk/2 Pk/2
15-92FMB0.55 15-92FMB0.70 15-92FMB1.0 15-92FMB1.5 15-92FMB3.0
0.55 mm 0.7 mm 1 mm 1.5 mm 3 mm
Pk/2 Pk/2 Pk/2 Pk/2 Pk/2
15-92VFMB0.70 15-92VFMB1.0 15-92VFMB1.5 15-92VFMB3.0 15-92VFMB5.0
0.7 mm 1 mm 1.5 mm 3 mm 5 mm
Pk/2 Pk/2 Pk/2 Pk/2 Pk/2 19
Consumables – Grinding/Thinning Diamond Grinding Discs These abrasive discs are used as an alternative to bonded diamond tools for thinning silicon where higher throughput is desired on large die/substrates. Discs are secured to mounts using LOCTITE® 460 or 454 and peel off easily when worn. Item No. 15-92CGD5 15-92CGD9
Diameter 5 mm 9 mm
Abrasive Coarse Coarse
Qty Pk/100 Pk/100
5 mm 9 mm
15-92FGD3 15-92FGD5 15-92FGD9 15-92FGD12
3 mm 5 mm 9 mm 12 mm
Pk/100 Pk/100 Pk/100 Pk/100
15-92VFGD3 15-92VFGD5 15-92VFGD9 15-92VFGD12
3 mm 5 mm 9 mm 12 mm
Pk/100 Pk/100 Pk/100 Pk/100
Mounts Mounts are used in conjunction with grinding and/or polishing discs. Item No. 15-92PS12 15-92PS9 15-92PS5 15-92PS3 20
Diameter 12 mm 9 mm 5 mm 3 mm
Qty Pk/5 Pk/5 Pk/5 Pk/5
5 mm Ø
9 mm Ø
12 mm Ø
Consumables - Polishing Polishing Discs Large diameter polishing discs are used for preparing larger samples to produce smooth, mirror-like, scratch-free finishes. Each polishing disc is secured to a mount using a high performance adhesive such as LOCTITEÂŽ 460 or 454 to hold it securely in place.
Shows highly polished, mirror-like surface finish (reflection on silicon)
Item No. 180-10035 180-10034 180-10033 180-10032
Name, Diameter X-Pad, 12 mm X-Pad, 9 mm X-Pad, 5 mm X-Pad, 3 mm
Qty Pk/50 Pk/50 Pk/50 Pk/50
90-150-545 90-150-544 90-150-543
DiaMat, 12 mm DiaMat, 9 mm DiaMat, 5 mm
Pk/50 Pk/50 Pk/50
90-150-735 90-150-734 90-150-733
Final-POL, 12 mm Final-POL, 9 mm Final-POL, 5 mm
Pk/50 Pk/50 Pk/50
180-10025 180-10024 180-10023
Final A, 12 mm Final A, 9 mm Final A, 5 mm
Pk/50 Pk/50 Pk/50
180-10085 180-10084 180-10083
ChemPol, 12 mm ChemPol, 9 mm ChemPol, 5 mm
Pk/50 Pk/50 Pk/50
Consumables - Polishing Small-Diameter Polishing Tools and Accessories Small (3 mm and less) diameter polishing tools can be made by first punching a small disc from the pad, then adhering it to the polishing mounts using LOCTITE® 460 or 454. A cloth-making guide is available to all X-Prep® tool owners. Item No. 180-10910 180-10950 180-10930 180-10105 180-10960
Description, Size X-Pad II, 6” x 6” Planar Pad, 6” x 6” Final-POL, 6” x 6” Final A, 6” x 6” ChemPol, 6” x 6”
Qty Pk/4 Pk/4 Pk/4 Pk/4 Pk/4
15-92P3-D 15-92P2-D 15-92P1.5-D 15-92P1-D 15-92P0.5-D 70875A41
Disposable Punch, 3 mm Ø Disposable Punch. 2 mm Ø Disposable Punch. 1.5 mm Ø Disposable Punch, 1 mm Ø Disposable Punch, 0.5 mm Ø Cloth & Grinding Disc Punch Mat, 9” x 12”
Pk/25 Pk/25 Pk/25 Pk/25 Pk/25 Ea
15-9253 15-9252 15-9251.5 15-9251 15-9250.5
Polishing Mount, 3 mm Ø Polishing Mount, 2 mm Ø Polishing Mount, 1.5 mm Ø Polishing Mount, 1 mm Ø Polishing Mount, 0.5 mm Ø
Pk/20 Pk/20 Pk/20 Pk/20 Pk/20
Item No. 71-40045 71-40045G 22
Description LOCTITE® 460 Liquid, 20 gram bottle LOCTITE® 454 Gel, 3 gram tube
Consumables - Polishing Diamond Compound, Polycrystalline Diamond compound is used for intermediate and final polishing to remove damage/scratches after the final grinding/thinning step. Polycrystalline diamond provides the best performance and surface finish. It is recommended to be used with a lubricant for maximum performance. The water soluble formula can be easily cleaned using water. Item No. 90-21040-S 90-21035-S 90-21030-S 90-21025-S 90-21020-S 90-21015-S 90-21010-S
Description 30 μm, 18 Gram Syringe 15 μm, 18 Gram Syringe 9 μm, 18 Gram Syringe 6 μm, 18 Gram Syringe 3 μm, 18 Gram Syringe 1 μm, 18 Gram Syringe 0.5 μm, 18 Gram Syringe
Other micron sizes available. See Allied’s complete product catalog for more information.
X-Lube™ – Lubricant X-Lube™ is a solvent-free lubricant that is essential in helping maintain cooler cutting temperatures to avoid overheating the sample and reduces tool wear. It can be recycled and used several times before it needs to be disposed. It is also used with diamond compound for polishing operations.
Device/sample completely submerged without splash!
Item No. 15-92XL128 15-92XL32
Description Gallon – 128 oz. (3.8 L) Quart - 32 oz. (950 mL)
Measurement - Validation X-Prep® Vision™ - Substrate Measurement System This metrology tool enables measurement of silicon and semi-transparent substrates. It is necessary for applications that require uniform thinning to a specific target with a tolerance of +/- 3 μm or better. The X-Prep® fixture adapter is also secured to the motorized stage on the X-Prep® Vision™, ensuring the measurement/tool control coordinates remain aligned when transferred between systems. A library with over 130 materials (i.e., GaAs, InGaAs, SiC, Sapphire/Al2O3, InP, SiGe, GaN, photo-resist, etc.) is included with every system.
X-Prep® fixtures secure directly onto the stage
• Multi-point scan or single-point silicon thickness measurement • 10 microns to 1 mm thick range of measurement (15 nm to 1 mm thick when configured with #15-51000 Visible Light Spectrometer) • Motorized, automatic X/Y and Z (auto-focus) with <1s acquisition time • “Drive to Coordinate” software navigation • Viewing of either 2D plot/map or 3D graph • Software automation extendable through .NET • Stage fitted with X-Prep® fixture adapter • 100 mm x 100 mm stage travel • Data export using standard Windows methods • One (1) year warranty Item No. 15-50100 15-51000 15-50020
Description X-Prep® Vision™ 100, with 100 mm x 100 mm stage travel, 100–240V Visible Light Spectrometer and Camera CCD Camera
Measurement & Observation Measurement & Observation – How It Works IR light is focused onto a sample, and a unique signal based on the refractive index of the material is created. The return signal is analyzed by the software to produce a thickness value.
Single-point measurement display
Measuring Below 10 μm Thickness For applications requiring thinning to less than 10 μm, precise measurement is possible only by adding the visible light spectrometer accessory.
Measurement & Observation Digital Indicator Measurement Stand This apparatus is useful in measuring material removal with the X-Prep®. The large granite base of this system supports the X-Prep® fixtures, and the locating bracket is used to ensure positioning accuracy so proper measurements can be obtained. Item No. 15-9120
Description Granite Stand with Digital Indicator and X-Prep® Fixture Bracket 6" W x 8" D x 2.5" H • Height adjustable indicator position • Includes lifting lever • Metric and imperial indicator selectable • 0.001 mm (1 micron) resolution
Stemi 305 Stereomicroscope The Stemi 305 stereomicroscope is useful for sample inspection and/or making tools. Item No. Description 12-S305R Stemi 305 Stereomicroscope 12-S305R-C Stemi 305 Stereomicroscope with 0.5x C-Mount Camera Adapter • Integrated LED reflected light illumination • Free working distance of 110 mm • 8x to 40x magnification range – 5:1 zoom ratio
Electrical Voltage, AC: 115 or 230 at either 50 or 60 Hz frequency Current: 10A Watts: 1000
Air Pressure: Inlet Size: Quality:
90 PSI (~6 BAR) compressed air – no flow ¼” (~6 mm) OD tubing (push-in/tool free fitting) Class 3:4:3 – reference ISO 8573.1
Weight 210 lb. (95 kg)
Required tool dimensions Length: Shank:
38 mm (1.5”) 3 mm Ø
2376 E. Pacifica Place, Rancho Dominguez, CA 90220, www.alliedhightech.com â€“ X-PrepÂŽ Rev. G/6-2016 X-Prep is a registered trademark of Allied High Tech Products, Inc. The Allied High Tech Products logo is a trademark of Allied High Tech Products, Inc. All rights reserved. All images are the copyright property of Allied High Tech Products, Inc. and may not be used without prior written permission. Allied reserves the right to make changes to the products and specifications outlined herein, with or without notification, at their sole discretion.
Allied's X-Prep Milling/Grinding/Polishing Machine