ASAP-1 IPS Digital Sample Preparation System
- Wirth, Justin C
- Bradash, Mihailo Rayko
- Former user (Deleted)
- Joon Hyeong Park
2024-12-20 to 2025-01-02: Reduced Holiday Operations
Dear Birck Research Community,
The Purdue winter recess begins effective Friday afternoon December 20th and concludes Thursday morning, January 2. The university is officially closed during this time. As we have done in past years, the Birck Nanotechnology Center will remain available for research but will be unstaffed and hazardous gasses will be unavailable. Lab work may otherwise proceed, though any fume hood work must be done with someone else present in the same laboratory or cleanroom bay (the "buddy" system). Click the link above to get more detail about equipment conditions and rules.
Refer to the Material and Process Compatibility page for information on materials compatible with this tool.
Equipment Status: Set as UP, PROBLEM, or DOWN, and report the issue date (MM/DD) and a brief description. Italicized fields will be filled in by BNC Staff in response to issues. See Problem Reporting Guide for more info.
Status | UP |
Issue Date and Description | |
Estimated Fix Date and Comment | |
Responding Staff |
iLab Name: C - ASAP-1 IPS Digital Sample Preparation System
iLab Kiosk: BRK Packaging and Assembly Core
FIC: Walter Leon-Salas
Owner: Mihailo Bradash
Location: BRK 2221
Maximum Wafer Size: 4"/100 mm
Overview
Note: the following is quoted from ULTRA TEC's documentation
General Description
ASAP-1® IPS is a digital sample preparation system for the decapsulation, thinning and polishing of packaged wafer-level devices.
Drawing on ULTRA TEC’s market knowledge and long-standing leadership in electronic sample preparation, IPS is ‘device centric’ – designed to meet the non-destructive, high yield and survivability needs of micro-electronic components.
IPS’ Touch Screen OS has been designed from the ground-up to control all aspects of the sample preparation process. Advanced programming drives IPS’s deep sub-micron axes of motion. The machine vision monitor provides an unique ‘always-live’ image of the device, along with key navigational and process information.
The touch-off tool control provides Z-position at pre-defined locations and pressures – enabling package and die tilt to be corrected quickly and accurately. Tool height variations are automatically-calibrated.
Selected area preparation
"Selected Area Preparation (SAP) has long been established as a low damage machining method, with the use of relatively low spindle speeds, in conjunction with the floating head providing very low temperature rises. This is in stark contrast with high speed 'mills' which introduce excess vibration, ultrasonics, and process temperature rises -- generally requiring either a cooling bath to be in position at all time, or even a constant high flow of coolant to avoid device overheating. SAP is almost always a ‘wet process’ . However the coolant required is minimal."
The use of ULTRA TEC’s patented 'float down' head approach has enabled several hundred customers to achieve high quality polished surfaces, ready for analysis. High yields have been shown using analog ASAP-1® equipment for thinning silicon to less than 20 micron target RST. The move to higher accuracy digital systems allows for routine thinning of extremely thin substrates at even low single-digit RST’s. The move to larger flip chips mounted on PCB substrates requires inherent design for 3D sample prep. Sample Preparation developments have been driven by the industry's push for both smaller RST’s – for optimal backside imaging and attenuation – and the need for improved uniformity, to satisfy the latest analytical techniques.
• “A Straightforward Guide to the Sample Preparation of Curved & Warped IC's”; TEC Note #16, 2015 • “Backside Failure Analysis Techniques: What’s The Gain Of Silicon Getting Thinner”; Boit, Schafer et al; ESREF 2014 • “The State of the Art in Backside Sample Prep”; Jim Colvin, EDFA Vol 4, No.2, 2002 • “Packages Have Become the New IC’s”; Jim Colvin, EDFA Volume 16, Issue 4, November 2014
Specifications
- Suits all sizes of die - package, wafer and board-level
- Real Time Video Monitor with system parameter
- Touchscreen control with physical joystick & controls
- Rigidized Table Assembly and closed-loop, high-torque, motor control enhances the machining of tough and hard materials
- X, Y and Z axes all have deep sub-micron accuracy
- Accurately decaps, then thins substrate and polishes
- Patented Floating Head provides a true polishing action -- yields polishing quality & high survivability
- Intuitive menus provide a powerful, easy to use, system
- USB Flash Driveinterface for preparation recipe storage
- Short set-up and process times
- Accurate die-tilt adjustment ‘on the fly’
- Bench-top & Quiet in Operation
Z-Vertical Direction Precision | 0.04 microns (40 nanometers) |
Table Precision (X& Y Travel) | 0.2 microns (200 nanometers) |
Table Travel Amplitude | 100mm x 100mm |
Polishing Method | Patented ASAP-1 Float-down head, with Z-lock, enhanced with electronic sensors and tool patterns |
Video | Real-time machine vision with 6.5 inch video monitor. External Video Output (NTSC) |
Programming Input Method | Touchscreen with joystick and 3 physical rotary encoders |
Machine Vision | Real-time Video of overlaid with stage and process variables. |
Tilt Control | Computer-aided 2-circle tilt control, ULTRACOLLIMATOR Measurement (option) |
Force Control | 1000grams (max) with 1 gram precision. Overall accuracy +/- 10 grams |
Recipe Load & Save | USB Port, for removable flash drive (up to 2Gb) |
Z Position Touch-off Method | Mechanical Positioning with Force-feedback (option) sensors. |
X & Y Position | LASER Targeting |
Power Consumption | 300 Watts Maximum in use |
Power Requirements | Universal: 100-120VAC; 200-240VAC |
Footprint | 19 inches (480mm) Width x 25 inches (635 mm) Depth x 22 Inches (560mm) Height |
Tool Overview
Instructions | Graphics |
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Operator Controls
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Operator Input Screens
Instructions | Graphics |
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Screen Title: ASAP - 1 Initialization Screen Menu Label: NA
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Screen Title: Menu Menu Label: NA
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Screen Title: Load/Save Recipes Menu Label: Load-Save and Tool Dia
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Screen Title: Load-Save and Tool Diameter Select Menu Label: Not directly accessible from the menu
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Screen Title: Set Scan Start/Endpoints Menu Label: Start/Endpoints
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Screen Title: 3D Menu Label: 3D/Tilt
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Screen Title: Menu Label: Illumination/Cam Mode/Text
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Screen Title: Table Travel Pattern Select Menu Label: Patterns
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Screen Title: Run Menu Label: Run Process
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Screen Title: Menu Label: Z Force Feedback | |
Screen Title: Keypad Menu Label: Keypad
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Safety Precautions
This device produces visible laser radiation. To prevent injury to your eyes, never look directly into the laser.
Sample Requirements and Preparation
The Automated Selected Area Polisher (ASAP-1-IPS) is designed to thin and polish small selected areas (windows) in electronic packages and wafer-level dies. The resultant thinned component is transparent to infra-red light, thus enabling backside failure analysis to be carried out on the (front side) circuitry in the device.
Typical Applications | ||
Mechanical Decapuslation | Wafer Thinning | Failure Analysis |
Images from http://www.ultratecusa.com |
Standard Operating Procedure
Turn Power ON
Instructions | Graphics |
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Generally, turning the machine on only requires pressing the Green Power
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Sample mounting
Your sample needs to be mounted flat and rigid to the sample holder. Assuming mounting technique meets these two criteria, there is no preferred method. Below are a couple common mounting techniques used regularly.
- Bond small samples to glass slide using Crystal Bond 555-HMP, then use clamps to hold slide in place.
- Place glass slide on hot plate and heat to 80 degrees C.
- Spread a small amount of Crystal Bond 555-HMP over the area where sample will be mounted.
- Press sample firmly down onto Crystal Bond and allow assembly to cool to room temperature.
- Place assembly onto sample holder and use mechanical clamps to hold the glass slide in place.
- Bond sample directly to the sample holder using Crystal Bond 555-HMP.
- Remove the sample holder from the ASAP-1 tool.
- Place on hot plate and heat to 80 degrees C.
- Spread a small amount of Crystal Bond 555-HMP over the area where sample will be mounted.
- Press sample firmly down onto Crystal Bond and allow assembly to cool to room temperature.
- Mount sample holder back onto the ASAP-1 tool.
- Mechanical Clamps
- Using the threaded holes provided in the sample holder, mount clamps in place as needed. Two options on each side, one closer to the middle, the second further away from center accomodating a wide range of sample widths.
- The screw that threads into the clamp is used to adjust the clamp for your sample thickness. That screw needs to be adjusted so that it sticks our futher than the sample is thick resulting the the front edge of the clamp making contact with the sample.
- Tighten the slotted screw until firm.
Be sure to adjust the rear screw on the clamp appropriately based on the sample thickness. You need to have the edge exerting force on the sample top, not exerting clamping force on the glass slide / sample edge.
Be careful not to exert too much force on the sample. Clamping introduces stress on the package/wafer that can result in cracking or warping during the thinning process.
* _Proper contact angle in this image is exagerated for illustrative purposes. |
Typical Sample Mounting Technique Examples | ||
Wax Mount to Glass Slide and Mechanically Clamped | Mechanical Clamping for Decapsulation Image from http://www.ultratecusa.com | Wax Mounting Direct to Sample Holder Image from http://www.ultratecusa.com |
Selected Area Polish of Wafer Backside Process Example
Set Processing Parameters
The parameters needed for backside polishing are directly observable and will not require cross sectioning of a sample as is required with decapuslation. The tool can only polish a rectangular area with radiused corners, no other geometry is possible.
- Tool rotational speed (2000 rpm recommended starting point)
- Minimum: 1600 rpm
- Maximum: 2400 rpm
- Table speed (3.5 mm/sec recommended starting point)
- Geometry
- Start Point (μm)
- Xstart = - (Length of Area to polish in X axis-Tool Diameter) / 2
- Ystart = (Length of Area to polish in Y axis-Tool Diameter) / 2
- End Point (μm)
- Xend = (Length of Area to polish in X axis-Tool Diameter) / 2
- Yend = - (Length of Area to polish in Y axis-Tool Diameter) / 2
- Depth of polish in Z axis (μm)
- Start Point (μm)
- Processing times
- As a general rule, the more area to be thinned and polished the longer each step of the process will take, increase processing time accordingly.
Select appropriate tool size and Polishing Force
Tools can be purchased from the manufacturer at the following link:
https://www.ultratecusa.com/product/sap-tools/
Area to be Polished * Length x Width (mm2) | Tool Diameter (mm) | Suggested Polishing Force ( grams) | Processing factor (seconds/mm2) |
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up to 4 | 0.4 | 5 | 300 |
4 to 9 | 0.7 | 15 | 100 |
9 to 36 | 1.0 | 30 | 25 |
36 to 81 | 2.0 | 100 | 12 |
81 to 225 | 3.0 | 300 | 4.0 |
225 to 625 | 5.0 | 500 | 1.5 |
625 and up | 8.0 | 900 | 0.5 |
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Instructions | Graphics |
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Step 1 - Set the processing timer
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Step 2 - Set the table rastering speed (3.5 mm/s recommended)
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Step 3 - Select polishing pattern
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Step 4 - Set polishing force
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Step 5 - Set tool diameter
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Step 6 - Verify above settings are active
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Processing - Four Steps
This process recipe should be considered a guide, the procedure can be modified to meet your specific needs.
The following procedure should yield a thinned surface with no scratches in a cavity the size of your choosing.
Tool Type | Application | Coolant/Slurry | Process Time (minutes) | |
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Stage 1 | Fine Diamond | Silicon Thinning | Extender Fluid | 10 per 50 μm |
Stage 2 | XYLEM | Pre-polish | Blue diamond paste and extender fluid | 10 |
Stage 3 | XYLEM | Intermediate polish | Yellow diamond paste and extender fluid | 10 |
Stage 4 | XYBOVE | Final polish | Colloidal Silica | 5 |
* Process times are flexible and you may need to run the polishing steps longer to achieve your desired results. |
Processing Stage 1 - Silicon Thinning
Instructions | Graphics |
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Step 1 - Mount the selected diameter Fine Diamond tool into the spindle.
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Step 2 - Mount the sample to be thinned.
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Step 3 - Apply one to two drops of Extender Fluid to the area to be polished. | |
Step 4 - Gently lower the head into operating position.
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Step 5 - Define the Start point of the area to be polished.
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Step 6 - Define the End point of the area to be polished.
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Step 7 - Define the center of area to be polished as XY origin (0,0).
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Step 8 - Define the top surface of the sample as the origin, or zero,
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Step 9 - Compensate for sample tilt
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Step 10 - Start the spindle (2000 RPM recommended)
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Step 11 - Begin the thinning process
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Step 12 - Continuing to thin the sample
| Rasing the head Lowering the head |
Processing Stage 2 - Pre-polish
Instructions | Graphics |
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Step 1 - Raise the head to allow access to the sample and tool. | |
Step 2 - Thoroughly clean your sample and realign for pre-polish
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Step 3 - Mount the selected diameter Xylem tool into the spindle.
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Step 4 - Apply a small amount of Blue Diamond paste to the thinned area. | |
Step 5 - Apply one to two drops of Extender Fluid to the thinned area | |
Step 6 - Gently lower the head into operating position.
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Step 7 - Define the top surface of the sample as the origin, or zero,
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