PENTA Series Hand & Belt Grinders
The PENTA Series features hand grinders with silicon carbide rolls for precision material removal. Perfect for use with lapping films and achieving fine surface finishes.
Key Considerations
Select Appropriate Film Type
Use alumina for intermediate steps and softer materials; diamond films for harder, brittle, or high-precision applications requiring superior flatness.
Use Controlled Pressure
Even, light pressure enhances uniformity and prevents localized wear, ensuring consistent surface finishes across the entire sample.
Keep Surfaces Clean
Clean substrates and film before use to maximize performance and avoid scratching that can compromise sample quality.
Introduction
Lapping films are precision-coated abrasives that produce extremely flat surfaces across diverse materials. They're ideal for semiconductor dies, fiber optics, ceramic capacitors, optical components, and hard drive read-write heads.
These films feature a durable polyester backing (typically 3 mils) with abrasives fixed using an epoxy or adhesive binder. The uniform abrasive distribution ensures consistent surface finishes, even across varying material hardnesses.
Film Types
- Diamond lapping films: Ideal for hard, brittle materials like ceramics, silicon, and optical components. Excellent for SEM and TEM analysis with reduced relief compared to cloths.
- Silicon carbide lapping films: Provide high stock removal rates with minimal damage. Best for intermediate grinding steps and softer materials.
- Alumina lapping films: Used for final polishing due to their hardness and consistency. Effective for non-ceramic substrates and maintaining flatness in electronic packages.
Backing Types
- Plain-backed: Require a wet surface for adhesion. Offer superior flatness for precision applications.
- PSA-backed: Self-adhesive for quick installation. More convenient but may provide slightly more flexibility.
Recommended Procedures
Follow these procedures to achieve optimal results with lapping films. The process varies slightly depending on backing type and application requirements.
For Plain-Backed Lapping Films
- Wet the flat lap plate with water or a water/surfactant solution
- Place the plain-backed lapping film on the surface
- Roll out or press out any entrapped air bubbles to ensure full contact
- Apply necessary lubricant (water, diamond lapping film lube, or appropriate polishing fluid)
- Begin polishing with lower force (5-10 lbs per sample) to avoid tearing film
- Use counter-rotation at moderate speeds (100-150 RPM head/base)
- Clean specimen and film for final 10-15 seconds of polishing cycle
- Clean and dry specimens thoroughly before proceeding to next step
For PSA-Backed Lapping Films
- Ensure the lapping plate surface is clean and dry
- Place the PSA-backed lapping film on the surface, pressing firmly from center outward
- Apply necessary lubricant (water, diamond lapping film lube, or appropriate polishing fluid)
- Begin polishing with lower force (5-10 lbs per sample) to avoid tearing film
- Use counter-rotation at moderate speeds (100-150 RPM head/base)
- Clean specimen and film for final 10-15 seconds of polishing cycle
- Clean and dry specimens thoroughly before proceeding to next step
Process Parameters
Typical process parameters for lapping films:
- Force: 5-10 lbs per sample (start lower and increase gradually)
- Speed: 100-150 RPM for both head and base (counter-rotation recommended)
- Time: Continue until surface is planar and previous scratches are removed
- Lubrication: Maintain adequate lubricant flow to prevent swarf buildup and film damage
Diamond Lapping Films
| Description | Size (inches) | Catalog Number (Plain-backed) | Catalog Number (PSA backed) | Color Code |
|---|---|---|---|---|
| 0.10 um Diamond Lapping Film | Up to 12-inches | DA-01 | DAA-01 |  |
| 0.25 um Diamond Lapping Film | Up to 12-inches | DA-025 | DAA-025 |  |
| 0.50 um Diamond Lapping Film | Up to 12-inches | DA-052 | DAA-05 | |
| 1 um Diamond Lapping Film | Up to 12-inches | DA-1 | DAA-1 |  |
| 3 um Diamond Lapping Film | Up to 12-inches | DA-3 | DAA-3 |  |
| 6 um Diamond Lapping Film | Up to 12-inches | DA-6 | DAA-6 |  |
| 9 um Diamond Lapping Film | Up to 12-inches | DA-9 | DAA-9 |  |
| 15 um Diamond Lapping Film | Up to 12-inches | DA-15 | DAA-15 |  |
| 30 um Diamond Lapping Film | Up to 12-inches | DA-30 | DAA-30 |  |
Diamond Lapping Film Lubricants
| Description | Quantity (oz) | Catalog Number |
|---|---|---|
| 32 oz Diamond Lapping Film Lube | 32 | LFL-032 |
| 1 gallon Diamond Lapping Film Lube | 128 | LFL-128 |
Silicon Carbide Lapping Films
| Description | Size (inches) | Catalog Number (Plain-backed) | Catalog Number (PSA backed) |
|---|---|---|---|
| 1.0 um silicon carbide | Up to 12-inches | SIC-001PB-3 | SIC-001PSA-3 |
| 3.0 um silicon carbide | Up to 12-inches | SIC-003PB-3 | SIC-003PSA-3 |
| 5.0 um silicon carbide | Up to 12-inches | SIC-005PB-3 | SIC-005PSA-3 |
| 9.0 um silicon carbide | Up to 12-inches | SIC-009PB-3 | SIC-009PSA-3 |
| 12 um silicon carbide | Up to 12-inches | SIC-012PB-3 | SIC-012PSA-3 |
| 20 um silicon carbide | Up to 12-inches | SIC-020PB-3 | SIC-020PSA-3 |
| 30 um silicon carbide | Up to 12-inches | SIC-030PB-3 | SIC-030PSA-3 |
Alumina Lapping Films
| Description | Size (inches) | Catalog Number (Plain-backed) | Catalog Number (PSA backed) | Color Code |
|---|---|---|---|---|
| 0.05 um alumina (ALO) | Up to 12-inches | ALO-105PB-3 | ALO-105PSA-3 |  |
| 0.30 um alumina | Up to 12-inches | AL-103PB-3 | AL-103PSA-3 | |
| 1.0 um alumina | Up to 12-inches | AL-001PB-3 | AL-001PSA-3 |  |
| 3.0 um alumina | Up to 12-inches | AL-003PB-3 | AL-003PSA-3 |  |
| 5.0 um alumina | Up to 12-inches | AL-005PB-3 | AL-005PSA-3 |  |
| 9.0 um alumina | Up to 12-inches | AL-009PB-3 | AL-009PSA-3 |  |
| 12 um alumina | Up to 12-inches | AL-012PB-3 | AL-012PSA-3 |  |
| 15 um alumina | Up to 12-inches | AL-015PB-3 | AL-015SA-3 |  |
| 30 um alumina | Up to 12-inches | AL-030PB-3 | AL-030PSA-3 |  |
Troubleshooting
| Symptom | Cause | Action |
|---|---|---|
| Coarse scratching | -Swarf build-up on the lapping film | -Use a lubricant with an appropriate surfactant |
| Tearing of pad | -Sharp specimen edges | -Reduce intitial applied load so that the specimen edge does not cut the film. Gradually increase pressure during the lapping operation. -Dispense lubricant more frequently |
| Excessive relief or edge rounding | -PSA backing providing too much flexibility (resiliency) -Lapping backing plate surface is not flat |
-Use a plain backed diamond lapping film -Use a flat lapping surface |
Related Equipment
NFZ System (NANO-FEMTO-ZETA-RC)
Complete automated grinding and polishing workflow with precise control for lapping film applications and final finishing steps.
Frequently Asked Questions
Common questions about lapping films
What's the difference between diamond, SiC, and alumina lapping films?
Diamond lapping films provide the finest finish and are ideal for hard materials requiring minimal subsurface damage. Silicon carbide (SiC) films are cost-effective and suitable for most materials, offering good cutting action. Alumina films are gentler and recommended for softer materials or final polishing steps. Choose based on material hardness, desired finish quality, and cost considerations.
Should I use plain-backed or PSA-backed lapping films?
Plain-backed films require a backing plate with water to hold them in place, offering more flexibility and easier cleanup. PSA (pressure-sensitive adhesive) backed films adhere directly to the polishing surface, providing stable positioning and preventing movement during polishing. PSA films are more convenient but generate more waste. Choose plain-backed for frequent film changes and PSA for consistency and ease of use.
What grit sequence should I use for lapping films?
Start with the finest grit that achieves adequate material removal (typically 15-30 µm), then progress through finer grits (9 µm → 6 µm → 3 µm → 1 µm → 0.5 µm). Don't skip grit sizes, as this can leave scratches that are difficult to remove. For precision work, each step should remove damage from the previous step while introducing finer, more uniform scratches.
How do I prevent film tearing during use?
Film tearing typically results from excessive pressure, insufficient lubrication, or debris on the polishing surface. To prevent tearing: 1) Use light, consistent pressure (2-5 lbs per specimen), 2) Ensure adequate water or lubricant flow, 3) Clean the backing plate thoroughly before applying new film, 4) Inspect specimens for sharp edges that can catch the film, and 5) Replace worn films promptly before they tear.
Can I use lapping films without lubrication?
Lubrication is essential for lapping films. Water is the most common lubricant, providing cooling, swarf removal, and film protection. Using films dry will cause rapid film degradation, excessive heat generation, specimen damage, and poor surface finish. Always use adequate lubrication, typically water for most applications, though some materials may require specialized lubricants to prevent corrosion or chemical reactions.
How do I know when to replace a lapping film?
Replace lapping films when you notice: 1) Reduced cutting efficiency requiring longer polishing times, 2) Visible wear patterns or bald spots on the film surface, 3) Inconsistent scratch patterns on specimens, 4) The film becoming discolored or loaded with swarf that won't rinse away, or 5) Any tears or delamination. Regular replacement ensures consistent results and prevents specimen damage from worn films.