Specimen preparation of extremely friable or brittle materials, such as GaAs, offer a microstructural preparation challenge. Proper microstructural preparation of these materials must minimize fracturing of the GaAs. This is accomplished by first by cutting or sectioning with fine grit / low concentration diamond blades. Oftentimes microelectronic cross sections are not encapsulated and are only mounted using a hot melt tape. If the specimens are encapsulated, a castable mounting compound such as an acrylic or an epoxy is recommended. Grinding and polishing is recommended with diamond lapping films to prevent undue damaging the GaAs substrate. Polishing is accomplished on low napped polishing cloths using hypochlorite and diamond for a CMP polishing operation.
SECTIONING
Diamond Wafering blade -fine grit / low concentration
MOUNTING
Mounting with Hot melt tape or castable mounting with Epoxy or Acrylic resins
POLISHING
Abrasive/surface |
Lubricant |
Force/ sample |
Speed |
Time |
| 15 um Diamond Lapping Film | POLYLUBE Diamond Extender | 5-10 lbs | 100/100 rpm |
Until plane |
| 9 um Diamond Lapping Film | POLYLUBE Diamond Extender | 5-10 lbs | 100/100 rpm |
2 minutes |
| 6 um Diamond Lapping Film | POLYLUBE Diamond Extender | 5-10 lbs | 100/100 rpm |
2 minutes |
| 3 um Diamond Lapping Film | POLYLUBE Diamond Extender | 5-10 lbs | 100/100 rpm |
2 minutes |
1 um DIAMAT Diamond on Atlantis polishing pad |
HOCl- (hypchlorite-bleach) |
5-10 lbs |
100/100 rpm |
1 minute |
 |
GaAs, etched with HOCl-, mag. 1000x, DIC |