Pace FEMTO-1000 (NANO-1000T polishing head)
Prior to the molding, the Cutting of the test vehicle is performed using an Allied Trim Saw and diamond sectioning blade. The next step is to prepare the molding, by cast mounting using two different materials (resin + hardener). This operation is followed by ultrasound phase to avoid the formation of bubbling during the hardening phase. After 24 hrs, under the room temperature the samples are removed from the plastic mold. From rough to finer grinding are accomplished using standard PSA-backed Silicon Carbide (SiC) grit papers, according to the table below table 3.2. The objective is to reach the surface of the solder joint and control the roughness of the epoxy surface. After that, the samples are mounted on the polishing pad.
The speed and the pressure are controlled using the NANO-1000T polishing head with a capacity of 6 heads at a time. Four different materials used in the polishing: (3, 1, and 0.05 µm) polycrystalline diamond suspension and 0.02 µm non-crystallizing colloidal silica polishing suspension were applied. All grinding and polishing operations were done using a Pace Technologies FEMTO-1000 (equipped with NANO-1000T polishing head) semi-automated polishing machine. A polished sample is shown in figure 3.7.
| Grinding Step number | Standard Grit Size (ANSI) | Median Particle Diameter (um) |
| 1 | 240 | 63 |
| 2 | 320 | 45.5 |
| 3 | 400 | 21.8 |
| 4 | 600 | 15.3 |
| 5 | 800 | 6.5 |
| 6 | 1200 | 2.5 |
DENTON DV-401 Carbon Coater
Prior to the SEM, the samples are coated with different materials such as Au, C ..etc. The Carbon coating technique is mainly used to inspect the specimen using the SEM (Scanning Electron Microscopy). To ensure the electrical conductivity of the specimen, the surface is coated using Carbon. First, we mount a C strand between spring holding clips. The carbon thickness is determined based on the amount of yarn filament and the working distance between the sample and the C yarn. The second step, vacuum pumping for 3 minutes followed by applying power control on the outgas position for few seconds. Finally, the flash (pulse is turned on) to burn the yarn. The specimen will be ready to be tested in the SEM. Figure 3.9 below shows the coating system used in this research study.
