Sputtering Yields
The following table of common target materials is useful in making comparisons between deposition processes. The second column shows the maximum theoretical Density of each material. While this density has no bearing on rate, higher density targets (as close as possible to the theoretical maximum) last longer and have fewer voids or inclusions, so they provide better films.
The “Yield” data in the third column represents the number of target atoms sputtered (ejected from the target) per argon ion striking the target with a kinetic energy of 600 ev. This energy is typical for an argon plasma. Magnetron design factors such as the magnetic field strength (and process parameters such as gas composition and pressure) will affect these data, of course. But they remain useful for comparison purposes.
The “Rate” data are representative of the film deposition rate at maximum power density (i.e. about 250 w/in2, with direct cooling) and a 4″ source to substrate distance. The rates will decrease linearly with lower power levels. With all other factors unchanged, the film deposition rate will:
- Decrease by approximately 25% per inch beyond the 4″ source to substrate distance.
- Increase by approximately 35% per inch closer than the 4″ substrate distance.
| Target Material | Density (g/cc) | Yield @ 600 ev | Rate* (Ã…/sec) |
|---|---|---|---|
| Ag | 10.5 | 3.4 | 380 |
| Al | 2.7 | 1.2 | 170 |
| Al98Cu2 | 2.82 | 170 | |
| Al2O3 | 3.96 | 40 | |
| Al99Si1 | 2.66 | 160 | |
| Au | 19.31 | 2.8 | 320 |
| Be | 1.85 | 0.8 | 100 |
| B4C | 2.52 | 20 | |
| BN | 2.25 | 20 | |
| C | 2.25 | 0.2 | 20 |
| Co | 8.9 | 1.4 | 190 |
| Cr | 7.2 | 1.3 | 180 |
| Cu | 8.92 | 2.3 | 320 |
| Fe | 7.86 | 1.3 | 180 |
| Ge | 5.35 | 1.2 | 160 |
| Hf | 13.31 | 0.8 | 110 |
| In | 7.3 | 800 | |
| In2O3 | 7.18 | 20 | |
| ITO | 7.1 | 20 | |
| Ir | 22.42 | 1.2 | 135 |
| Mg | 1.74 | 1.4 | 200 |
| MgO | 3.58 | 20 | |
| Mn | 7.2 | 1.3 | 180 |
| Mo | 10.2 | 0.9 | 120 |
| MoS2 | 4.8 | 40 | |
| MoSi2 | 6.31 | 110 | |
| Nb | 8.57 | 0.6 | 80 |
| Ni | 8.9 | 1.5 | 190 |
| Ni81Fe19 | 8.8 | 110 | |
| Ni80Cr20 | 8.5 | 140 | |
| Ni93V7 | 8.6 | 100 | |
| Os | 22.48 | 0.9 | 120 |
| Pd | 12.02 | 2.4 | 270 |
| Pt | 21.45 | 1.6 | 205 |
| Re | 20.53 | 0.9 | 120 |
| Rh | 12.4 | 1.5 | 190 |
| Ru | 12.3 | 1.3 | 180 |
| Si | 2.33 | 0.5 | 80 |
| SiC | 3.22 | 50 | |
| SiO2 | 2.63 | 70 | |
| Si3N4 | 3.44 | 40 | |
| Sn | 5.75 | 800 | |
| SnO | 6.45 | 20 | |
| Ta | 16.6 | 0.6 | 85 |
| TaN | 16.3 | 40 | |
| Ta2O5 | 8.2 | 40 | |
| Th | 11.7 | 0.7 | 85 |
| Ti | 4.5 | 0.6 | 80 |
| TiN | 5.22 | 40 | |
| TiO2 | 4.26 | 40 | |
| U | 19.05 | 1 | 155 |
| V | 5.96 | 0.7 | 85 |
| W | 19.35 | 0.6 | 80 |
| W90Ti10 | 14.6 | 80 | |
| WC | 15.63 | 50 | |
| Y | 4.47 | 0.6 | 85 |
| YBCO | 5.41 | 10 | |
| Zn | 7.14 | 340 | |
| ZnO | 5.61 | 40 | |
| ZnS | 3.98 | 10 | |
| Zr | 6.49 | 0.7 | 85 |
| ZrO2 | 5.6 | 40 |
* The above rates are provided as a comparison. Specific deposition rates will vary based upon system design and process parameters.
