Typical application
- Wafer substrate for high-brightness LED
Selectable silicon/aluminum(Si/Al) alloy
AlSi70(Si-30%Al controlled expansion alloy);
AlSi80(Si-20%Al controlled expansion alloy).
Other applications of AlSi70 or AlSi80 alloy
- Microwave carrier for telecommunication;
- Cold plate material for high-energy solid state laser;
Photovoltaic(PV) cells.
Alternative material
- Al2O₃;
- Copper-molybdenum(Cu-Mo).
Main benefits
- CTE close to that of arsenic gallium(GaAs) and Sapphire;
High thermal conductivity;
- Thermal stability;
- Readily machining and eletroless plating(e.g.Ni/Au);
- Wafer diameter can be achieved by 300mm and polishing to 10nm Ra.
AlSi Alloys Performance Parameters
Content wt% | Density g/cm³ | CTE 25℃ ppm/℃ | Thermal Conductivity 25℃ W/mK | Tensile Strength MPa | Yield Strength MPa | Poisson’s Ratio | Elongation % | Elastic Modulus GPa |
Al-27%Si | 2.6 | 17 | 175 | 170 | 130 | 0.29 | 3.8 | 91 |
Al-42%Si | 2.55 | 13.5 | 143 | 200 | 187 | 0.29 | 1 | 105 |
Al-50%Si | 2.5 | 11.5 | 140 | 200 | 210 | 0.28 | <1 | 108 |
Si-40%Al | 2.46 | 9 | 125 | 181 | 181 | 0.27 | <1 | 121 |
Si-30%Al | 2.43 | 7.5 | 120 | 138 | 138 | 0.25 | <1 | 131 |
Si-20%Al | 2.40 | 6 | 110 | 125 | 125 | -- | -- | 132 |