Diode laser bar mounted on a copper heat-sink
View Patent ↗A diode-laser bar package includes a water cooled metal heat-sink. An electrical-insulator-plate is bonded to the heat-sink with a soft solder. A metal sub-mount and a first electrode are bonded, spaced apart, on the electrical-insulator-plate. A solder-bridge fills the space between the first electrode and the sub-mount. A diode-laser bar is bonded to the sub-mount. A second electrode is bonded to the first electrode with an electrically insulating bond. Electrical connection between the second electrode and the diode-laser bar is made by a plurality of wire-bond electrical leads.
1. Laser apparatus, comprising
a metal heat-sink;
an electrical-insulator-plate bonded to the heat-sink with a soft solder;
a metal sub-mount and a first electrode bonded, spaced apart, on the electrical-insulator-plate using a hard solder, with that hard solder filling the space between the first electrode and the sub-mount;
a diode-laser bar bonded to the sub-mount with a hard solder;
a second electrode bonded to the first electrode and insulated therefrom by an epoxy bond; and
a plurality of wire-bond electrical connections between the second electrode and the diode-laser bar.
2. The apparatus of claim 1 , wherein the heat sink is a water-cooled heat sink having a plurality of cooling channels forming a water cooling circuit therein.
3. The apparatus of claim 2 , wherein the cooling channels have as minimum cross-section dimension of about 0.3 millimeters.
4. The apparatus of claim 1 , wherein the electrical-insulator-plate is a beryllium oxide plate.
5. The apparatus of claim 1 , wherein the sub-mount is made from one of a copper-tungsten alloy and a copper-tungsten composite.
6. The apparatus of claim 1 , wherein the diode-laser bar has a gallium arsenide substrate.
7. The apparatus of claim 1 , wherein the first electrode is made from a fusion-bonded assembly of copper and molybdenum sheets.
8. The apparatus of claim 1 , wherein the hard solder is a hard solder selected from the group of hard solders consisting of gold-tin solder, gold-silicon solder, and gold-germanium solder.
9. The apparatus of claim 8 , wherein the hard solder is a gold-tin solder.
10. The apparatus of claim 1 , wherein the soft solder is a soft solder is indium or an alloy thereof.
11. The apparatus of claim 1 , wherein the soft solder is one of a tin-silver solder and a tin-silver-copper solder.
12. The apparatus of claim 1 , wherein the epoxy bond is filled with particles of electrically insulating material.
13. The apparatus of claim 12 , wherein the particles of electrically insulating material are glass spheres.
14. Laser apparatus, comprising
a copper heat-sink;
a beryllium oxide electrical-insulator-plate bonded to the heat-sink with a soft solder;
a copper tungsten sub-mount and a first electrode bonded, spaced apart, on the electrical-insulator-plate using a hard solder, with that hard solder filling the space between the first electrode and the sub-mount;
a diode-laser bar on a gallium arsenide substrate bonded to the sub-mount with a hard solder;
a second electrode formed from a copper-molybdenum-copper composite bonded to the first electrode and insulated therefrom by a glass-filled epoxy bond; and
a plurality of wire-bond electrical connections between the second electrode and the diode-laser bar.
15. The apparatus of claim 14 , wherein the heat sink is a water-cooled heat sink having a plurality of cooling channels forming a water-cooling circuit therein.
16. The apparatus of claim 15 , wherein the cooling channels have as minimum cross-section dimension of about 0.3 millimeters.
17. The apparatus of claim 14 , wherein the hard solder is a hard solder selected from the group of hard solders consisting of gold-tin solder, gold-silicon solder, and gold-germanium solder.
18. The apparatus of claim 17 , wherein the hard solder is a gold-tin solder.
19. The apparatus of claim 14 , wherein the soft solder is indium or an alloy thereof.
20. The apparatus of claim 14 , wherein the soft solder is one of a tin-silver solder and a tin-silver-copper solder.