Tungsten Copper Bar for More Powerful Semiconductor Lasers

• Application: Electronics, Industrial, Medical
• Standard: JIS, GB, DIN, BS, ASTM, AISI
• Purity: 80%
• Model NO.: W90Cu10, W93Cu7, W85Cu15
• Transport Package: Wood Case
• Specification: 850X520X1060MM
• Trademark: FOTMA
• Origin: China
• Production Capacity: 100000PCS Per Year

Product Description

Tungsten Copper Bar in Laser

Lasers come in many different qualities, and carbon dioxide lasers are still used in certain specific situations. However, solid-state lasers are currently the main lasers, and semiconductor lasers are the mainstream. The "crystal" oxygen-free copper heat sink was used more than a dozen or twenty years ago. The power density was not very high, and tin was generally used as solder. Oxygen-free copper heat sinks can be used, nickel-plated instead of gold-plated, but gold-plated welding has better reliability. The tungsten copper bar structure was developed in response to the requirements of high power, high reliability, and long life.

Early lasers mostly used tungsten copper C-Mount structures, which later evolved into tungsten copper bars. Early W85Cu15, currently W90Cu10 is the main one. Later, W93Cu7 needs to be tried.
Tungsten copper bars serve as conductors, heat sinks, and chip carriers. Gallium nitride chips are sandwiched between them and soldered with gold-tin solder. Several laser modules use tungsten copper bars, ranging from a few to dozens of pieces.



In the early days, about 10 years ago, the power of laser chips was not high, and the requirements for tungsten copper bars were not high. Now the power is getting higher and higher, and the requirements for tungsten copper bar size accuracy, thermal expansion coefficient matching, thermal conductivity, and coating bonding are getting higher and higher. It is mainly reflected in: the thermal expansion coefficient is close to gallium arsenide (5.9x10-6/K), the thermal conductivity is as high as possible, diamond composite materials are already being tried, and the control of key surfaces/finish/key edges (R10 microns) and coatings (nickel, gold, platinum, and local prefabricated gold tin) is becoming more and more stringent. Ten years ago, we were the only one in China that made tungsten copper bars. Our product advantages are as follows:

1.- The tungsten copper alloy produced is almost completely dense, which is crucial for thermal conductivity, thermal expansion coefficient stability, appearance dimensional accuracy, reducing surface defects, and reducing electroplating defects (color spots).

2.- High machining accuracy: verticality 90 ± 0.5°, or 0.01 mm; flatness 0.005 mm; surface finish Ra 0.1 micron; dimensional tolerance ± 0.01 mm. Unique processing technology, the surface machining texture is invisible under a high-power microscope.

3.- Reliable electroplating quality: Two typical nickel-plated and gold-plated layers. (1) Nickel 1 micron + gold 0.3 micron. No heat treatment after nickel plating, direct gold plating. (2) Nickel 2-4 micron + gold 0.5 micron. Base nickel plating 1 micron, heat treatment at 800ºC for 10 min in hydrogen atmosphere, then thicken the nickel plating to about 3 microns, and gold plating 0.5 microns. The thickness of nickel and gold layers can be adjusted according to customer needs. We can also provide high-quality local gold-tin plating services.