Among all modern tendencies for miniaturization in semiconductor laser and optoelectronics applications, there is an area where relatively large solutions and high-power solutions are required. High-power solid-state CW lasers widely used in medical and industrial applications. High output LD power requires the improved thermal management. For applications with LD output power of 2W and higher there is a typical packaging solution based on HHL package. HHL (High Heat Load) packages were designed to provide optimal LD thermal management for high-power applications. This is the largest industrial standard package available. Windowed and fibered HHL packages are typical as a standard packaging solution for solid-state laser pumping in medical and industrial application areas like: materials processing, medical and dental therapeutics, graphic arts, eye-safe applications and others.

Laser diode inside HHL requires an appropriate temperature stabilization. The integrated thermoelectric cooler (Peltier element) is a typical solution for such applications. However, most of standard thermoelectric coolers, that are suitable for installing in HHL package, have 10-15W of max cooling capacity. Meanwhile modern semiconductor lasers output power is growing by manufacturers achievements, and the amount of heat to be dissipated grows as well. When it is required to dissipate for instance 20-30W, typical thermoelectric coolers are not suitable. Most of standard solutions with enough cooling capacity for it have 30×30mm or larger dimensions, they are not suitable for integrating in HHL package. In this case manufacturers apply external solutions for temperature stabilization like water cooling or air fans. But such solutions have limits for temperature regulating speed, size, power consumption and max cooling temperature level achieved.

Now the solutions with miniature high performance integrated thermoelectric cooling are available. The key feature is in high-performance thermoelectric coolers with high cooling capacity, which are suitable for HHL package applications by size. TEC Microsystems provides three groups of high-performance TECs for HHL package applications available: standard, enhanced and extreme. Standard solutions are based on 1MC06-126-xx and 1MC06-142-xx RMT types. for example, 1MC06-126-05 type has 28W of cooling capacity with 16×16mm2 only size. 1MC06-142-05 has elongated 12×24mm2 shape with 31W of max cooling capacity.

For applications with voltage limits of power supply there are alternate TE coolers with the same dimensions and cooling capacity, but another Imax/Umax combination from MX06 Series. If to compare with 1MC06 TECs, voltage value is reduced twice.

The enchanted solutions are based on standard 1MC06 TECs with reduced pellet height. Pellet is the BiTe element inside thermoelectric cooler. The reducing of pellet height increases the cooling capacity of thermoelectric cooler. The result of pellet increasing for 1MC06 TECs is about 60% higher cooling capacity. Thus, the max cooling capacity of 12×24mm2 1MC06-142-03 is 50W – significantly more than any typical solution, available on the market with such or similar size.

The increased cooling capacity allows to use thermoelectric coolers in that high-power LD applications, where it was not possible before, because of consumer TECs Qmax limit. Also large cooling capacity reserve allows TEC to operate with more optimal C.O.P. With the increased cooling capacity it is possible to get TEC C.O.P close or even higher than 1, which means that TEC electrical power consumption is less than pumped heat value.

Finally, the extreme cooling solution is available, based on two enhanced 1MC06-142-03 TEC installed in HHL package and connected in serial. 1MC06-142-03 type has 12×24mm dimensions. Two of them can be installed in HHL and form the operating area of 24×24mm. And the summary max cooling capacity is 100W – extreme value for lasers in HHL package.

The appropriate heatsink is required anyway to spread the pumped heat from HHL header – thermoelectric cooler operates as a heat pump. The advantage of high-performance thermoelectric coolers for LD in HHL packages is in possibility to pump large heat amounts with better C.O.P., fast and effective temperature regulating, higher cooling temperature level to achieve and expanded temperature ranges in operating mode.

TEC Microsystems GmbH provides all kinds of miniature high-performance thermoelectric coolers for high heat load applications. Thermoelectric coolers provided separately or mounted in standard HHL packages, or customer provided types. For optimization of assembling process TE cooler cold side ceramics can be with different surface solutions – blank ceramics for gluing of mounting with thermal adhesives or Au plated ceramics is the universal solution, optimal for soldering. Additionally customized Au patterns can be provided by request.