Thermocompression is a technique used for very fine applications like fine wire, for example. This technique heats up the material and compresses it the other component forming a solid-state joint, rather than a fusion weld or a reflow joint.
For very fine applications like this, a linear DC welder is ideal because of the extremely fast switching time of the weld current. There is also extremely low current ripple which is required for very fine applications where low current, high accuracy welding is required.
In addition to the Linear DC welder, a low force parallel gap head is required. Because the applications are so fine, the force applied needs to be low but very precise, so low resolution force adjustment is crucial.