John T. Kennedy

Terahertz local oscillator for the Microwave Limb Sounder on the Aura satellite

The Microwave Limb Sounder on the Aura satellite has a radiometer at 2.5 THz to perform global mapping of OH in the atmosphere. The OH radiometer utilizes two Schottky-diode mixers pumped by an optically pumped THz gas laser local oscillator. The laser was first turned on in space on July 22, 2004, and has performed without issue for more than 30 months. The specifications, design, and modeling of this 2.5 THz laser local oscillator are presented here, along with some of the important design validation and test results.

New enabling laser applications in advanced chip packaging

Laser processing is playing an increasing role in advanced packaging. Miniaturization is an obvious driver. As features shrink lasers can play to their core strength of creating intricate features with low damage to surrounding material. But quality is not everything and overshooting the quality goal can mean the process gets more expensive than necessary. The cost of ownership or cost per part has to work out, too. The following laser-based applications have been shown to be offer a cost advantage while simultaneously offering very high quality. They serve as examples of how advances in laser technology are helping to reduce feature size, improve quality and lower cost.