The field of complex plasma research evolved from the investigation of dusty plasmas. Early works dealt with the interaction of dust particles with plasmas in space. Dusty plasmas appear in space in interstellar molecular clouds, in proto-planetary disks, and - in our solar system - in cometary tails and planetary rings. Space probes, such as VOYAGER and GIOTTO, influenced this work at the beginning in the 70ies and 80ies of the 20th century. (See Pictures of dust in space.)
In 1986 H. Ikezi published a theoretical work on Coulomb crystallization in a dusty plasma.
While astrophysicists fell in love with dusty plasmas, the micro-chip industry tried to avoid dust grains inside their processing chambers with all means. In the mid-80ies of the 20th century several plasma processes were introduced in the progress of creating smaller and smaller devices on integrated circuit chips. Each single dust grain falling on the surface of a micro-chip during manufacturing will destroy it and therefore raise production costs. The scientists in industry assumed that the dust they found on the chips came from outside the hermetically sealed process chambers and they improved the technique of their clean rooms further and further (and spent more and more money on that). Nevertheless, they found almost the same amount of dust in their chambers.
Gary Selwyn of IBM solved the riddle, when pointing a laser device into a processing chamber during plasma etching. He discovered a cloud of dust floating inside the chamber (Pictures). The dust particles even grew with time from nanometer to micron-size. This means that the dust did not come from the outside but rather was a product of the plasma etching itself. The effort to prevent this dust production also gave a boost to the growing research on dusty plasmas.
History of the investigation of complex plasmas at the MPE Garching:
The story continues! (See PKE History!)
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More on the scientific background of plasma crystals...
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