Method and apparatus for generating laser produced plasma

摘要

The present invention provides a method of delivering solid material at a position far enough from any surrounding solid with high enough target density without scattering debris to the environment. In the present invention, radiation is generated from plasma produced by laser irradiation on a material. This material is a cluster of particles that is composed of many fine particles bound together with a binder that vaporizes at temperature lower than melting point of fine particles. Density of particles in a particle-cluster 8 is increased by vaporizing a solvent 7 by heating a droplet 5 with the irradiation of laser 6. Solvent of a droplet occupies large fraction of the droplet in order to stabilize droplet generation. This solvent is vaporized prior to delivery to a vacuum chamber 9 for plasma generation. This vaporization helps to avoid degradation of vacuum of the chamber 9. The diameter of a particle-cluster thus condensed is several tens mum.