An extreme ultra violet (EUV) radiation source apparatus includes a collector mirror, a target droplet generator for generating a tin (Sn) droplet, a rotatable debris collection device, one or more coils for generating an inductively coupled plasma (ICP), a gas inlet for providing a source gas for the ICP, and a chamber enclosing at least the collector mirror and the rotatable debris collection device. The gas inlet and the one or more coils are configured such that the ICP is spaced apart from the collector mirror.