An extreme ultraviolet (EUV) radiation source apparatus includes a collector and a target droplet generator for generating a tin (Sn) droplet. A debris collection device is disposed over a reflection surface of the collector, and at least one drip hole is located between the debris collection device and the collector. A tin bucket for collecting debris from the debris collection device is located below the at least one drip hole, and a tube or guide rod extends from the drip hole to the tin bucket.