Patent ID: 6514840
Filing Date: 2003-02-04
Classification: H01L

Abstract:
A method for local activation comprising the steps of:providing a substrate having a first section and a second section segregated from the first section, wherein the first section contains a first doped region which includes a first dopant species and the second section contains a second doped region which includes a second dopant species; depositing a layer of oxide on the substrate; forming a reflective mask on the layer of oxide and over the first doped region and over the second doped region of the substrate, wherein the mask comprises a semi-transparent reflective material selected from the group consisting of aluminum, tungsten, copper and gold and has a first thickness over the first doped region and a second thickness different from the first thickness over the second doped region; and simultaneously activating the first dopant species in the first doped region by a first amount and the second dopant species in the second doped region by a second amount, wherein the second amount is different from the first amount, and further wherein heat energy is transmitted using a laser through the reflective mask to the first doped region and through the reflective mask to the second doped region.