Patent ID: 11594441

Abstract:
A method of modifying a high-resistivity substrate so that the substrate may be electrostatically clamped to a chuck is disclosed. The bottom surface is implanted with a resistivity-reducing species. In this way, resistivity of the bottom surface of the substrate may be greatly reduced. In some embodiments, to implant the bottom surface, a coating is applied to the top surface. After application of the coating, the substrate is flipped so that the front surface contacts the top surface of the chuck. The ions are then implanted into the exposed bottom surface to create the low resistivity layer. The resistivity of the low resistivity layer proximate the bottom surface after implant may be less than 1000 ohm-cm. Once the bottom surface has been implanted, the substrate may be processed conventionally. The low resistivity layer may later be removed by wafer backside thinning processes.