Patent ID: 8216908

Claim:
A method of manufacturing an extended drain transistor, the method comprising forming a gate on a substrate; forming a first spacer on a first side wall of the gate; implanting an extended drain in a surface portion of the substrate, the extended drain is adjacent a second side wall of the gate opposing the first side wall, and the second side wall is free of the first spacer; removing the first spacer; forming a second spacer on the second side wall of the gate; implanting a source in a surface portion of the substrate adjacent the first side wall of the gate, the first side wall is free of the second spacer; implanting a drain in a surface portion of the substrate adjacent the second spacer; wherein forming the first spacer on the first side wall of the gate comprises: depositing a spacer material on the first side wall and on the second side wall of the gate; depositing a resist on the substrate, on the gate, and on the spacer material; removing the resist to expose at least a portion of the gate and the spacer material covering the second side wall of the gate while maintaining the resist on the first side wall of the gate; etching the exposed spacer material on the second side wall of the gate; wherein forming the second spacer on the second side wall of the gate comprises: depositing a new spacer material on the first side wall and on the second side wall of the gate; depositing a further resist on the substrate, on the gate, and on the new spacer material; removing the further resist to expose at least a portion of the gate and the new spacer material covering the first side wall of the gate while maintaining the further resist on the second side wall of the gate; etching the exposed new spacer material on the first side wall of the gate; and further comprising: removing the remaining portion of the further resist to expose the new spacer material on the second side wall of the gate; partially etching the exposed new spacer material on the second side wall of the gate to thereby adjust a width of the second spacer on the second side wall of the gate.