Tuning for optimal performance in angle control, uniformity, and energy purity

Advances in reducing the sizes of device structures and line widths place increasing demands on the accuracy of dopant placement and the control of dopant motion during activation anneals. Serial process high current ion implantation systems seek to produce beams in which the angles are controlled to high precision avoiding the angles introduced by conical structures used for holding wafers on spinning discs in batch systems. However, ion optical corrections and control of incident beam angle, dose uniformity, high throughput and energy purity often present apparently contradictory requirements in machine design. Data is presented to illustrate that tuning procedures can be used to simultaneously optimize angle purity in both x and y planes as well as control energy purity and dose uniformity.