Excimer Laser Beam Analyzer Based on CVD Diamond

1‐D and 2‐D detector arrays have been realized on CVD‐diamond. The relatively high resistivity of diamond in the dark allowed the fabrication of photoconductive “sandwich” strip (1D) or pixel (2D) detectors: a semitransparent light‐receiving back‐side contact was used for detector biasing. Cross‐talk between pixels was limited by using intermediate guard contacts connected at the same ground potential of the pixels. Each pixel photocurrent was conditioned by a read‐out electronics composed by a high sensitive integrator and a Σ‐Δ ADC converter. The overall 500 μs conversion time allowed a data acquisition rate up to 2 kSPS. The measured fast photoresponse of the samples in the ns time regime suggests to use the proposed devices for fine tuning feedback of high‐power pulsed‐laser cavities, whereas solar‐blindness guarantees high performance in UV beam diagnostics also under high intensity background illumination. Offering unique properties in terms of thermal conductivity and visible‐light transparency, diamond represents one of the most suitable candidate for the detection of high‐power UV laser emission. The technology of laser beam profiling is evolving with the increase of excimer lasers applications that span from laser‐cutting to VLSI and MEMS technologies. Indeed, to improve emission performances, fine tuning of the laser cavity is required. In such a view, the development of a beam‐profiler, able to work in real‐time between each laser pulse, is mandatory.