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[[Image:expsetup.png|center|thumb|400px|Figure: Illustration of the experimental setup used to ablate diamond using a UV excimer laser at the University of Connecticut.]]

[[Image:expsetup.png|center|thumb|400px|Figure: Illustration of the experimental setup used to ablate diamond using a UV excimer laser at the University of Connecticut.]]

Laser ablation will be used to thin the diamond chip to the precise thickness required for the radiator. An older excimer laser offered by a local AMO group will be converted from a XeCl 308 nm beam to the required ArF 193 nm beam. Although the system was last used 10 years ago, it was left in a fully functioning state and was properly flushed upon decomposition. There may also be another unused excimer laser that can be used for parts in case any repair is needed. I have included a link to my current [http://zeus.phys.uconn.edu/wiki/index.php/Pratt Lab Journal] which I plan to update bi weekly.

A research group at Brookhaven National Laboratory ([https://zeus.phys.uconn.edu/halld/diamonds/BNLdev-1-2009/smedley-1-2009_2.pdf BNL]) published results using a focused high-power UV laser to mill diamond via a process known as ablation. Lasers with wavelengths above the band gap of diamond (213 nm) [?] can excite electrons between the diamonds carbon atoms from a bound state to an ionized state. The top 100 nm of the diamond surface at the focal spot is instantly vaporized, emitting a plume of carbon-based plasma normal to the surface of the diamond crystal. By scanning the diamond across the focal spot, a sequence of overlapping spots is built up that results in uniformly milling the sample surface. The short duration (10 ns) and short absorption length (50 nm) of the laser pulse ensure that the pulse energy is absorbed in the upper 100 nm of the diamond and does not result in deep energy deposition in the bulk of the crystal. Most importantly, this technique allows the diamond to be thinned deferentially, creating a central window of 20 microns thickness while retaining the full thickness around the edges for stiffness and support. This would never be possible with an abrasive technique. The laser ablation technique on diamond was developed extensively here at UConn by the author, using a Lambda Physik EMG 101 excimer laser operating at a wavelength of 193 nm as the light source. An XYZ computer controlled stage was constructed to sweep the diamond (under a vacuum of 600 mtorr) across the laser focus. The bulk diamond crystal before machining is typically of size 7.2 x 7.2 x 0.250 mm<\math>^3<\math> . A series of laser pulses was applied

==Excimer Laser==

==Excimer Laser==