41PE Dyer A Issa and PH Key Appl Phys Lett Vol 57 1990 p 186 Equipment

Vacuum System. Figure 1 is a schematic of a PLD system. The laser radiation is focused onto a rotating target at an angle of ~45°. The substrate is mounted at 90° with respect to the target normal. Typically, the target and substrate are separated by ~5 cm, but distances as large as 12 cm have been reported (Ref 42). The vacuum system requirements vary depending on the material. Generally, oxide films are deposited in an oxygen ambient at pressures <1 torr and do not require systems with ultrahigh vacuum base pressures. Gas flow rates of 10 standard cm3/min at the desired deposition pressure can be achieved by gating the pump with the total system pressure controlled by a solenoid-activated leak valve that is controlled by a pressure transducer. At a minimum the vacuum chamber requires a pumping port, a gas inlet and pressure monitoring, a window transparent at the laser wavelength, and a viewport.

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