Abstract: Embodiments of the invention generally provide an electron beam substrate processing system. In one embodiment, the present invention provides an electron beam substrate processing system where a spindle shaft used to rotate substrates during processing includes at least one optical encoder wheel assembly. The optical encoder wheel assembly is configured to provide rotational speed data signal to a rotational speed control system and a pattern generation clock circuit configured to a provide an angular pattern generator clock signal and to a pattern generator circuit. The pattern generation circuit is configured to control modulation of an electron beam used for substrate processing. In one aspect of the present invention, while the spindle shaft is rotated at a constant linear velocity, the pattern generation circuit controls the modulation of an electron beam such that written mark lengths are sized to be about constant in angular dimension.

Abstract: An apparatus for and method of writing multiple radial locations during a single rotation by deflection and modulation of a recording beam, employs an electron beam with a width that is narrower than a radial width of the exposure pattern. Instead of employing multiple exposure passes, with each offset from the other by a certain radial distance, the apparatus performs the write of the pattern in a single pass. During this single pass, controlled by a single rotation of the turntable on which the disk recording medium is located, the electron beam is deflected in a radial direction by a required amount and modulated in synchronization with the radial deflection. This synchronization of the beam modulation with the beam deflection allows a plurality of tracks to be written or exposed in a single pass.

Abstract: A rotating recording device, such as an electron beam recorder, is provided with a dual encoder arrangement. A first encoder is employed as a spindle motor controller and located at a first end of a spindle. A second encoder is mounted at a turntable adjacent to a recording surface and used as a position, velocity or clock source for recording the pattern on the substrate. Eccentricity of the mounting of the second encoder is measured against the more accurately mounted spindle control encoder and compensated by a digital clock generating system using a digital phase locked loop.

Abstract: Embodiments of the invention generally provide an electron beam substrate processing system. In one embodiment, the present invention provides an electron beam substrate processing system where a spindle shaft used to rotate substrates during processing includes two encoder wheels. One encoder wheel is configured to provide a rotational speed data signal to a rotational speed control system. Another encoder wheel is configured to provide a pattern generator clock signal at a higher frequency than the rotational speed data signal to a pattern generator. In one embodiment of the present invention, at least one of the encoder wheels is positioned adjacent the substrate to minimize torsional and differential movements between the at least one encoder wheel and the substrate.

Abstract: Embodiments of the invention generally provide an electron beam substrate processing system. In one embodiment, the present invention provides an electron beam substrate processing system where a spindle shaft used to rotate substrates during processing includes at least one optical encoder wheel assembly. The optical encoder wheel assembly is configured to provide rotational speed data signal to a rotational speed control system and a pattern generation clock circuit configured to a provide a corrected pattern generator clock signal to a pattern generator circuit. The pattern generation circuit is used to control modulation of an electron beam used for substrate processing. In one aspect of the present invention, repeatable deviations of the rotational speed are measured and processed during substrate processing to correct for such repeatable deviations to increase substrate pattern writing accuracy.

Abstract: Embodiments of the invention generally provide an electron beam substrate processing system. In one embodiment, the present invention provides an electron beam substrate processing system where a spindle shaft used to rotate substrates during processing includes at least one optical encoder wheel assembly. The optical encoder wheel assembly is configured to provide rotational speed data signal to a rotational speed control system and a pattern generation clock circuit configured to a provide a corrected pattern generator clock signal to a pattern generator circuit. The pattern generation circuit is used to control modulation of an electron beam used for substrate processing. In one aspect of the present invention, repeatable deviations of the rotational speed are measured and processed during substrate processing to correct for such repeatable deviations to increase substrate pattern writing accuracy.

Abstract: Embodiments of the invention generally provide an electron beam substrate processing system. In one embodiment, the present invention provides an electron beam substrate processing system where a spindle shaft used to rotate substrates during processing includes at least one optical encoder wheel assembly. The optical encoder wheel assembly is configured to provide rotational speed data signal to a rotational speed control system and a pattern generation clock circuit configured to a provide an angular pattern generator clock signal and to a pattern generator circuit. The pattern generation circuit is configured to control modulation of an electron beam used for substrate processing. In one aspect of the present invention, while the spindle shaft is rotated at a constant linear velocity, the pattern generation circuit controls the modulation of an electron beam such that written mark lengths are sized to be about constant in angular dimension.