Abstract: A multistage amplifying circuit includes a first amplifying circuit that either samples a first analog voltage input or amplifies a difference between the first analog voltage and a first digital voltage converted from the first analog voltage, in response to a control signal. A second amplifying circuit either samples a second analog voltage input or amplifies a difference between the second analog voltage and a second digital voltage converted from the second analog voltage, in response to the control signal. A common amplifier receives output voltages of the first amplifying circuit and the second amplifying circuit and either resets the output voltage of the first amplifying circuit and determines an output voltage by using the second amplifying circuit, or resets the output voltage of the second amplifying circuit and determines an output voltage by using the first amplifying circuit, in response to the control signal.

Abstract: A cleaning robot having an exhaust air feedback function can utilize the vacuum suction force generated by a suction motor as well as spray exhaust air onto the surface to be cleaned by circulating the air using the suction motor, thereby improving foreign material removal efficiency. The cleaning robot includes a suction unit, a suction motor for drawing in foreign materials from the surface to be cleaned, along with air, through the suction unit, a dust collector for capturing the foreign materials, so that the air is exhausted through the suction motor, and an exhaust air feedback unit for feeding the air. The cleaning robot also includes a spray nozzle unit inserted into the suction unit and placed on the leading end of the suction unit, the spray nozzle unit spraying the air fed by the exhaust air feedback unit, to the surface to be cleaned.

Abstract: A substrate cleaning apparatus includes a supporting plate supporting a substrate and a shielding unit that is disposed above the substrate to protect the substrate. A portion of the shielding unit, which is adjacent to a focal point where light for generating shock waves is focused, is switched. Therefore, the substrate cleaning apparatus prevents the concentration of plumes and residence beams, which are generated together with the shock waves, on a specific region of the shielding unit and further prevents the recontamination of the substrate by the damage of the shielding unit.

Abstract: In a method and an apparatus for cleaning a substrate using a laser beam, an inner chamber is disposed in a process chamber to define a space in which a laser-induced shock wave is generated. The laser beam is focused on a laser focus positioned in the inner chamber, and thus the laser-induced plasma shock wave is generated around the laser focus. The plasma shock wave is reflected from inner surfaces of the inner chamber and is irradiated on the substrate through a lower portion of the inner chamber. As a result, the intensity of the plasma shock wave irradiated on the substrate is increased, and thus the contaminants on the substrate may be effectively removed.