摘要:
Disclosed is a vacuum valve apparatus comprising a valve head, a motor for driving the valve head, means for checking the position of the valve adapted to issue a first signal upon detecting that the valve head is moved to be within a predetermined valve-closed range, means for checking electric current adapted to issue a second signal when the driving current for the motor is increased to a predetermined value, switching means adapted to cut the driving current supply to the motor upon detecting said second signal, and means for issueing a third signal for confirming the complete closure of the valve when both of the first and the second signals are simultaneously obtained.
摘要:
A field emission electron gun according to this invention comprises a cathode for emitting electrons, an anode, a high voltage source which applies a high voltage between the cathode and the anode in order to cause emission of electrons from the cathode, a reference voltage source, voltage control means for controlling and stabilizing the output voltage of the high voltage source in response to an output voltage of the reference voltage source, means for detecting the value of an emission current from the cathode, means for delivering as an output a signal corresponding to the difference between the detected value and a desired value, and means for applying the output signal to the reference voltage source through a switch. The reference voltage source includes means which, when the switch is in the closed state, controls the output voltage of the reference voltage source in response to the difference output signal, and means which, when the switch is in the open state, continues to hold the output voltage value of the reference voltage source immediately before the opening of the switch as it is. The electron gun of this invention accordingly conducts when the switch is in the closed state, a constant current operation which makes constant the emission current from the cathode, and conducts when the switch is in the open state, a constant voltage operation which makes constant the voltage applied between the cathode and the anode.
摘要:
In order to provide a high-speed and high accuracy cell projection exposure apparatus which increases a pattern projection number extremely, a plurality of stencil masks mounting a transferal aperture and a transmission aperture are provided and are positioned by a drive stage, the electron beam passes through a transmission aperture of other stencil masks while selecting the aperture on a stencil mask with a beam deflection device, the transmission aperture is provided for a mask transfer direction in succession, the stencil mask is moved while being transmitted with the beam, and other stencil mask transfer is executed when specified stencil mask aperture group is exposed. These operations are repeated so that all exposure processes are performed.
摘要:
An elevator adjusting apparatus for adjusting a brake torque produced by a brake for braking travel of an elevator cage includes a brake torque adjustment mode setting unit for setting an adjustment mode for the brake torque, a cage position recognizing unit for recognizing a cage position, a cage speed detecting unit for detecting a cage speed, a brake actuation command generating unit for reissuing a brake actuation command generating unit for issuing a brake actuation command when the brake torque adjustment mode is set by the brake torque adjustment mode setting unit and the cage position recognizing unit recognizes that the cage position has reached a predetermined position of a lift passage, a brake control unit for actuating the brake in response to the brake actuation command issued from the brake actuation command generating unit, and a brake torque calculating unit for calculating the brake torque based on the cage speed detected by the cage speed detecting unit during the brake actuation. With the apparatus, the brake torque can be adjusted simply accurately and efficiently without using any weights.
摘要:
A column section is disposed within a thermostatic chamber within a clean room, a section for analog controlling each portion of the column section is disposed within the clean room and outside of the thermostatic chamber, and a section for digital controlling the analog control section is disposed outside of the clean room.
摘要:
In order to provide a high-speed and high accuracy cell projection exposure apparatus which increases a pattern projection number extremely, a plurality of stencil masks mounting a transferal aperture and a transmission aperture are provided and are positioned by a drive stage, the electron beam passes through a transmission aperture of other stencil masks while selecting the aperture on a stencil mask with a beam deflection device, the transmission aperture is provided for a mask transfer direction in succession, the stencil mask is moved while being transmitted with the beam, and other stencil mask transfer is executed when specified stencil mask aperture group is exposed. These operations are repeated so that all exposure processes are performed.
摘要:
In a semiconductor circuit device fabricating process in which a reduction image projection exposure apparatus and an electron beam exposure apparatus are in a mixed use in its exposure process, pattern position shift errors for each exposure apparatus are measured and corrected at the time of drawing by means of an electron beam drawing apparatus, thereby enhancing the alignment accuracy.First, a pattern for measuring position shifts is exposed using a stepper and the electron beam drawing apparatus. Then, the position shift errors are measured using an identical coordinate position measuring device. Accidental errors have been mixed in the measurement result at this time. On account of this, measurement data at a certain point are smoothed by taking a summation average with data on the periphery thereof, thus decreasing influences of the accidental errors. Moreover, by inverting positive or negative signs of the data on the position shift errors, the data are made into correction data. Then, the correction data are stored. When an exposure is performed by the electron beam drawing apparatus with the pattern exposed by the stepper as a reference, the correction data for the two apparatuses are transferred to the electron beam drawing apparatus, the two data are added to detected mark positions, and at positions after the addition, pattern position shifts within a wafer surface are determined. At the time of exposure, the exposure is performed at positions obtained by subtracting the correction data from the determined pattern position shifts. This method makes it possible to correct both position shift errors within the wafer surface due to the stepper and position shift errors due to the electron beam drawing apparatus, thus allowing the alignment accuracy to be enhanced. Also, this result makes it possible to enhance yield for products in the fabricating process.
摘要:
A charged particle beam microprobe apparatus capable of accurately determining the three-dimensional structure of a surface is disclosed in which a detection system including at least a pair of detectors disposed symmetrically with respect to the optical axis of an charged particle beam generating instrument is used for obtaining an image signal from a surface scanned with a charged particle beam, the image signal obtained by difference detection in the detection system is compared with a pair of variable reference levels opposite in polarity to each other, to be converted into positive and negative rectangular wave signals, and information on whether the scanned surface slopes upward or downward when viewed from the detection system and information on the gradient of the scanned surface are obtained from the polarity and pulse width of each of the positive and negative rectangular wave signals, respectively, to determine the three-dimensional structure of the scanned surface. That is, the charged particle beam apparatus does not utilize a phenomenon that the coefficient of backscattered electrons is proportional to the angle of slope of a primary beam impinging surface, and hence can use secondary electron suitable for forming a high resolution scanned image.
摘要:
A charged particle apparatus wherein a charged particle beam irradiates an object to be observed and secondary emissions such as secondary electrons thus emitted from a surface layer of the object are detected. A signal indicative of the detected secondary emissions is applied to a control grid of a cathode ray tube to modulate an electron beam irradiating a fluorescent screen thereof. A detector detects the electron beam intensity of the cathode ray tube and minimum and maximum or peak values of the detected electron beam intensity are compared with predetermined reference signals to obtain deviation signals indicative of the difference therebetween. The signal applied to the control grid of the cathode ray tube is controlled in accordance with the deviation signals.
摘要:
A d.c. high voltage power source comprising: a d.c. high voltage generator; a voltage divider for detecting an output voltage of said generator, which is connected between the high voltage output terminal of said generator and ground potential; an error amplifier, one input terminal of said error amplifier being connected to the voltage dividing point of said voltage divider; a reference voltage source connected between the other input terminal of said error amplifier and ground potential; control means for stabilizing said output voltage of said generator by the output of said error amplifier so as to maintain said output of said error amplifier substantially equal to zero; an ammeter connected between the low voltage output terminal of said generator and ground potential; a resistor connected between the non-grounded terminal of said reference voltage source and said low voltage output terminal of said generator, the resistance value of said resistor being equal to that of the resistance to ground of said voltage dividing point of said voltage divider.