Radiant energy – Irradiation of objects or material – Irradiation of semiconductor devices
Reexamination Certificate
2000-03-23
2004-08-17
Berman, Jack (Department: 2881)
Radiant energy
Irradiation of objects or material
Irradiation of semiconductor devices
Reexamination Certificate
active
06777697
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a charged-particle beam exposure apparatus such as an electron beam exposure apparatus or ion beam exposure apparatus mainly used to manufacture a semiconductor integrated circuit, mask, and the like and, more particularly, to a charged-particle beam exposure apparatus for drawing a pattern using a charged-particle beam, and a device manufacturing method using the same.
BACKGROUND OF THE INVENTION
FIG. 1
is a view showing the schematic arrangement of an electron beam exposure apparatus as an example of a conventional charged-particle beam exposure apparatus. In
FIG. 1
, reference numeral
710
denotes a work chamber which incorporates an X-Y stage
712
holding a sample
711
such as a semiconductor wafer or a glass mask material. The X-Y stage
712
is driven by an X-Y stage controller
713
in the X direction (right and left with respect to the sheet surface of
FIG. 1
) and the Y direction (back and forth with respect to the sheet surface of FIG.
1
).
An electron beam optical system
720
is arranged above in the work chamber
710
. The optical system
720
is comprised of an electron gun
721
, various lenses
722
to
727
, a blanking deflector
731
, a deflector
732
for changing the beam size, a main deflector
733
for scanning a beam, a sub-deflector
734
for scanning a beam, a beam shaping aperture, and the like. The main deflector
733
positions a beam to a predetermined sub-deflection region (subfield), and the sub-deflector
734
positions a figure drawing position in the subfield. At the same time, the deflector
732
and shaping aperture control the beam shape. While the X-Y stage
712
is continuously moved in one direction, drawing processing is done for a drawing stripe region (region within a range drawable by one continuous movement of the X-Y stage
712
). Every time one continuous movement of the X-Y stage
712
ends, the X-Y stage
712
is moved stepwise in a direction perpendicular to the continuous movement direction. This processing is repeated to sequentially perform drawing processing for respective drawing stripe regions.
A main control system
740
outputs drawing control data for each stripe that is stored in a drawing control data memory
741
to a blanking controller
745
, beam shaping controller
746
, main-deflector controller
747
, and sub-deflector controller
748
. Each controller controls a control object on the basis of the drawing control data in synchronism with a sync signal from a sync signal generator
749
.
More specifically, the main-deflector controller
747
supplies a predetermined deflection signal to the main deflector
733
of the optical system
720
in synchronism with a sync signal from the sync signal generator
749
. Then, the electron beam is deflected to scan a designated subfield position. A predetermined time after the main-deflector controller
747
receives the sync signal, the main-deflector controller
747
outputs to the blanking controller
745
, beam shaping controller
746
, and sub-deflector controller
748
an enable signal representing that the electron beam is settled in the designated position to enable exposure. At the same time, the sub-deflector controller
748
receives a sync signal from the sync signal generator
749
, and supplies a predetermined sub-deflection signal to the sub-deflector
734
in synchronism with the sync signal. The beam shaping controller
746
supplies a predetermined deflection signal to the deflector
732
to control the size of the electron beam. The blanking controller
745
supplies a predetermined deflection signal to the blanking deflector
731
to control irradiation of the electron beam. Accordingly, drawing processing is done in units of subfields.
Letting a settling time be a time required for the control object of the control system to reach a target value, the settling time of an electron beam deflected by the main deflector
733
changes depending on the deflection amount. In the prior art, the maximum settling time required to settle an electron beam deflected by the main deflector
733
is regarded as an electron beam settling time in all the deflection amounts, and each controller is controlled using this settling time as a reference (fixed settling time). That is, the fixed settling time after the main-deflector controller
747
receives a sync signal, the main-deflector controller outputs to each controller an exposure enable signal representing that the electron beam is settled in a target position to enable exposure. Depending on the deflection amount of the main deflector
733
, a wasteful standby time is set to decrease the productivity of the electron beam exposure apparatus. Further, an actual exposure apparatus comprises a plurality of controllers for controlling deflection of the electron beam for respective subfield exposure processes. In addition, the settling time of an electron beam deflected under the control of each controller changes depending on a preceding state. For this reason, the longest settling time is set as a standby time. As a result, the productivity further decreases.
SUMMARY OF THE INVENTION
The present invention has been made in consideration of the above situation, and has as its object to determine a proper settling time for each operation and reduce an unnecessary standby time, thereby obtaining high throughput.
A charged-particle beam exposure apparatus according to the present invention for drawing a pattern on an object to be exposed using a charged-particle beam, comprises a plurality of driving elements for drawing the pattern on the object while scanning the object with the charged-particle beam, a plurality of driving data memories for storing a plurality of time-series driving data strings for driving said plurality of driving elements, each driving data memory sequentially supplying data forming the time-series driving data string from first data to a corresponding driving element in accordance with an operation command, and a pattern memory for storing a plurality of operation command data strings obtained by aligning operation commands and non-operation commands in time-series, the operation commands and the non-operation commands constituting each operation command data string being sequentially supplied from first operation command data to a corresponding driving data memory in accordance with a control signal supplied to the pattern memory. The charged-particle beam exposure apparatus can achieve high throughput.
The plurality of driving elements may include a plurality of types of driving elements, and/or a deflector for deflecting the charged-particle beam, and/or an irradiation controller for controlling irradiation of the charged-particle beam to the object. The irradiation controller controls whether the object is irradiated with the charged-particle beam and/or an irradiation time of the charged-particle beam to the object.
Alternatively, the plurality of driving elements may include a first deflector for deflecting the charged-particle beam and scanning a subfield of the object with the charged-particle beam, and a second deflector for deflecting the charged-particle beam and changing a subfield to be scanned.
Alternatively, the charged-particle beam exposure apparatus may further comprise a charged-particle beam source, and an electrooptic system for projecting on the object the charged-particle beam emitted by the source, and the plurality of driving elements may include a focus correction unit for correcting a focal position of the electrooptic system.
Alternatively, the charged-particle beam exposure apparatus may further comprise a source for generating a charged-particle beam, and an electrooptic system for projecting on the object the charged-particle beam emitted by the source, and the plurality of driving elements may include an astigmatism correction unit for correcting astigmatism of the electrooptic system.
Alternatively, the charged-particle beam exposure apparatus may further comprise a source for generating a charged-particle
Muraki Masato
Yui Yoshikiyo
LandOfFree
Charged-particle beam exposure apparatus and device... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Charged-particle beam exposure apparatus and device..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Charged-particle beam exposure apparatus and device... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3348514