Radiation imagery chemistry: process – composition – or product th – Plural exposure steps
Reexamination Certificate
2001-01-19
2003-07-01
Huff, Mark F. (Department: 1756)
Radiation imagery chemistry: process, composition, or product th
Plural exposure steps
C430S311000, C430S312000, C430S313000, C430S322000, C430S396000
Reexamination Certificate
active
06586169
ABSTRACT:
This application is a continuation of international application number PCT/EP99/03432 filed on May 19, 1999.
The present disclosure relates to the subject matter disclosed in International Application No. PCT/EP99/03432 of May 19, 1999, the entire specification of which is incorporated herein by reference. The invention relates to a lithography exposure device for producing structures extending in a surface area in a light-sensitive layer with a mounting device for the light-sensitive layer, with an exposure unit comprising at least one laser radiation source, an optical focusing means for the laser radiation associated with the laser radiation source and a screen associated with the optical focusing means and comprising a screen aperture which is elongated in a longitudinal direction and with which a radiation field can be generated in the light-sensitive layer which has in a lateral direction extending transversely to the longitudinal direction of the screen aperture an effective lateral extension which is in the order of magnitude of the wavelength of the laser radiation or smaller, with a movement unit for generating a relative movement between the optical focusing means and the mounting device and with a control for controlling the intensity and position of the radiation field relative to the light-sensitive layer in such a manner that a plurality of conversion areas can be generated in the light-sensitive layer by means of a large number of successive exposure steps and in these conversion areas the material of the light-sensitive layer is converted from an initial state into a converted end state and they together result in the structures.
A lithography exposure device of this type is known from WO 98/00760. This lithography exposure device is, however, provided only for representing structures, the extension of which is greater than that of the radiation field.
The object underlying the invention is to create a lithography exposure device, with which it is possible to produce, without masks, structures which have in at least one direction an extension which is smaller than that of one of the radiation fields used.
The object of the present invention is, in particular, to create a lithography exposure device, with which structures can be produced in the range of less than 200 nanometers extension.
This object is accomplished in accordance with the invention, by a lithography exposure device of the type described at the outset, in that with at least some of the exposure steps the control generates radiation fields with a distribution of energy which makes the action of at least two radiation fields on the same conversion area necessary in order to transfer the material of the light-sensitive layer in this area into the converted end state.
The core of the inventive solution is thus to be seen in the fact that the intensity and the distribution of the intensity of the radiation fields used is adjusted such that the effect of one radiation field in the area of action of the light-sensitive layer does not lead to a transfer of the material from the initial state into the converted end state but rather merely to a partial conversion which does not yet have the desired state. Only the action of at least a second radiation field on the same conversion area creates the possibility that in the area, in which the two radiation fields overlap, the possibility exits of a complete conversion of the material of the light-sensitive layer into the converted state insofar as the distributions of the intensity are such that the sum of the intensities in the conversion area is sufficiently large to exceed the threshold intensity for the conversion of the light-sensitive material from the initial state into the converted state.
It is thus possible, due to the use and the action of two radiation fields and the fact that the effects of the intensities have to be added together in order to exceed the threshold for the conversion of the material of the light-sensitive layer, to produce at least sections of structures, in which the extension of the sections in one direction is at the most of the same size if not smaller than the extension of one of the radiation fields in the respective direction.
In principle, it is possible to give each radiation field such a distribution of intensity that even with congruent superposition of at least two radiation fields the threshold for the conversion of the material of the light-sensitive layer from the initial state into the converted state is exceeded only in one section of the radiation fields and so the congruent superposition of two radiation fields already leads, in the long run, to a conversion area which has in at least one direction an extension which is smaller than that of the two utilized radiation fields themselves.
One particularly favorable solution does, however, provide for the two radiation fields acting on the same conversion area to be arranged so as not to be congruent but rather only partially overlapping so that a conversion area corresponding at the most to the overlapping area can already be generated due to the partial overlapping of the radiation fields and this conversion area has in the direction of the partial overlapping an extension which is smaller than that of one of the radiation fields themselves.
With the overlapping arrangement of two radiation fields it is possible to arrange the radiation fields in a parallel alignment in relation to one another, i.e. with longitudinal directions extending parallel to one another, namely such that these partially overlap.
One particularly advantageous solution provides for a first radiation field aligned in a first direction to be arranged so as to overlap with a second radiation field extending in a second direction at an angle or transversely to the first for generating a conversion area so that a complete overlapping is already excluded from the outset due to the radiation fields extending at an angle or transversely to one another and only a partial overlapping is possible, and thus the conversion area can have at the most an extension which corresponds to the overlapping area of the two radiation fields.
In this respect, it is particularly advantageous when the second radiation field extends essentially at right angles relative to the first radiation field.
A further, advantageous embodiment provides for more than two radiation fields partially overlapping with one another to be used in order to obtain a conversion area in the light-sensitive layer.
In such a case, it is preferably provided for the radiation fields contributing to a single conversion area to be arranged so as to follow one another approximately at the same angular distance.
With respect to the partial superposition of radiation fields aligned at an angle or transversely to one another it is possible to superimpose the elongated radiation fields with one another with respective end areas located in the longitudinal direction.
It is, however, particularly advantageous when the elongated radiation fields are arranged such that at least one of the radiation fields is arranged so as to overlap with the other radiation field in a central area in order to generate a single conversion area.
It is even more advantageous when the radiation fields are arranged such that their central areas partially overlap one another.
Such an arrangement of the radiation fields has the advantage that with it the positioning accuracy of the two radiation fields relative to one another can be less and that, in addition, the most intensity is customarily available in the central areas of the radiation fields and so the superposition with central areas of the radiation fields also leads summarily to the highest obtainable intensity values and thus the intensity of the laser radiation can also, for example, be utilized in an optimum manner.
With respect to the time sequence, with which the at least two radiation fields are superimposed with one another, the most varied of solutions are conceivable.
One possibility, for example, provides for
Brauch Uwe
Opower Hans
Barreca Nicole
Deutsches Zentrum fuer Luft -und Raumfahrt e.V.
Huff Mark F.
Lipsitz Barry R.
McAllister Douglas M.
LandOfFree
Lithography exposure device and lithography process does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Lithography exposure device and lithography process, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Lithography exposure device and lithography process will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3058466