JPH0770457B2 - X-ray exposure method and X-ray generation source used therefor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an X-ray exposure method and an X-ray generation source used for the same, and particularly to the use of X-rays as in an X-ray lithography apparatus for manufacturing LSI. The present invention relates to an X-ray exposure method suitable for forming a fine pattern on a semiconductor substrate and an X-ray generation source used therefor.

[Conventional technology]

In recent years, in order to manufacture higher performance semiconductor integrated circuits,
There is an increasing demand for forming a fine pattern having a dimension of 0.5 μm or less on a semiconductor substrate. X-ray (mainly 4-13
The X-ray exposure method, which is a pattern transfer technology using (Å soft X-rays), has extremely high accuracy of the transferred pattern, and is considered to be a powerful technology particularly in submicron pattern formation.

By the way, in order to carry out the X-ray exposure method, a high output and stable X
Requires a line generator. Therefore, recently, an X-ray generator using discharge plasma as an X-ray source has been studied. As shown in FIG. 4, this device discharges the electric charge of the capacitor 2 charged by the high-voltage power supply 1 between the pair of electrodes 3 and 4 to generate discharge plasma between the electrodes 3 and 4, and the energy generated in the plasma. The X-ray emitted by the transition is used. In addition, 5 in FIG. 4 shows a trigger electrode.

As such a conventional technique, for example, JP-A-58-1880
No. 40 publication.

[Problems to be solved by the invention]

The above-mentioned conventional technology has a problem that no consideration is given to control of energy transition in plasma, and only weak X-ray output is obtained. That is, to explain the X-ray generation mechanism, an atom consists of an atomic nucleus and electrons that orbit around it with a certain energy level.
When the kinetic energy of the incident electron becomes larger than the binding energy of the electron, the electron is knocked out of its shell (photoelectric effect). The electron in the outer orbit enters the vacant seat, and the energy difference held by the electron is emitted as X-ray. The situation is shown in FIG. High-energy electrons are spontaneously emitted, the transitions are accidental, and X-rays are emitted irregularly. As described above, since the energy transfer of spontaneous emission is used, it is difficult to control.

The present invention has been made in view of the above points, and an object of the present invention is to provide an X-ray exposure method capable of obtaining high-intensity X-ray output and improving throughput in X-ray exposure, and an XS-ray used therefor. To provide the source.

[Means for solving problems]

In the present invention, in order to achieve the above object, when a fine pattern is formed on a semiconductor substrate by utilizing X-rays from an X-ray generation source, the discharge plasma generated between a pair of electrodes facing each other The generated X-rays are incident on the plasma generated between the pair of electrodes in the excited state, and the X-rays induced by the X-rays are sequentially guided to the plasma between the pair of electrodes adjacent to each other to be induced and emitted. An X-ray exposure method of exposing an X-ray laser on the semiconductor substrate, and an X-ray generation source for generating X-rays for forming a fine pattern on the semiconductor substrate, wherein the X-ray generation source is a vacuum. A container, a pair of electrodes provided on the vacuum container in a plurality of one-to-one straight lines, one of which is supported by the vacuum container through an insulator, and a pair of electrodes which covers the pair of electrodes and a pair of electrodes. Electrically connected to the other electrode of A conductive path supported by an electric vacuum container via an insulator and having an opening portion for guiding X-rays generated between the pair of electrodes between the pair of adjacent electrodes; and the pair of electrodes. It is characterized in that it is an X-ray generation source for X-ray exposure, which is provided with a high voltage applying means for generating a discharge therebetween.

[Action]

The principle is shown in FIG. When an incident X-ray acts on an atom in an excited state, the same frequency phase in the same direction as the incident X-ray,
Further, it utilizes a phenomenon in which X-rays having the same polarizability are stimulated and emitted, and emitted in proportion to the intensity of incident X-rays.
In an X-ray laser that produces this phenomenon, a plurality of X-ray generation units are arranged in a straight line, and the excited state is formed by high-speed large-current discharge. At this time, when X-rays enter, high-intensity X-ray output can be obtained by stimulated emission.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. Here, the same numbers are attached to the same components as those in the conventional example of FIG. Opposing electrode pairs 31, 41, 32, 42, ... 36, 46 are provided in the vacuum vessel 6 via an insulator 15, and the electrodes 41, 42, ... 46 are cylindrical conductive paths 81, 82 ,. Is joined to. (Second
The figure shows the external appearance of one electrode pair. 36 are connected to the capacitor 2 via one of the electrodes 31, 32, ... 36 passing through X-rays and the trigger electrode 5, and one of the conductive paths 81, 82 ,. The discharge time control of the trigger electrode 5 is adjusted by the trigger time controller 7. An X-ray extraction window 10 is installed below the vacuum container 6 in the drawing.

In the generation of X-rays, the trigger electrode 5 is actuated by the electric charge of the capacitor 2 charged by the high voltage power source 1, whereby the electrode pair 31 and 41, 32 and 42, ... 36. Discharge between 46. As a result, discharge plasma is formed between the electrodes, and the atoms in the plasma are excited. Some of the X-rays generated from the spot plasma between electrodes 31 and 41 are electrodes.
It becomes an incident X-ray between 32 and 42 and induces the stimulated emission phenomenon,
X-rays are generated in the same direction as the incident X-rays. Sequential electrode pair 33 ・
Stimulated emission occurs between 43, between 34 and 44, ... and between 36 and 46, and X-ray 9 is generated. In order to transfer a fine pattern, the generated X-ray 9
Is taken out through the X-ray extraction window 10 to the exposure section. Support 11
The pattern of the mask 12 supported by the is transferred onto the silicon wafer 13 on the aligner 14. As described above, since the X-ray laser utilizing the stimulated emission phenomenon is used as the light source for X-ray exposure, high-intensity X-ray output can be obtained. Even if the incident X-ray generator for stimulated emission is generated from any of the electrode pairs shown in FIG. 1, a high-intensity X-ray output can be similarly obtained.

FIG. 3 shows another invention, in which a gas puff type is applied to the electrode pair. Each electrode pair 31,41,32,42,33,43,34,44
Are arranged in a straight line, and an opening which is a passage for X-rays is provided at the center of each electrode. A gas blowing hole 18 is provided inside each of the electrodes 31, 32, 33, 34. When generating X-rays, the gas 19 is first blown out between the electrodes from the gas introduction pipe 17. After a certain delay time, the trigger electrode 5 is activated to start discharging. The gas between the electrodes becomes a high-temperature, high-density plasma due to the magnetic pinch effect of the current and forms an excited state. At this time, when X-rays enter each plasma, the X-rays that have been stimulated and emitted are amplified and generate X-rays 9. The present invention also has the effect of generating high-intensity X-rays, as in FIG.

〔The invention's effect〕

According to the X-ray exposure method of the present invention described above and the X-ray generation source used for the method, the X-rays generated from the X-ray generation source are used to face each other when the fine pattern is formed on the semiconductor substrate. The X-rays generated from the discharge plasma generated between the pair of electrodes are incident on the plasma generated between the pair of adjacent electrodes in the excited state, and the X-rays induced thereby are sequentially generated between the pair of adjacent electrodes. X-ray exposure method for exposing and exposing an X-ray laser formed on the semiconductor substrate by inducing and inducing the above plasma to stimulate emission, and an X-ray generation source for generating X-rays for forming a fine pattern on the semiconductor substrate. The X-ray generation source includes a vacuum container, and a pair of electrodes which are provided in a plurality of one-to-one straight lines in the vacuum container and one of which is supported by the vacuum container via an insulator and which face each other. , Covering the pair of electrodes A vacuum chamber electrically connected to the other electrode of the pair of electrodes and having an opening for guiding X-rays generated between the pair of electrodes between the pair of adjacent electrodes. The X-ray generation source for X-ray exposure is provided with a high-voltage applying unit for generating a discharge between the pair of electrodes and a conductive path supported by the X-ray of high brightness. There is an effect that a line output is obtained and the throughput in X-ray exposure is improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an X-ray generation source for X-ray exposure of the present invention, FIG. 2 is a perspective view of an electrode portion adopted in the embodiment of FIG. 1, and FIG. FIG. 4 is a sectional view showing another embodiment of the present invention, FIG. 4 is a schematic configuration diagram showing a conventional X-ray generation source,
FIG. 5 is a diagram for explaining the principle of the conventional configuration,
FIG. 6 is a diagram for explaining the principle of the configuration of the present invention. 1 ... High-voltage power supply, 2 ... Capacitors 3,4,31,3
2, 33, 34, 35, 36, 41, 42, 43, 44, 45, 46 ... Electrode, 5 ... Trigger electrode, 6 ... Vacuum container, 7 ... Trigger time controller, 9 ... X-ray , 10 …… X-ray extraction window, 11
…… Support, 12 …… Mask, 13 …… Wafer, 14 …… Aligner, 15 …… Insulator, 16 …… Opening part, 17 …… Gas introduction pipe, 18 …… Gas blowing hole, 19 …… Gas, 81, 82, 8
3, 84, 85, 86 ... Conductive path.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Kurosawa 4026 Kuji Town, Hitachi City, Hitachi, Ibaraki Prefecture Hitachi Research Laboratory, Hiritsu Manufacturing Co., Ltd. (56) Reference JP-A-56-111223 (JP, A) JP-A-60 -7130 (JP, A) JP 62-273728 (JP, A) JP 62-273727 (JP, A)

Claims (2)

[Claims] 1. An X-ray exposure method for forming a fine pattern on a semiconductor substrate using X-rays from an X-ray generation source, wherein X generated from discharge plasma generated between a pair of electrodes facing each other. X-ray laser formed by injecting X-rays into plasma generated between a pair of adjacent electrodes in an excited state and sequentially guiding the X-rays induced thereby to plasma between the pair of adjacent electrodes to induce emission. An X-ray exposure method, which comprises exposing the substrate to the semiconductor substrate to perform exposure. 2. An X for forming a fine pattern on a semiconductor substrate.
An X-ray generation source for generating a line, wherein the X-ray generation source is provided on a vacuum container and a plurality of one-to-one lines in the vacuum container, and one of the X-ray generation source is supported by the vacuum container via an insulator. A pair of electrodes facing each other, and a pair of electrodes that cover the pair of electrodes and are electrically connected to the other electrode of the pair of electrodes and that generate X-rays between the pair of electrodes. And a high-voltage applying means for generating a discharge between the pair of electrodes, and a conductive path having an opening portion that leads to the electric path supported by the vacuum container via an insulator. X-ray generation source for X-ray exposure.