JP6982992B2 - Conductive contact needle - Google Patents

Description

The present invention relates to a conduction contact needle, and relates to, for example, a contact needle for an earth pin that prevents the substrate from being charged when an electron beam is applied to the substrate.

Lithography technology, which is responsible for the progress of miniaturization of semiconductor devices, is the only extremely important process for generating patterns in the semiconductor manufacturing process. In recent years, with the increasing integration of LSIs, the circuit line width required for semiconductor devices has been miniaturized year by year. In order to form a desired circuit pattern on these semiconductor devices, a high-precision original image pattern (also referred to as a reticle or a mask) is required. Here, the electron beam (EB: Electron beam) drawing technique has essentially excellent resolution and is used for producing a high-precision original image pattern.

For example, a circuit pattern is drawn by an electron beam on a mask blank in which a Cr film (light-shielding film) and a resist film are sequentially formed on a quartz glass substrate, and after development and etching of the light-shielding film, a light-shielding film pattern (mask) is drawn. By forming the pattern), a mask substrate for exposure is manufactured. Here, when the pattern is drawn by the electron beam drawing apparatus, the resist film is charged by the irradiation of the electron beam. Due to the charging of the resist film, the trajectory of the subsequent electron beam is bent, and it becomes difficult to draw a pattern having high-precision dimensions. Therefore, the resist film is broken, an earth pin is inserted into a conductive film such as a Cr film under the resist film, and the resist film is grounded to suppress the charge of the resist film (see, for example, Patent Document 1).

With the recent miniaturization of patterns, in order to improve the etching resistance of the light-shielding film, it is considered to form a dense insulating film layer on the light-shielding film in order to improve the etching resistance of the light-shielding film. ing. Since a dense insulating film has a high tensile strength, it is difficult for a conventional earth pin to break the dense insulating film only by deforming it even if the load is increased, and it is difficult to penetrate the conductive film under the dense insulating film. There was a problem that it became. As a result, there is a problem that it is not possible to insert the ground pin into the conductive film to ground it, and it becomes difficult to sufficiently suppress the charging of the resist film. On the other hand, if the load is further increased, the quartz glass substrate will be broken this time, leading to a new problem such as generation of particles. This problem is not limited to the mask substrate, and may also occur, for example, when the semiconductor substrate is directly irradiated with an electron beam to draw a pattern. In addition, there may be a problem that the insulating film cannot be broken and the lower conductive layer cannot be reached, not only when the ground is grounded but also when the resistance value of the conductive layer under the insulating film of the semiconductor substrate is measured.

Japanese Unexamined Patent Publication No. 2012-015331

Therefore, one aspect of the present invention provides a conduction contact needle capable of breaking a dense film to be fractured and conducting conduction with the underlying film.

The conduction contact needle of one aspect of the present invention is
It is a conduction contact needle that presses a substrate on which a fractured film is formed on a conductive film from above the fractured film to break the fractured film and conducts with the conductive film.
With the needle body
Multiple convex parts formed on the tip of the needle body,
Equipped with
The plurality of convex portions are characterized in that the tip end portion of the needle body is formed into a rounded curved surface.

Further, it is preferable that the height dimension of the plurality of convex portions is formed to be larger than the film thickness of the film to be broken.

Further, the film to be broken has chromium oxide (CrO ₂ ) and has.
It is preferable that the gap between the adjacent convex portions of the plurality of convex portions is formed to be 1.3 μm or more.

Further, it is preferable that one of a chromium (Cr) film and a tungsten (W) film is used as the conductive film.

Further, it is preferable that one of a semiconductor substrate and an exposure mask substrate is used as the substrate.

According to one aspect of the present invention, it is possible to break a dense fractured film and conduct it with the underlying film. Therefore, it is possible to suppress the charging of other films formed on the conductive film.

It is a block diagram which shows the structure of the conduction contact needle in Embodiment 1. FIG. It is a figure seen from the tip side of the conduction contact needle in Embodiment 1. FIG. It is sectional drawing which shows an example of the conduction state of the conduction contact needle in Embodiment 1. FIG. It is sectional drawing which shows an example of the state before and after the insertion of the tip part of the conduction contact needle in Embodiment 1. FIG. It is a figure which shows an example of the relationship between the size and the number of convex portions and stress in Embodiment 1. FIG. It is a figure which shows an example of the relationship between the size and the number of usable convex portions in Embodiment 1. FIG. It is a figure which shows an example of the relationship between the state of the insulating film pressed by the convex portion in Embodiment 1 and the gap size between adjacent convex portions. It is a figure which shows the relationship between the stress difference applied to the sides of both ends of a convex part in Embodiment 1 and the size of the gap between adjacent convex parts. It is a figure which shows an example of the arrangement state of the convex part in Embodiment 1. FIG. It is a figure for demonstrating the influence on the generated stress of the chamfering process of the edge portion of the tip surface of the convex portion in Embodiment 1. FIG. It is a figure which shows an example of the contact resistance value at the time of pressing from the breaking film by the conduction contact needle in Embodiment 1 and the comparative example. It is a figure which shows another example of the contact resistance value at the time of pressing from the breaking film by the conduction contact needle in Embodiment 1 and the comparative example. It is a figure for demonstrating an example of the contact mark in Embodiment 1 and the comparative example. It is a conceptual diagram which shows the structure of the drawing apparatus in Embodiment 1. FIG. It is a top view which shows the substrate cover in Embodiment 1. FIG. It is a top view which shows the state which the substrate cover of FIG. 15 is attached to a substrate. It is sectional drawing of the substrate cover of FIG. It is a block diagram which shows the structure of the conduction contact needle in Embodiment 2.

Embodiment 1.
FIG. 1 is a configuration diagram showing a configuration of a conduction contact needle according to the first embodiment. FIG. 2 is a view seen from the tip end side of the conduction contact needle in the first embodiment. In FIG. 1, the conduction contact needle 18 according to the first embodiment includes a needle body 13 and a plurality of convex portions 11 formed on the tip of the needle body 13. As shown in FIGS. 1 and 2, the conduction contact needle 18 has a needle body 13 formed of a columnar or square columnar shape, the tip side (lower side in FIG. 1) is tapered, and the tip portion of the tapered portion is further tapered. It is formed on a rounded curved surface, for example, a spherical surface (SR shape). By tapering the tip side, it is possible to easily penetrate into the membrane when pressed. Then, for example, the region 20 of the tip portion formed in a spherical shape is dug from the tip side, and as shown in FIGS. 1 and 2, a plurality of convex portions 11 (or between the convex portions 11) formed in a square columnar shape are formed. Multiple recesses to be formed) are formed. By forming a plurality of convex portions 11 on a curved surface having a rounded tip portion, at least the convex portions 11 formed on the tip of the curved surface can be reliably brought into contact with the conductive film. The region 20 is set to a region larger than the apparent contact surface in the holm equation. As a result, a plurality of protrusions 11 that surely form the true contact surface in the formula of Holm are arranged in the apparent contact surface.

The conductive contact needle 18 is made of a conductive material. For example, it is preferable to use an ultra-high hardness conductive material such as conductive diamond or conductive zirconia. The shape of the needle body 13 may be a triangular column, a pentagonal column, a hexagonal column, or a polygonal column of more than the columnar or square columnar. Further, the tapered tip side may be conical, triangular pyramid, quadrangular pyramid, pentagonal pyramid, hexagonal pyramid, or more polygonal pyramid. Further, the shape of the convex portion 11 may be a rectangular column, a triangular column, a pentagonal column, a hexagonal column, or a polygonal column having more than that. More preferably, a polygonal column or a columnar column having a quadrangular prism or more is desirable.

The size of the needle body 13 is preferably about 0.1 mm to 0.5 mm in cross-sectional diameter or one side of the cross-section. Desirably, 0.2 mm to 0.4 mm is preferable. More preferably, 0.2 mm to 0.3 mm is preferable. The length in the longitudinal direction is preferably about 1 mm to 5 mm. Desirably, 1 mm to 3 mm is suitable. More preferably, 1 mm to 1.5 mm is preferable. The spherical shape of the tip portion is preferably SR 10 μm to 40 μm. Desirably, SR 15 μm to 30 μm is suitable. More preferably, SR 15 μm to 25 μm is preferable. In FIG. 1, the width W of the convex portion 11 and the size of the gap L between the convex portions 11 are shown to be about the same, but as will be described later, the gap L is larger than the width W of the convex portion 11. It is formed large.

FIG. 3 is a cross-sectional view showing an example of a conduction state of the conduction contact needle according to the first embodiment. In the example of FIG. 3, a cross section of an exposure mask substrate for manufacturing a semiconductor device is shown as an example. In the exposure mask substrate 300 (mask blanks before drawing) to which the electron beam is irradiated, the conductive film 304 is formed on the glass substrate 302, the insulating film 306 is formed on the conductive film 304, and the resist is formed on the insulating film 306. The film 308 is formed. As the material of the conductive film 304, for example, chromium (Cr), tungsten (W), chromium nitride (CrNx) and the like can be preferably used. After drawing from the resist film 308, the insulating film 306 remaining after development and etching becomes a light-shielding film, and a mask pattern of the insulating film 306 is formed. As described above, with the recent miniaturization of patterns, in order to improve the etching resistance of the conductive film 304 (light-shielding film) in forming the mask pattern, unlike the conventional case, a dense insulating film is formed on the conductive film 304. Form 306 layers. As the material of the dense insulating film 306, for example, chromium oxide (CrO ₂ ), silicon nitride (SiNx), silicon oxide (SiOx), or the like can be preferably used. The dense insulating film 306 has a high tensile strength. Therefore, with the conventional earth pin, it is difficult to break the dense insulating film 306 even if the resist film can be broken. Regarding this point, even if the load on the ground pin was increased, the dense insulating film 306 could not be broken only by deforming it, and it was difficult to penetrate the conductive film 304 in the lower layer thereof. As a result, there is a problem that the ground pin cannot be inserted into the conductive film 304 and grounded, and it becomes difficult to sufficiently suppress the charging of the resist film 308. On the other hand, in the first embodiment, by forming a plurality of convex portions 11 at the tip portion of the tapered portion of the needle body 13, a dense insulating film 306 and a resist film serving as a broken film are formed on the conductive film 304. The exposure mask substrate 300 (mask blanks before drawing) (an example of the substrate) on which the 308 is formed can be pressed from above the broken film to break the broken film and conduct the conductive film 304. Here, the laminated film of the dense insulating film 306 and the resist film 308 becomes a fractured film for communicating with the conductive film 304. Note that, in FIG. 3, the illustration of the plurality of convex portions 11 at the tip portion of the conduction contact needle 18 is omitted. Next, specifications such as the shape and size of the plurality of convex portions 11 at the tip of the conduction contact needle 18 will be described.

FIG. 4 is a cross-sectional view showing an example of a state before and after insertion of the tip portion of the conduction contact needle according to the first embodiment. FIG. 4A shows a state before inserting the plurality of convex portions 11 of the tip portion of the conduction contact needle 18 into the exposure mask substrate 300 (mask blanks before drawing) similar to FIG. In the exposure mask substrate 300 (mask blanks before drawing), the conductive film 304 is formed, for example, with a film thickness of 10 to 30 nm. The insulating film 306 is formed, for example, with a film thickness of 20 to 40 nm. The resist film 308 is formed, for example, with a film thickness of 80 to 200 nm. When the conduction contact needle 18 is pressed against the exposure mask substrate 300 (mask blanks before drawing) and the plurality of convex portions 11 are inserted from above the resist film 308, as shown in FIG. 4 (b). The plurality of convex portions 11 break the resist film 308 and invade, and then break the underlying insulating film 306. Then, it reaches the conductive film 304 in the lower layer. In that case, the broken resist film 308 and the insulating film 306 are embedded in the gap between the adjacent convex portions 11. Therefore, the height dimension D of the plurality of convex portions 11 is formed to be larger than the total film thickness of the resist film 308 and the insulating film 306 (the film thickness of the film to be broken). For example, if the total film thickness of the resist film 308 and the insulating film 306 is 200 nm (0.2 μm), the height dimension D of the plurality of convex portions 11 is formed to be larger than 0.2 μm. As shown in FIG. 4B, since the film portion pushed by the invasion of the convex portion 11 is also embedded in the gap between the adjacent convex portions 11, the plurality of convex portions 11 have a plurality of convex portions 11. For the height dimension D, it is effective to secure a gap portion through which the pressed film portion can escape. Therefore, it is preferable to form the resist film 308 slightly larger than the total film thickness of the insulating film 306. For example, it is more preferable to make it 1.5 times or more the total film thickness of the resist film 308 and the insulating film 306. For example, if the total film thickness of the resist film 308 and the insulating film 306 is 200 nm (0.2 μm), the height dimension D of the plurality of convex portions 11 needs to be 0.2 μm or more, and is 0.3 μm or more. Then, it is more suitable. For example, when a material having a Poisson's ratio of the resist film 308 of 0.3 to 0.4 is used and the total thickness of the resist film 308 and the insulating film 306 is 200 nm (0.2 μm), a plurality of convex portions are formed. It has been confirmed by experiments that a sufficient conduction effect (resistance value) can be obtained if the height dimension D of 11 is 0.3 μm. It can be obtained by the required height dimension D of the convex portion 11 = (resist film thickness + insulating film thickness) + (resist film thickness × porezone ratio).

FIG. 5 is a diagram showing an example of the relationship between the size, number, and stress of the convex portions in the first embodiment. In FIG. 5, the vertical axis indicates the stress generated in each layer, and the horizontal axis indicates the size of the convex portion. Here, for example, the case where the conduction contact needle 18 is pressed with a load of 0.225N (23gf) is shown. Further, in FIG. 5, 25 (B), 50 (D), and 100 (F) convex portions 11 are formed, and the distribution of each stress acting _{on CrO 2 (insulating film 306) when the convex portions 11 are formed, and} The distribution of each stress acting on the quartz (Qz: glass substrate 302) when 25 (A), 50 (C), and 100 (E) convex portions 11 are formed is shown. The number here indicates the number of the insulating film 306 and the convex portion 11 that presses the quartz.

In the first embodiment, in order for the conductive contact needle 18 to conduct with the conductive film 304, _{it is necessary to break CrO 2} (insulating film 306). Therefore, a size and number of convex portions 11 in which the stress at the tip of the convex portion 11 is larger than the breaking stress of _{CrO 2 (about 3000 MPa in FIG. 5) is required.} On the other hand, if the conduction contact needle 18 breaks the glass substrate 302, particles are generated, which is not desirable. Therefore, it is necessary to have a size and number of convex portions 11 in which the stress at the tip of the convex portion 11 is smaller than the breaking stress of quartz (about 14000 MPa in FIG. 5). Therefore, the usable range of the size and number of the convex portions 11 is determined by the material of the target substrate. When the insulating film 306 is broken by the plurality of convex portions 11, the film is not broken on the entire top surface (tip side end face) of the convex portion 11, but the top surface (tip side end face) of the convex portion 11 is broken. It breaks due to the stress concentration that occurs on the surrounding edges that form. In other words, it can be approximated by shear stress = load / (total length of sides around the top surface of the convex portion 11 × number). Therefore, the stress distribution shown in FIG. 5 is indicated by the value of the concentrated stress generated on the peripheral side of the top surface (end surface on the tip side) of the rectangle. In the conventional ground pin without a plurality of protrusions, the side where the concentrated stress is generated is insufficient or does not exist, so that even if the load for pressing the ground pin is increased, the insulating film 306 is only broken at the tip of the ground pin. No concentrated stress occurs. As a result, the insulating film 306 is only deformed and not broken. On the other hand, in the first embodiment, the plurality of convex portions 11 can generate a concentrated stress sufficient to break the insulating film 306. As a result, the insulating film 306 can be broken to reach the lower conductive film 304.

FIG. 6 is a diagram showing an example of the relationship between the size and the number of usable convex portions in the first embodiment. In FIG. 6, the vertical axis shows the size of the peripheral side (one side of the square) forming the top surface (tip side end surface) of the convex portion 11, and the horizontal axis shows the number of contacts of the convex portion 11 with the film. There is. FIG. 6 shows the range that can be used in the explanation of FIG. 5, and the size and number (number) of the region between the two lines of the breaking stress boundary of _{CrO 2 and the breaking stress boundary of quartz is the range of use of the convex portion.} Become. For example, when the number of contacts of the convex portion 11 to the film is set to 40, the size of the peripheral side (one side of the square) forming the top surface (tip side end surface) of the convex portion 11 is 0.3 μm to 0. It can be formed with a size of .47 μm. For example, when the number of contacts of the convex portion 11 to the film is set to 60, the size of the peripheral side (one side of the square) forming the top surface (tip side end surface) of the convex portion 11 is 0.22 μm to 0. It can be formed with a size of .42 μm. On the contrary, when the size of the peripheral side forming the top surface (tip side end surface) of the convex portion 11 (one side of the square) is set to 0.3 μm, the number of contacts of the convex portion 11 with the film is 40 to 105. It can be formed within the range of. When manufacturing a plurality of convex portions 11, in reality, it is desirable that the size of the peripheral side (one side of the square) forming the top surface (tip side end surface) of the convex portion 11 is 0.05 μm or more. More preferably, a size of 0.2 μm to 0.5 μm is suitable. More preferably, a size of 0.3 μm to 0.4 μm is suitable. It is desirable that the number of contacts of the convex portion 11 with the film is 25 or more. More preferably, 30 to 65 pieces are suitable. When manufacturing the conductive contact needle 18, it is sufficient to form the convex portions 11 having the number of contacts or more determined by the condition range, including the convex portions 11 that do not actually contact the insulating film 306. As a result, the number of convex portions 11 required for breaking the insulating film 306 can be secured.

FIG. 7 is a diagram showing an example of the relationship between the state of the insulating film pressed by the convex portion in the first embodiment and the gap size between the adjacent convex portions. FIG. 7A shows a cross-sectional state of the insulating film 306 pressed by the plurality of adjacent convex portions 11 when the size (distance) L1 of the gap between the adjacent convex portions 11 is formed to be sufficiently large. show. In FIG. 7B, the cross-sectional state of the insulating film 306 pressed by the plurality of adjacent convex portions 11 when the size (distance) L2 of the gap between the adjacent convex portions 11 is formed narrower than sufficient. Is shown. L1> L2. When the convex portion 11 presses the insulating film 306, the insulating film 306 is actually broken due to the action of the surrounding side forming the top surface (tip side end surface) of the convex portion 11. Therefore, it is necessary to generate a concentrated stress on such a side. Here, as shown in FIG. 7B, when the size (distance) L of the gap between the adjacent convex portions 11 is narrow, for example, the left side side a1 of the convex portion 11 located at the left end and the position at the right end. Concentrated stress is generated on the right side b3 of the convex portion 11 to be formed. As a result, the insulating film 306 can be at least deformed (distorted) on the two sides a1 and b3. However, the insulating film 306 deformed by the two sides a1 and b3 maintains a flat state between the two sides a1 and b3. In other words, the insulating film 306 is not deformed at the central convex portion 11. That is, no concentrated stress is generated on the sides a2 and b2 of the central convex portion 11. Similarly, the insulating film 306 is not deformed by the right side b1 of the convex portion 11 located at the left end and the left side a3 of the convex portion 11 located at the right end. In other words, no concentrated stress is generated on the sides b1 and a3. Therefore, even if the load is increased as it is, it becomes difficult to break the insulating film 306 on the sides b1, a2, b2, and a3. As a result, at least the central convex portion 11 cannot come into contact with the lower conductive film 304. In this case, the number of convex portions 11 constituting the true contact surface is insufficient, and the contact resistance value required for antistatic cannot be obtained. On the other hand, as shown in FIG. 7A, when the size (distance) L1 of the gap between the adjacent convex portions 11 is secured to a sufficient size, all of the adjacent convex portions 11 in contact with the insulating film 306 are all. The insulating film 306 can be at least deformed (distorted) at the side of. That is, concentrated stress can be generated on all the sides a1, b1, a3, b3 of the adjacent convex portions 11. Then, if the stress on each side exceeds the shear stress (tensile stress) of the insulating film 306, the insulating film 306 can be broken. As a result, the adjacent convex portions 11 can be brought into contact with the lower conductive film 304. Therefore, the number of convex portions 11 constituting the true contact surface can be secured, and the contact resistance value required for antistatic can be obtained. Therefore, the size (distance) of the gap between the adjacent convex portions 11 so that the stress exceeding the shear stress (tensile stress) of the insulating film 306 can be obtained on all the sides a1, b1, a3, b3 of the adjacent convex portions 11. A plurality of convex portions 11 may be formed at L1.

FIG. 8 is a diagram showing the relationship between the stress difference applied to the sides of both ends of the convex portion in the first embodiment and the size of the gap between the adjacent convex portions. In order for the adjacent convex portions 11 to surely break the insulating film 306 together, the insulating film 306 is deformed (distorted) to the sides at both ends of each convex portion 11 (for example, the sides a1 and b1 in FIG. 7A). ) It is most desirable that the stress is generated and the stress difference generated on the sides at both ends (for example, the sides a1 and b1 in FIG. 7A) becomes zero. In the example of FIG. 8, in order to make the stress difference 0, it can be seen that the size (distance) L of the gap between the adjacent convex portions 11 needs to be 1.8 μm. However, as a result of the experiment, if the size (distance) L of the gap between the adjacent convex portions 11 is 1.3 μm or more, the adjacent convex portions 11 can both break the insulating film 306 even if the stress difference is not 0. I know.

FIG. 9 is a diagram showing an example of the arrangement state of the convex portion in the first embodiment. FIG. 9B shows a case where, for example, a plurality of convex portions 11 are formed in a grid pattern with a size of 1: 1 between the convex portions 11 and the gaps at the tip of the tapered portion of the needle body 13. In such a case, contamination adhered between the convex portions 11 after the conduction work was performed. On the other hand, at the tip of the tapered portion of the needle body 13, for example, a plurality of convex portions 11 in a houndstooth pattern so that the gap L between the convex portions 11 is sufficiently large with respect to the size W of the convex portions 11. Is shown in FIG. 9 (a). In such a case, no contamination was observed after the conduction work was performed. From this result, if the gap dimension L between the adjacent convex portions 11 is too narrow, not only the insulating film 306 is difficult to break, but also the contamination when the resist film 308 is broken is adhered. I understand. Therefore, even when a plurality of convex portions are manufactured by satin finishing or the like in which the gap dimension L between the adjacent convex portions 11 is about the same as the width W of the convex portions, the gap becomes narrow and the same problem occurs. become. From this point as well, it can be seen that it is effective to secure the gap L between the convex portions 11 to a predetermined length or more.

FIG. 10 is a diagram for explaining the influence on the generated stress of the chamfering process of the edge portion of the tip surface of the convex portion in the first embodiment. In the example of FIG. 10, as the stress on the insulating film 306 (CrOx) layer, the size of the peripheral side (one side of the square) forming the top surface (tip side end surface) of the convex portion 11 is set to 0.35 μm. The case of displacement of −0.175 μm is shown as an example. As chamfering of the tip surface of the convex portion 11, the generated stress decreases proportionally as the R dimension is increased from R0.025 μm, an inflection is reached near R0.05 μm, and then the R dimension is increased. As a result, the generated stress converges. Therefore, it is preferable that the edge portion of the tip surface of the convex portion 11 has an acute angle (sharpness), and more preferably smaller than the inflection point (R0.05 μm).

FIG. 11 is a diagram showing an example of the contact resistance value when pressed from above the fractured film by the conduction contact needle in the first embodiment and the comparative example. In FIG. 11A, the surface of the substrate when a conventional earth pin (comparative example) having no plurality of convex portions 11 at the tip is pressed from above the fractured film (laminated film of the insulating film 306 and the resist film 308) of the substrate. An example of the relationship with contact resistance is shown. The unit of the contact resistance value is indicated by the address unit (AU). In FIG. 11B, the conduction contact needle (earth pin) in the first embodiment in which the plurality of protrusions 11 are arranged at the tip is pressed from above the broken film (laminated film of the insulating film 306 and the resist film 308) of the substrate. An example of the relationship between the load and the contact resistance on the surface of the substrate is shown. The unit of the contact resistance value is indicated by the address unit (AU). In the first embodiment and the comparative example, five samples of N1 to N5 were used for measurement. Here, the results of measurement are shown in the range of the load that does not break the quartz (glass substrate 302) so as not to generate particles.
As shown in FIG. 11A, it can be seen that in the conventional ground pin having no plurality of convex portions 11, the contact resistance value hardly changes even if the load is increased. This indicates that the ground pin is not in contact with the conductive film 304 arranged under the insulating film 306. On the other hand, in the first embodiment, as shown in FIG. 11B, it can be seen that the contact resistance value is greatly reduced by applying a load. In the example of FIG. 11B, all the samples are almost converged at 0.2 N or more, and the earth pin of the first embodiment is arranged under the insulating film 306 in any of the samples N1 to N5 at the applied load or more. It can be seen that the conductive film 304 is sufficiently in contact with the conductive film 304. This point indicates that the dense insulating film 306, which is particularly difficult to break among the broken films, can be broken. From the above, it can be seen that the shape of the first embodiment is effective for breaking the insulating film 306 within the range of the load that does not break the quartz (glass substrate 302).

FIG. 12 is a diagram showing another example of the contact resistance value when pressed from above the fractured film by the conduction contact needle in the first embodiment and the comparative example. FIG. 12 shows an example of the measurement result of the contact resistance of the substrate surface obtained by applying the load regardless of whether or not the load breaks the quartz (glass substrate 302). In FIG. 12, the contact resistance of the substrate surface when a conventional ground pin (comparative example) having no plurality of convex portions 11 at the tip is pressed from above the broken film (laminated film of the insulating film 306 and the resist film 308) of the substrate. The surface of the substrate when the conduction contact needle (earth pin) in the first embodiment in which the plurality of protrusions 11 are arranged at the tip is pressed from above the broken film (laminated film of the insulating film 306 and the resist film 308) of the substrate. An example of the measurement result with the contact resistance is shown. Here, a plurality of sample products were prepared for each of the ground pin of the comparative example and the ground pin of the first embodiment, and their effects were measured. In the conventional earth pin (comparative example) which does not have a plurality of convex portions 11 at the tip, the insulating film 306 is broken by some influence due to a large load applied to the sample, and the contact resistance reaches the lower layer thereof. There were some with lower values, but many of them were higher than the allowable threshold value Kth of the contact resistance value even when the load was increased, and the contact resistance values varied. On the other hand, in the first embodiment in which the plurality of convex portions 11 are arranged at the tip, the contact resistance value is suppressed to be lower than the allowable threshold value Kth, and the variation is small. From this point as well, it can be seen that the ground pin of the first embodiment is sufficiently in contact with the conductive film 304 arranged under the insulating film 306 in any of the samples.

FIG. 13 is a diagram for explaining an example of contact marks in the first embodiment and the comparative example. FIG. 13A shows an example of contact marks when the substrate is pressed within a load range that does not break the quartz (glass substrate 302) by using a conventional earth pin (comparative example) having no plurality of convex portions 11 at the tip. Is shown. FIG. 13B shows an example of contact marks when the substrate is pressed within a load range that does not break the quartz (glass substrate 302) by using the first embodiment in which a plurality of convex portions 11 are arranged at the tips. show. In the comparative example, as shown in FIG. 13A, the earth pin does not reach the conductive film 304 only by deforming the film on the surface of the substrate. On the other hand, in the experiment using the first embodiment, as shown in FIG. 13B, the convex portion of the earth pin is deformed to the quartz (glass substrate 302) to generate a mark of the convex portion 11. Is confirmed. As described above, in the first embodiment, the ground pin can reach the conductive film 304.

An example of an apparatus equipped with the conduction contact needle (earth pin) of the first embodiment, which is excellent in breaking the fractured film and conducting with the conductive film 304 as described above, will be described below. In the first embodiment, a configuration using an electron beam will be described as an example of a charged particle beam. However, the charged particle beam is not limited to the electron beam, and a beam using charged particles such as an ion beam may be used. Further, as an example of the charged particle beam apparatus, a variable molding type drawing apparatus will be described.

FIG. 14 is a conceptual diagram showing the configuration of the drawing apparatus according to the first embodiment. In FIG. 1, the drawing apparatus 100 includes a drawing mechanism 150 and a control unit 160. The drawing device 100 is an example of a charged particle beam drawing device. In particular, it is an example of a variable molding type (VSB type) drawing apparatus. The drawing mechanism 150 includes an electronic lens barrel 102 and a drawing chamber 103. An electron gun 201, an illumination lens 202, a first molded aperture 203, a projection lens 204, a deflector 205, a second molded aperture 206, an objective lens 207, and a deflector 208 are arranged in the electron barrel 102. There is. In the drawing chamber 103, an XY stage 105 that can move at least in the XY direction is arranged. A substrate 101 coated with a resist is arranged on the XY stage 105. Here, for example, the above-mentioned exposure mask substrate 300 (mask blanks before drawing) is arranged. In the exposure mask substrate 300 (mask blanks before drawing), each film is on the glass substrate 302 in the order of a light-shielding film (conductive film 304) such as chromium (Cr), an insulating film 306 such as chromium oxide, and a resist film 308. Are laminated. As the substrate 101, a semiconductor substrate for manufacturing a semiconductor device such as a silicon wafer may be arranged instead of the exposure mask substrate 300 (mask blanks before drawing). Also in such a semiconductor substrate, each film is laminated in the order of the conductive film 304, the dense insulating film 306, and the resist film 308. The substrate 101 is arranged on the XY stage 105 with the substrate cover 10 attached. The substrate 101 is connected to the ground of the drawing apparatus 100 via the substrate cover 10 and is maintained at the ground potential.

The control unit 160 has a control computer unit 110, a control circuit 120, and a storage device 140 such as a magnetic disk device. The control computer unit 110, the control circuit 120, and the storage device 140 are connected to each other via a bus (not shown). The control circuit 120 is connected to the drawing mechanism 150 and drives and controls each configuration of the drawing mechanism 150.

Here, FIG. 1 describes the components necessary for explaining the first embodiment. It goes without saying that the drawing apparatus 100 may usually include other necessary configurations. The conduction contact needle 18 presses from above the fractured film of the substrate 101 to break the fractured film and conduct with the conductive film, and the drawing mechanism 150 (irradiation) is in a state where the ground potential is applied to the conduction contact needle 18. The mechanism) irradiates the substrate 101 with an electron beam. Here, the drawing mechanism 150 draws a pattern on the substrate 101 using an electron beam. The operation of the drawing mechanism 150 will be specifically described below.

The electron beam 200 emitted from the electron gun 201 (emission unit) illuminates the entire first molded aperture 203 having a rectangular hole by the illumination lens 202. Here, the electron beam 200 is first formed into a rectangular shape. Then, the electron beam 200 of the first aperture image that has passed through the first molded aperture 203 is projected onto the second molded aperture 206 by the projection lens 204. By the deflector 205, the first aperture image on the second molded aperture 206 is deflected and can change the beam shape and dimensions (variable molding). Such variable molding is performed for each shot, and is usually molded into a different beam shape and size for each shot. Then, the electron beam 200 of the second aperture image that has passed through the second molded aperture 206 is focused by the objective lens 207, deflected by the deflector 208, and placed on the continuously moving XY stage 105. The desired position of 101 is irradiated.

FIG. 15 is a top view showing the substrate cover according to the first embodiment. FIG. 16 is a top view showing a state in which the board cover of FIG. 15 is mounted on the board. FIG. 17 is a cross-sectional view of the substrate cover of FIG. The board cover 10 includes three contact support members 12 (12a, 12b, 12c) and a frame 16 (an example of a frame-shaped member). The contact support members 12 (12a, 12b, 12c) are attached from the upper surface side of the frame 16 at positions that support the substrate cover 10 with three-point instructions. The contact support member 12 (12a, 12b, 12c) is attached so as to project inward from the inner peripheral end of the frame 16. It may be attached not only to project inward but also to project outward from the outer peripheral edge. The contact support member 12 is fixed to the frame 16 by, for example, screwing or welding. On the back surface side of each contact support member 12 (12a, 12b, 12c), a conduction contact needle 18 (here, an earth pin) serving as a contact portion is located inside the inner peripheral end of the frame 16 so that the tip thereof faces the back surface side. Will be placed.

The frame 16 is made of a plate material, and the outer peripheral dimension is larger than the outer peripheral edge of the substrate 101, and the dimension of the opening formed in the inner central portion is smaller than the outer peripheral edge of the substrate 101. That is, as shown in FIG. 16, when the substrate cover 10 is overlapped on the upper portion of the substrate 101 from above, the entire circumference of the outer peripheral portion of the substrate 101 shown by the dotted line is formed so as to overlap the frame 16. In this way, the substrate cover 10 covers the entire outer peripheral portion of the substrate 101 from above. Then, when the substrate cover 10 is attached to the substrate 101, the three conduction contact needles 18 bite into the film formed on the substrate 101 and conduct with the conductive film also formed on the substrate 101.

The substrate cover 10 is preferably entirely made of a conductive material, or is entirely formed of an insulating material and the surface thereof is coated with a conductive material. As the conductive material, a metal material such as copper (Cu) or titanium (Ti) and an alloy thereof is suitable, and as an insulating material, a ceramic material such as alumina is suitable.

Then, by mounting the substrate cover 10 on the substrate 101, the three conductive contact needles 18 break the dense and hard-to-break insulating film and conduct with the lower conductive film. The conduction contact needle 18 is connected to the ground potential via the substrate cover 10. With such a configuration, it is possible to suppress the charge generated by the collision or scattering of the electron beam 200 on the surface of the substrate 101. As a result, it is possible to suppress bending of the orbit of the electron beam 200 and draw a pattern having high accuracy.

As described above, according to the first embodiment, it is possible to break the dense film to be broken and conduct the film with the lower layer film. Therefore, it is possible to suppress the charging of other films formed on the conductive film 304.

Embodiment 2.
In the first embodiment, the case where the tapered tip end of the needle body 13 is formed into, for example, a spherical shape is shown, but the present invention is not limited to this. Hereinafter, the contents other than the points particularly described are the same as those in the first embodiment.

FIG. 18 is a configuration diagram showing the configuration of the conduction contact needle according to the second embodiment. In FIG. 18, the tapered end end side of the needle body 13 of the conduction contact needle 18 may be a flat surface. Then, such a plane may be dug from the tip side to form, for example, a plurality of convex portions 11 (or a plurality of concave portions formed between the convex portions 11) formed of a square columnar shape. Other points are the same as in FIG. Even with such a configuration, it is possible to break a dense fractured film and conduct it with the underlying film. The convex portion 11 formed in FIG. 18 may be formed on the entire surface on the distal end side, or may be formed on a part of the surface. According to the second embodiment, the same effect as that of the first embodiment can be obtained.

The embodiment has been described above with reference to specific examples. However, the present invention is not limited to these specific examples. The substrate into which the conduction contact needle 18 is inserted is not limited to the exposure mask substrate 300, and can be applied to, for example, a case where the semiconductor substrate is directly irradiated with an electron beam and inserted into the semiconductor substrate when drawing a pattern. In addition, it can be applied not only to the case of ground connection but also to the case of measuring the resistance value of the conductive layer under the insulating film of the semiconductor substrate.

Further, although the description of parts not directly required for the description of the present invention such as the device configuration and the control method is omitted, the required device configuration and the control method can be appropriately selected and used. For example, the description of the control unit configuration for controlling the drawing apparatus 100 has been omitted, but it goes without saying that the required control unit configuration is appropriately selected and used.

In addition, all conductive contact needles having the elements of the present invention and which can be appropriately redesigned by those skilled in the art are included in the scope of the present invention.

10 Board cover 11 Convex part 12 Contact support member 13 Needle body 16 Frame 18 Conductive contact needle 100 Drawing device 101 Board 102 Electronic lens barrel 103 Drawing room 105 XY stage 110 Control computer unit 120 Control circuit 140 Storage device 150 Drawing unit 160 Control unit 200 Electron beam 201 Electron gun 202 Illumination lens 203 First molded aperture 204 Projection lens 205 Deflector 206 Second molded aperture 207 Objective lens 208 Deflector 300 Exposure glass substrate 302 Glass substrate 304 Conductive 306 Insulation film 308 Resist film

Claims (6)

A conductive contact needle in which a substrate having a fractured film formed on a conductive film is pressed from above the fractured film to break the fractured film and conduct with the conductive film.
With the needle body
A plurality of convex portions formed on the tip of the needle body,
Equipped with
A conduction contact needle, characterized in that the tip portion of the needle body is formed into a rounded curved surface by the plurality of convex portions. The conduction contact needle according to claim 1, wherein the height dimension of the plurality of convex portions is formed to be larger than the film thickness of the fractured film. The fractured film has chromium oxide (CrO ₂ ) and has.
The conduction contact needle according to claim 1 or 2, wherein a gap between adjacent convex portions of the plurality of convex portions is formed to be 1.3 μm or more. The conductive contact needle according to any one of claims 1 to 3, wherein one of a chromium (Cr) film and a tungsten (W) film is used as the conductive film. The conduction contact needle according to any one of claims 1 to 4, wherein one of a semiconductor substrate and an exposure mask substrate is used as the substrate. The conduction contact needle according to any one of claims 1 to 5, wherein the plurality of convex portions have a side forming a top surface.

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