DE102007063649B4 - Method for producing structures in a resist material and electron beam exposure systems - Google Patents

Abstract

A method for producing a structure in a resist material by means of an electron beam exposure apparatus, the structure having an orientation at an angle other than integer multiples of 45 ° to a reference coordinate of a reference coordinate system of the electron beam exposure apparatus, comprising: imaging a first structure 40) of equal size rectangles (41) of predetermined dimensions in the resist material, wherein the rectangles (41) adjoin one another and are offset from each other in a first direction; and imaging a second structure (40 ') in the resist material that is similar to the first structure (40) but offset from the first structure (40) in the first and second directions, the second direction being perpendicular to the first direction wherein a resulting structure is created by the superposition of the first and second structures (40, 40 ').

Description

In the fabrication of microelectronic or microsystemic devices, structures are formed in layers or substrates by lithographic steps, usually by first forming patterns in suitable resist materials, which are then transferred by appropriate methods into a layer or substrate. As lithographic processes, inter alia, photolithographic exposure processes and electron beam exposure processes are used. In photolithographic processes, structures of a mask are imaged in the resist material, while in electron beam exposure, individual structures are written directly into the resist material by the impact of the electron beam. Since the electron beam exposure is very time-consuming, this technique is mainly used in the production of masks for photolithographic exposure processes and in the production of very small structures in small numbers directly in a resist material on a substrate to be structured.

The in the publication US 5,311,026 A1 The teaching described relates to a system for drawing patterns on a wafer using a charged particle beam, such as an electron beam, in which a complicated pre-alignment mechanism for attaching the wafer to a stage is omitted. Instead, according to the present system, a rotation of the wafer is detected and a shaped beam is rotated by an amount corresponding to the detected value. Subsequently, a predetermined pattern is drawn on the substrate. The system includes a detection device for detecting the rotation of the wafer using an alignment plane or alignment marks; a computer for storing a value corresponding to the thus detected rotation; a rotary lens control circuit for receiving data from the computer; and a rotating lens.

That in the publication US 5,311,026 A1 The electron beam lithography method described comprises expanding the widths of a plurality of strips sharing an area in which electron beam exposure is to be performed such that the boundaries of the strips overlap adjacent strips at each boundary and sequentially expose each of the strips with an electron beam.

In the in the publication JP 2004-333942 A In the above-described writing method using a raster scanning system, the energy beams for scanning are caused by overlapping different stripes (paths) in the X direction for multiple writing to obtain a specified exposure light amount by overlapping the beams. The multiple writing is carried out based on the overlap of stripes in the X direction, which optimizes the exposure state of the resist layer in the overlap-generated area.

US 2007/0 102 651 A1 discloses methods for reducing write time for forming mask patterns with angled and non-angled features using electron beam lithography. In an exemplary embodiment, non-angled features of the mask pattern are formed by exposure to an electron beam. The orientation of the substrate and a path of the generally rectangular shaped shot from the electron beam may be altered relatively so that the substrate is exposed to the electron beam to form the angled features as if they were non-angled features. In another exemplary embodiment, the electron beam lithography system determines whether it is necessary to relatively change the orientation of the substrate and a path of the generally rectangular shaped shot from the electron beam to form the angled features based on the number of angled features and time which is required to relatively change the orientation. Electron beam lithography systems using a rotatable stage, rotatable apertures or both are also disclosed.

From the reference B.Wu, "65 nm node photomask etching with zero CD process bias", Proc. of SPIE, Vol. 5992 (2005), 59920P-1, a robust photomask etching process is known for photomask fabrication at the 65 nm node with zero CD process bias.

Various electron beam systems are used in which both the shape and size of the electron beam impinging on the resist material and the manner of creating contiguous structures may be different. Spot beam and (variable) shaped beam systems on the one hand and raster scan and vector scan systems on the other can be differentiated. A problem that arises in all installations is that the production of structures with an orientation which differs from that of a reference coordinate system of the electron beam installation is only possible to a limited extent. For example, the edge roughness and the angle of the imaged structure are determined by the shape and size of the electron beam. Thus, although spot beam systems with a very small beam diameter structures with a variety of angles and a good edge roughness can be mapped, but the required write time for a variety of structures in the Resist material very high. In the case of variable-shaped beam systems, the electron beam is shaped by means of diaphragms in such a way that structures in the resist material are composed of several large elements that are imaged with the electron beam. This shortens the writing time, but only elements with a restricted shape, such as rectangles and right triangles, can be mapped. As a result, only structures having an orientation which is an integer multiple of 45 ° with respect to the system's reference coordinate system can be imaged with good edge roughness. Structures with other orientations can only be imaged by reducing the imaged elements with a comparable edge roughness, which in turn leads to an increase in the writing time. The orientation of the structure corresponds to the direction in which an edge of the structure extends, wherein the edge has the largest dimension of all edges of the structure.

It is therefore an object of the invention to provide methods and apparatus for producing structures in a resist material in which neither the orientation nor the edge roughness is limited.

This object is achieved by the method according to claims 1 and 8 and solved by a device according to claim 7. Suitable developments can be found in the subclaims.

• 1 eine Ausführungsform eines Substrates mit verschieden orientierten Strukturen;
• 2 ein Flussdiagramm eines Verfahrens darstellt;
• 3 eine Ausführungsform einer Vorrichtung darstellt;
• 4A ein Flussdiagramm eines erfindungsgemäßen Verfahrens darstellt;
• 4B und 4C Draufsichten auf eine abgebildete Struktur nach unterschiedlichen Prozessschritten des Verfahrens aus 4A;
• 5 eine Ausführungsform einer erfindungsgemäßen Vorrichtung darstellt;
• 6A ein Flussdiagramm eines anderen erfindungsgemäßen Verfahrens darstellt;
• 6B und 6C Draufsichten auf eine Struktur nach unterschiedlichen Prozessschritten des Verfahrens aus 6A;
• 7A eine Ausführungsform einer anderen Vorrichtung darstellt;
• 7B die zweite Blende der Vorrichtung aus 7A im Detail darstellt;
• 7C Ausführungsformen von mit der Vorrichtung aus 7A abbildbaren Strukturen;
• 8 ein Flussdiagramm eines anderen Verfahrens darstellt;
• 9A eine Ausführungsform einer anderen Vorrichtung darstellt;
• 9B die zweite Blende der Vorrichtung aus 9A im Detail darstellt;
• 9C Ausführungsformen von mit der Vorrichtung aus 9A abbildbaren Strukturen;
• 10 ein Flussdiagramm eines anderen Verfahrens darstellt;
• 11 ein Flussdiagramm eines anderen Verfahrens darstellt;
• 12 eine Ausführungsform einer anderen Vorrichtung darstellt;
• 13A und 13B Ausführungsformen einer anderen Vorrichtung darstellen;
• 14A ein Flussdiagramm eines anderen Verfahrens darstellt;
• 14B und 14C Ausführungsformen einer Maske, wie sie im in 14A dargestellten Verfahren verwendet wird, darstellen;
• 15 ein Flussdiagramm eines anderen Verfahrens darstellt;
• 16 ein Flussdiagramm eines anderen Verfahrens darstellt;
• 17A eine Ausführungsform eines Substrates nach einem Schritt entsprechend des Verfahrens aus 16 darstellt;
• 17B ein Detail aus 17A darstellt; und
• 17C das Substrat aus 17A nach einem weiteren Schritt entsprechend des Verfahrens aus 16 darstellt.

The methods and devices according to the invention are explained in more detail below with reference to the figures, wherein

• 1 an embodiment of a substrate with differently oriented structures;
• 2 Fig. 10 is a flowchart of a method;
• 3 represents an embodiment of a device;
• 4A a flow chart of a method according to the invention represents;
• 4B and 4C Top views of a pictured structure according to different process steps of the method 4A ;
• 5 represents an embodiment of a device according to the invention;
• 6A Fig. 3 is a flowchart of another method according to the invention;
• 6B and 6C Top views of a structure according to different process steps of the method 6A ;
• 7A represents an embodiment of another device;
• 7B the second aperture of the device 7A in detail represents;
• 7C Embodiments of with the device 7A imageable structures;
• 8th Fig. 10 is a flowchart of another method;
• 9A represents an embodiment of another device;
• 9B the second aperture of the device 9A in detail represents;
• 9C Embodiments of with the device 9A imageable structures;
• 10 Fig. 10 is a flowchart of another method;
• 11 Fig. 10 is a flowchart of another method;
• 12 represents an embodiment of another device;
• 13A and 13B Embodiments of another device represent;
• 14A Fig. 10 is a flowchart of another method;
• 14B and 14C Embodiments of a mask as shown in in 14A illustrated method used represent;
• 15 Fig. 10 is a flowchart of another method;
• 16 Fig. 10 is a flowchart of another method;
• 17A an embodiment of a substrate after a step according to the method 16 represents;
• 17B a detail from 17A represents; and
• 17C the substrate off 17A after a further step according to the method 16 represents.

1 shows an embodiment of a substrate 23 with in a resist material on the surface of the substrate 23 generated structures 231 to 234 , The structures 231 to 234 were produced by means of an electron beam exposure apparatus in the resist material, the electron beam exposure apparatus having a reference coordinate system having the coordinates 101 and 102. The reference coordinates 101 and 102 are perpendicular to each other, and may for example denote an x and a y direction. The substrate 23 For example, it may be a mask for a photolithographic exposure tool (a reticle) or a semiconductor substrate (a wafer) and may include multiple layers and / or multiple materials. For example, the substrate 23 a glass body, a ceramic substrate or other suitable mask layer carrier on which various layers, such as opaque, semi-transparent, phase-shifting or reflective layers, such as Cr or a layer stack of a plurality of molybdenum and silicon layers may be arranged. The substrate 23 may also be any other substrate, such as a support that may include semiconductor materials, insulating or conductive materials. For example, the substrate 23 may comprise a semiconductor substrate, for example of silicon, a silicon-on-insulator (SOI) substrate, a silicon-on-sapphire (SOS) substrate and doped and undoped semiconductor layers or epitaxial layers. SiGe, Ge or GaAs can also be used as semiconductor materials. The substrate 23 may already include structures or devices, such as transistors.

On the surface of the substrate 23 is the resist material arranged in which the structures 231 to 234 are formed. The structures 231 to 234 may be, for example, conductor track structures. The structures 231 and 232 only have edges that run along the coordinates 101 and 102 extend. The structures 233 and 234 have edges that form an angle α or β to the coordinate 101 exhibit. The angles α and β may be different from integral multiples of 45 °, for example. In the resist material can also be a variety of structures 233 and 234 be formed, for example, a line field, as for the structure 234 is shown by way of example. However, other structures, such as triangular structures, may also be formed in the resist material, of which, for example, an edge has an angle other than integer multiples of 45 ° to the reference coordinates.

2 FIG. 3 illustrates a flowchart of a method for producing structures in a resist material by means of an electron beam exposure apparatus. In this case, a first angle of a first structure to be generated with respect to a reference coordinate system of the electron beam exposure apparatus is predetermined (S21). From this angle, a first height of a substrate surface on which the resist material is disposed is determined and set in the electron beam exposure apparatus and with respect to a reference level (S22). The reference height is, for example, the height of the substrate surface in which structures are produced in the resist material whose edges have an angle with respect to the reference coordinate system, which is an integer multiple of 45 °. Thereafter, the first structure is imaged in the resist material, the generated structure having an orientation having the predetermined first angle to the reference coordinate system (S23).

In an electron beam exposure system, such as in 3 is an electron beam from an electron beam source 14 sent. The electron beam is generated by deflection coils 18A . 18B . 21A . 21B distracted and using lenses 17 and 22a . 22b projected onto a substrate 23. On the substrate surface of the substrate 23 An electron-sensitive resist material is arranged in which structures are imaged. In this case, cause elements of the electron beam exposure system, such as the electromagnetic lenses, a rotation of the electron beam. If, for example, by means of diaphragms a non-circular shape of the electron beam impinging on the substrate is produced, then the orientation of the electron beam impinging on the substrate is dependent on the height of the substrate surface with respect to these elements.

For example, if a rectangular electron beam, as in 3 shown by means of a first and a second aperture 15 and 19 produced, so is the orientation of the substrate in the resist material 23 Rectangles produced other than the rectangular electron beam after penetrating the first panel 15 , Typically, the height of the substrate surface is adjusted so that the structures imaged in the resist material have edges extending along the reference coordinates 101 and 102 the electron beam exposure system extend. The reference coordinates 101, 102 may be, for example, an X and a Y direction into which the electron beam passes through the deflection coils 21A . 21B can be distracted. The X and Y directions are usually defined perpendicular to each other. Usually, a substrate holder 24 on which the substrate 23 in the electron beam exposure apparatus, in the same directions, that is, in the X and Y directions, by means of motors 29a . 29b be moved. Thus, rectangular structures whose edges extend along the X or Y direction can be generated.

The height of the substrate surface is now determined and adjusted such that the edges of the rectangular electron beam impinging on the resist material have a predetermined angle to the reference coordinates 101 . 102 exhibit. The angle can be different from integer multiples of 45 °.

Furthermore, it is possible to determine and adjust one or more further heights of the substrate surface in accordance with predetermined angles of further structures to be produced and, while the substrate surface is in contact therewith Heights is to create more structures in the resist material. This makes it possible to generate structures with different angles with respect to the reference coordinates in an exposure system.

A structure to be generated may consist of a plurality of mutually offset, individually imaged elements. For example, a long line structure that extends along the direction 102 extends, composed of a plurality of successively arranged and in the direction 102 adjacent rectangular elements. Since the individual elements of a structure are imaged into the resist material at a predetermined angle, the deflection of the electron beam to image an adjacent element to the angle of the element to be polished is adjusted to the angle of the structure to be formed. For example, now the deflection of the electron beam is not only in the direction 102 but also in the direction 101 so that the individual elements adjoin one another and form a continuous structure with straight edges.

The height of the substrate surface to be set for producing a structure with a predetermined angle can be determined, for example, by means of an allocation table. The assignment table contains data sets, each of which includes an angle and an associated height of the substrate surface. The height determined for a given angle may be set in consideration of the thickness of the substrate by means of a device such as a motor that moves a substrate holder.

Another possibility for determining the height of the substrate surface to be set is to arrange a detector in the electron beam exposure apparatus which determines the rotation of the electron beam at a predetermined height on the basis of a reference structure, for example a rectangle. For this purpose, the electron beam can be deflected so that it impinges on the detector and not on the resist material. Then, the predetermined height is varied until the determined by the detector rotation of the electron beam has the predetermined angle for the structure to be generated. The height thus determined is recorded as the height to be set of the substrate surface and can in turn be adjusted by means of a device as described above. It is possible to arrange the detector at the level of the substrate surface on the substrate holder. Then the determined height can already be set during the determination of the angle corresponding to the angle.

3 represents an embodiment of an electron beam exposure system. The electron beam exposure system 10 includes an electron beam source 14 , which emits an electron beam, devices for focusing, blanking and deflection of the electron beam, aperture 15 . 19 suitable for forming the electron beam, a substrate holder 24 , Devices for moving the substrate holder 24 along coordinates 101 . 102 a reference coordinate system of the plant 10 and a device, the height of the substrate holder from a predetermined angle of a structure to be imaged with respect to the reference coordinate system 24 determines and adjusts.

As in 3 For example, the electron beam focusing, blanking and deflection devices include deflection coils 18A . 18B . 21A . 21B , Projection lenses 17 and 22a . 22b , Condenser lenses 25a . 25b , a blanking electrode 26 , a masking device 27 and a stigmator 30 , The devices for moving the substrate holder 24 on which a substrate 23 are arranged include, for example, interferometers 28a . 28b indicating the position of the substrate holder 24 with respect to the reference coordinate system, and motors 29a . 29b that change the position of the substrate holder. However, other embodiments or spatial arrangements of said devices are possible. The devices for generating, focusing, blanking, deflection and shaping of the electron beam and for moving the substrate holder 24 form an imaging device 100 ,

As in 3 can be seen, some elements and devices of the imaging device 100 shown in simplified form below. For example, the electron beam source 14 , the condensing lenses 25a . 25b and the devices for hiding the electron beam 26 and 27 as the first device area 11 designated. The projection lens 17 and the deflection coils 18A . 18B are hereinafter referred to as the second device area 12 designated. The reduction lenses 22a . 22b , the stigmator 30 and the deflection coils 21A, 21B are hereinafter referred to as the third device region 13.

The electron beam exposure system 10 includes in the 3 illustrated embodiment, a data input device 31 , which may be a computer, for example, as well as a control device 32 , The controller 32 controls the individual devices of the imaging device 100 according to one of the data input device 31 provided datasets 31a , The data set 31a includes besides the dimensions of the imaging device 100 structures to be generated and their angle with respect to the reference coordinate system of the plant 10 ,

The device for determining and adjusting a height of the substrate holder comprises, for example, a motor 29c , which has a certain height of the substrate holder 24 can adjust. The device for determining a height of the substrate holder may, for example, comprise an allocation table, in each of which a predetermined angle of a structure to be generated, a specific height of the substrate holder 24 assigned. Such an allocation table can, for example, in the control device 32 be included.

Another embodiment of the device for determining and adjusting a height of the substrate holder 24 For example, next to the engine 29c a detector, which determines the rotation of the electron beam at a predetermined height based on a reference structure, for example a rectangle. The detector can be arranged on the substrate holder at the level of the substrate surface.

The height of the substrate holder 24 can be changed by a few mm according to the given angles of the structures to be created. The focusing of the electron beam can be readjusted to the respectively set height of the substrate surface.

4A FIG. 1 shows a flowchart of an embodiment of a method according to the invention for producing structures in a resist material by means of an electron beam exposure apparatus. First, a first structure of equal size rectangles having predetermined dimensions in the resist material, which is arranged on a surface of a substrate introduced into the electron beam installation, is produced by means of the Electron beam exposure system generates (S41). Two rectangles each border on each other and are arranged offset in a first direction against each other. Thereafter, a second pattern is formed in the resist material by means of the electron beam exposure apparatus similar to the first structure but offset from the first structure in the first and second directions (S42). The second direction is perpendicular to the first direction.

4B FIG. 12 illustrates a plan view of a structure according to an embodiment of FIG 4A described method after a first process step. As in 4B is seen, becomes a first structure 40 in a resist material 43 pictured a variety of rectangles 41 includes. Here are the rectangles 41 each have the same dimensions, with the edges of the rectangles 41 along reference coordinates 101 respectively. 102 a reference coordinate system of the electron beam exposure system are aligned. Two adjacent rectangles 41 are adjacent to each other and are against each other in one of the directions of the reference coordinate system, in 4B is this the direction 102 arranged offset by an amount a. However, the rectangles can 41 also in the direction 101 be offset from each other. The resulting structure 40 thus has an orientation with respect to the reference coordinate system, by the angle α with respect to the reference coordinate 101 can be described. This angle can be arbitrary by an appropriate selection of the number of rectangles 41 , their dimensions and the size of the offset a are chosen. However, the structure shows 40 a high edge roughness on. The edge 42 , for example, through the lower edges of the rectangles 41 is formed, is not a straight line, but has a staircase shape. It has notches whose maximum distance from an ideal, straight edge line with the angle α is equal to the offset amount a.

4C provides a top view of with reference to 4B described structure after another process step. In the resist material 43 is a second structure 40 ' pictured, the first structure 40 like. The structure 40 is shown by the dashed line. The structure 40 ' includes a number of equal-sized rectangles 41 ' , where the number of rectangles 41 ' , their dimensions and the amount a, around the two rectangles 41 ' offset from each other, equal to the number of rectangles 40 ' , their dimensions and the amount are a. However, the structure is 40 ' by an amount b in the direction 102 and by an amount c in the direction 101 opposite the structure 40 staggered. The amounts b and c are arbitrary. In the in 4C for example, b = a / 2, while c is for example half the dimension of the rectangles 41 or 41 'in the direction 101 is. Deriving from the superposition of structures 40 and 40 ' resulting structure in the resist material 43 has the same orientation as the structure 40 with respect to the reference coordinate system, but lower edge roughness. The maximum distance of the lower edge 42 the resulting structure of an ideal straight edge line with the angle α is equal to the displacement amount b. Thus, the edge roughness of the resulting structure is opposite to the starting structure 40 reduced by the factor a / b.

In one embodiment of the method according to the invention further structures can be produced in the resist material, wherein each further structure of the first structure 40 like. That is, each additional structure includes rectangles whose dimensions and offset are similar to those of the first structure. However, any further structure is to the first and further, previously generated structures in the first and second directions 101 . 102 staggered. For example can follow the in 4C illustrated structure 40 ' a structure 40 '' and a structure 40 ''' be imaged. The structure 40 '' can be, for example, by the amount b / 2 in the direction 102 and by the amount c / 2 in the direction 101 to the first structure 40 be arranged offset. The structure 40 ''' for example, by the amount 3b / 2 in the direction 102 and the amount 3c / 2 in the direction 101 to the first structure 40 be arranged offset. The from the superposition of structures 40 to 40 ''' The resulting structure then has an edge roughness, again by the factor 2 opposite to the structure in 4C is reduced.

By a suitable choice of the dimensions of the rectangles 41 , 41 ', etc., of the amount a, around which the rectangles 41 . 41 ' etc. within a structure 40 . 40 ' . 40 '' etc. are offset against each other, the amounts to the different structures 40 ' . 40 '' etc. with respect to the first structure 40 are arranged offset in the directions of the reference coordinate system, and the number of generated structures 40 ' . 40 '' etc., a structure resulting from the superimposition of the generated structures 40, 40 ', 40 ", etc. may have a predetermined orientation, predetermined dimensions and a predetermined edge roughness in the resist material 43 be generated.

When a vector-scan shaped-beam electron beam exposure apparatus is used to image the structure in the resist material, the starting vector for the second structure becomes 40 ' and optionally further generated structures 40 '' . 40 ''' etc. are each changed by a predetermined amount in the direction of the reference coordinates of the electron beam exposure system.

5 represents an embodiment of an electron beam exposure system according to the invention. The electron beam exposure system 10 includes an imaging device 100 , a data input device 31 and a controller 32. As related to 3 has been explained is the imaging device 100 shown in simplified form. It comprises a first, second and third device area 11 . 12 , 13, two apertures 15 . 19 suitable for forming the electron beam, a substrate holder 24 on which a substrate 23 and devices for determining and changing the position of the substrate holder 24 , for example, interferometers 28a , b and motors 29a , b. The control device 32 controls the individual devices of the imaging device 100 according to one of the data input device 31 provided datasets 31a , The data set 31a includes besides the dimensions of the imaging device 100 structures to be generated also their start vector with respect to the reference coordinate system of the plant 10 , The start vector is variable for each structure to be imaged.

6A FIG. 3 illustrates an embodiment of another method of the invention for producing a structure in a part of a substrate to be structured by means of an electron beam exposure apparatus. The substrate may be any desired substrate, such as a workpiece, a semiconductor wafer or a reticle. It comprises at least one layer in which structures are to be produced using an electron beam exposure system. On a substrate surface, a resist material is arranged. This substrate is introduced into the electron beam exposure equipment (S61).

In the electron beam exposure apparatus, a pattern is imaged into the resist material (S62), the structure comprising a number of equally sized elements, such as rectangles. The elements form a coherent structure. In each case, two elements adjoin one another and are offset relative to one another in a first direction with respect to a reference coordinate system of the electron beam exposure system. The depicted structure has a predetermined orientation with respect to the reference coordinate system and a predetermined roughness of the structure edges.

Subsequently, the resist material is developed to form a resist pattern (S63). The resist pattern is transferred into the layer of the substrate to be structured (S64), for example by means of an etching process. In this case, a substrate structure is generated. The process for transferring the resist pattern includes an over-etching process, so that the roughness of the structural edges is reduced.

6B represents a plan view of a structure 40 according to an embodiment of the with reference to 6A described method after the process step for imaging the structure 40 in a resist material 43 dar. The structure 40 includes a variety of rectangles 41 as related to 4B has been described. The structure 40 has a structural edge 42 that does not represent an ideal straight line but has a staircase shape. The maximum distance of the edge 42 For example, the ideal edge line may be equal to the offset amount a, around which the individual rectangles 41 are offset from each other. This shows the structure shown 40 a predetermined edge roughness.

The mapping of the structure into the resist material may be carried out so that the rectangles have rounded corners. This can be achieved for example by reducing the dose.

Subsequently, the resist material 43 developed, wherein a resist pattern is generated. The resist structure has an edge roughness, that of the edge roughness of the imaged structure 40 similar. However, the edge roughness may be slightly lower. The resist material may be a positive or a negative resist. Thus, the generated resist pattern, for example, an opening in the resist material 43 or a structure of resist material 43 , in whose vicinity the resist material 43 is removed.

After the resist structure has been produced, it is transferred into the layer of the substrate to be structured. This process involves an over-etching process.

The overetching process may comprise, for example, etching of the resist structure prior to the actual transfer to the layer to be structured. In this case, projecting corners of the resist structure can be changed, for example, rounded, that the edge roughness of the resist structure with respect to the imaged structure 40 and the resist pattern formed by developing is reduced. This modified resist structure can then be transferred into the layer to be structured of the substrate, a substrate structure being obtained.

Furthermore, it is possible for the overetching process to comprise the etching of the layer to be structured itself, in which the resist structure is transferred into the layer to be structured. This etching process can be carried out such that the substrate material is not removed as much between projecting regions of the resist structure as at the projecting regions themselves. Thus, a substrate structure having an edge roughness reduced in relation to the resist structure can be obtained.

The process for transferring the resist pattern into the layer of the substrate to be structured may also include both over-etching processes described above, so that the edge roughness can be greatly reduced.

6C provides such a substrate structure 50 She is in the in 6C illustrated embodiment as an opening in a substrate layer 52 carried out, that is, as a resist material, a positive resist was used. The substrate structure 50 has a substrate structure edge 51 on, which is approximately a straight line.

7A represents an embodiment of another electron beam exposure system. The in the 7A illustrated electron beam exposure system comprises an imaging device 100 , a data input device 31 and a control device 32 , As with respect to 3 describes the imaging device 100 a first, second and third device area 11 . 12 . 13 , Irises 15 . 19 suitable for forming the electron beam, a substrate holder 24 on which a substrate 23 is arranged, and devices for determining 28a . 28b and changing 29a , 29b the position of the substrate holder 24 , The first aperture 15 has a rectangular opening aligned with respect to a reference coordinate system of the electron beam exposure apparatus. That is, the aperture is oriented so that an electron beam formed therewith images a rectangular structure into a resist material on a surface of the substrate whose edges run along reference coordinates 101, 102 of the reference coordinate system.

The second aperture 19 has an opening 190 on that in 7B is shown in detail. The opening 190 includes a rectangular opening 190a and an opening 190b in the form of a parallelogram, one corner with the rectangular opening 190a can be superimposed, as in 7B you can see. The parallelogram has angles that are different from 90 °. The rectangular opening 190a is aligned with respect to the reference coordinate system such that the edges of one through the first aperture 15 shaped and incident on the second diaphragm 19 electron beam 16 towards the edges of the opening 190a run. The opening 190b is about the opening 190a arranged so rotated that at least two edges of the opening 190b not in the direction of the edges of the opening 190a run. An angle γ is between a first edge of the opening 190b and a parallel to a first edge of the opening 190a Are defined. An angle δ is between a second edge of the opening 190b and the parallels to the first edge of the opening 190a defined, with the parallel to the first edge of the opening 190a does not pass through an angle ε between the first and second edges of the opening 190b is present. The angles γ and δ may be the same or different from each other. That is, the opening 190b may be arranged symmetrically or asymmetrically with respect to the opening 190a. For example, if the angle ε of the parallelogram is 120 °, the angles γ and δ may be, for example, 30 ° and 30 ° or 45 ° and 15 ° or 60 ° and 0 °. The following applies: ε + γ + δ = 180 °.

In 7B are different overlay variants of the electron beam 16 and the opening 190 the second aperture 19 exemplified. The one formed by the overlay electron beam 20 can, for example, the forms 20a to 20e. The electron beam 20a has, for example, a rectangular shape, while the electron beams shown 20b to 20e For example, have the shape of rectangular triangles, the catheters are each different lengths. The dimensions of the edges of the shaped electron beam 20 are dependent on the dimensions of the edges of the incident electron beam 16 and the superposition of the electron beam 16 with the opening 190 freely selectable. The angles of the electron beam 20 with triangular shape are defined by the angles and the arrangement of the edges of the parallelogram 190b determined with respect to the reference coordinate system.

7C exemplifies various structures using the electron beams 20a to 20e in a resist material that is on the surface of the substrate 23 in 7A is arranged, can be mapped. The structures A and B comprise elements caused by the superposition of the electron beam 16 with the opening 190a , for example with the electron beam 20a to be imaged. They have orientations of 0 ° and 90 ° to the reference coordinates 101 , 102 of the electron beam exposure system. The structure C includes elements caused by the superposition of the electron beam 16 with the opening 190b on opposite sides of the opening 190b , for example with the electron beams 20b and 20d. The structure C has an orientation with the angle 180 ° -γ with respect to the reference coordinate, along the direction of the first edge of the opening 190a runs. In the in the 7B and 7C In the embodiment shown this is, for example, the coordinate 101 , The structure D comprises elements caused by the superposition of the electron beam 16 with the opening 190b on other opposite sides of the opening 190b , for example with the electron beams 20c and 20e to be imaged. The structure D has an orientation with the angle δ with respect to the reference coordinate, along the direction of the first edge of the opening 190a runs. In the in the 7B and 7C In the embodiment shown this is, for example, the coordinate 101 ,

In the 7A illustrated electron beam exposure system 10 may in one embodiment a plurality of second aperture 19 include, wherein the various second aperture 19 through the angles of the opening 190b and the arrangement of the opening 190b concerning the opening 190a differ.

In one embodiment, the various second apertures are 19 as revolver apertures in the plant 10 arranged.

In another embodiment, the various second apertures are 19 as separate panels on a common panel in the system 10 arranged. In this case, for example, in each separate aperture both openings 190a and 190b be educated. However, the opening can also be 190a be formed only once, while various openings 190 b are arranged on the diaphragm support, and the various apertures 19 a combination of an opening 190a and a selected opening 190b includes.

8th FIG. 12 illustrates an embodiment of a method in which a structure in a resist material is described by reference to FIG 7A to 7C described electron beam exposure system is generated. A substrate on the surface of which the resist is applied is introduced into the electron beam exposure equipment (S81). A structure is created in the resist material (S82), the structure having an orientation different from the coordinates of the reference coordinate system of the electron beam exposure apparatus. The structure is generated by an electron beam, which is formed by the superposition of the first and the second aperture of the electron beam exposure apparatus. For example, one of the structures C or D that is in 7C are shown generated.

In one embodiment of the method, the electron beam exposure system comprises a plurality of different second diaphragms as described above. Then, the method for producing a structure comprises the step of selecting the second diaphragm in which the angles and the arrangement of the parallelogram-shaped opening are adapted to the orientation of the structure to be generated.

Structures having mutually different orientations, each different from the reference coordinates, may be generated by, for example, performing the described method a plurality of times using different second apertures.

9A represents an embodiment of another electron beam exposure system. The in the 9A illustrated electron beam exposure system comprises an imaging device 100 , a data input device 31 and a control device 32 , As with respect to 3 describes the imaging device 100 a first, second and third device area 11 . 12 . 13 Apertures 15, 19 suitable for forming the electron beam include a substrate holder 24 on which a substrate 23 is arranged, and devices for determining 28a . 28b and changing 29a, 29b the position of the substrate holder 24 , The first cover 15 has a rectangular opening aligned with respect to a reference coordinate system of the electron beam exposure apparatus. That is, the aperture is oriented so that an electron beam formed therewith images a rectangular structure into a resist material on a surface of the substrate, whose edges are along reference coordinates 101 . 102 of the reference coordinate system.

The second aperture 19 has an opening 190 on that in 9B is shown in detail. The opening 190 includes a rectangular opening 190a and an opening 190b in the form of a parallelogram, one corner with the rectangular opening 190a can be superimposed, as in 9B you can see. The opening 190b is about the opening 190a arranged so rotated that at least two edges of the opening 190b not in the direction of the edges of the opening 190a run. An angle γ is between a first edge of the opening 190b and a parallel to a first edge of the opening 190a Are defined. An angle δ is between a second edge of the opening 190b and the parallels to the first edge of the opening 190a, the parallel to the first edge of the opening 190a does not pass through an angle ε between the first and second edges of the opening 190b is present. The angles γ and δ may be the same or different from each other. That is, the opening 190b can be symmetrical or unbalanced to the opening 190a be arranged. For example, the opening 190b as in 7B shown executed and with respect to the opening 190a be arranged.

It is also possible that the opening 190b is a rectangle and the angles γ and δ are each 45 °, as in 9B is shown. Furthermore, a corner of the opening 190b may be covered so that the resulting edge is parallel to an opposite edge of the opening 190a runs like this in 9B you can see.

At least one of the openings in the panels 15 and 19 is rotated with respect to the reference coordinate system of the electron beam exposure apparatus. That is, the openings in the panels 15 and 19 are aligned so that the edges of one through the first aperture 15 shaped and on the second panel 19 incident electron beam 16 in directions that run from the directions of the edges of the opening 190a are different. Between a parallel to a first edge of the electron beam 16 and a first edge of the opening 190a an angle φ is defined. In 9B is for example the opening in the aperture 15 arranged so that only through the aperture 15 formed electron beam, a structure in a resist material, which on the surface of the substrate 23 is arranged, whose edges run along the directions of the reference coordinates. In contrast, the opening 190 in the aperture 19 rotated, leaving a sole figure, for example, the opening 190a in the resist material would create a structure whose edges do not run along the directions of the reference coordinates. The angle φ is freely selectable and may for example be greater than 10 °, for example greater than or equal to 18 °. The angle φ may, for example, be less than 45 °, for example less than or equal to 22 °.

In 9B are different overlay variants of the electron beam 16 and the opening 190 the second aperture 19 exemplified. The electron beam formed by the superposition 20 can, for example, the forms 20a until 20h. The illustrated resulting electron beams 20a to 20h have, for example, the shape of rectangular triangles whose catheters each have different lengths. The dimensions of the edges of the shaped electron beam 20 are dependent on the dimensions of the edges of the incident electron beam 16 and the superposition of the electron beam 16 with the opening 190 freely selectable. The angles of the electron beam 20 with triangular shape are defined by the angles and the arrangement of the edges of the parallelogram 190b with respect to the edges of the incident electron beam 16 certainly.

9C exemplifies various structures using the electron beams 20a to 20e can be imaged in the resist material. The structures A and B have orientations of 0 ° and 90 ° to the reference coordinates 101, 102 of the electron beam exposure system. The structure A can, for example, elements that with the electron beam 20b be imaged, and elements with the electron beam 20h be imaged include. The structure A, however, may also include, for example, elements associated with the electron beam 20c be imaged, and elements with the electron beam 20f be imaged include. By a different arrangement of the same elements, of a structure A However, the structure F or the structure E can also be generated. The structure E has an orientation at an angle of 180 ° -φ to the reference coordinate 101 while the structure F is an orientation with the angle φ to the coordinate 101 having. For example, the structure B may be elements associated with the electron beam 20d be imaged, and elements with the electron beam 20g be imaged include. However, structure B may also include, for example, elements associated with the electron beam 20e be imaged, and elements with the electron beam 20a be imaged include. By a different arrangement of the same elements, which are covered by a structure B, but also the structure D or the structure C can be generated. The structure C has an orientation at an angle of 180 ° -φ to the reference coordinate 102 while the structure D is an orientation with the angle φ to the coordinate 102 having.

In the 9A In an embodiment, the electron beam exposure apparatus 10 illustrated may comprise a plurality of aperture sets, wherein a pair of apertures each comprise a first aperture 15 and a second aperture 19 and wherein the different diaphragm sets differ by the angles of rotation of the openings in the first or the second diaphragm or in both diaphragms with respect to the reference coordinate system.

In one embodiment, the various sets of apertures are in the plant as turrets 10 arranged. In this case, for example, different first or second aperture 15 . 19 be designed as turret covers. That is, at least one of the panels 15 or 19 is arranged in several embodiments with different angles of rotation of the respective aperture as turret aperture.

In another embodiment, the different aperture sets are made by the combination of different first and second apertures 15 . 19 realized, with different apertures 15 or 19 each as separate apertures on a respective common aperture support for the first and the second aperture 15 . 19 in the plant 10 are arranged. The electron beam is then deflected in each case so that a predetermined combination of a first aperture 15 and a second aperture 19 is realized.

In a further embodiment, at least one of the apertures 15 . 19 through a device in the plant 10 be rotated according to a predetermined angle. Such a device may, for example, be a motor which corresponds to a data set received from the data input device 31 to the control device 32 is controlled.

When using such an electron beam exposure system 10 Data of the data set, for example the decomposition of the structure to be produced in the resist material into individual elements to be imaged, are adapted to the elements which can be imaged with the rotated diaphragms.

10 FIG. 12 illustrates an embodiment of a method in which a structure in a resist material is described by reference to FIG 9A to 9C described electron beam exposure system is generated. A substrate on the surface of which the resist material is applied is introduced into the electron beam exposure equipment (S101). A structure is created in the resist material (S102), the structure having an orientation different from the coordinates of the reference coordinate system of the electron beam exposure apparatus. The structure is generated by an electron beam, which is formed by the superposition of the first and the second aperture of the electron beam exposure apparatus. For example, one of the structures C to F shown in FIG 9C are shown generated.

In one embodiment of the method, the electron beam exposure system comprises a plurality of different aperture sets as described above. Then, the method for producing a structure comprises the step of selecting that aperture set in which the rotational angles of the openings in the first and second apertures are adapted to the orientation of the structure to be generated.

In an embodiment of the invention with reference to 10 described method, the rotation of at least one opening of the first or the second diaphragm with respect to the reference coordinate system by the rotation of the first and the second diaphragm is generated according to a predetermined angle by means of a device for rotation.

Structures with mutually different orientations that are different from the reference coordinates can be generated, for example, by repeatedly executing the method described using different aperture sets or by setting different angles of rotation of the first and / or the second diaphragm.

11 FIG. 3 illustrates an embodiment of another method for producing structures in a resist material by means of an electron beam exposure apparatus. The electron beam exposure apparatus may be, for example, a vector-scan installation. A substrate on the surface of which the resist material is applied is introduced into the electron beam exposure equipment (S111). A first rotation angle of the substrate with respect to a reference coordinate system of the electron beam exposure apparatus is set (S112). A first structure is generated in the resist material at the first rotation angle, the first structure having a first orientation with respect to the reference coordinate system that is different from the orientation of the reference coordinates (S113).

In an embodiment of the with respect to 11 described method, the first rotation angle by rotation of a substrate holder, above or on the Substrate is arranged in the electron beam exposure system, set. However, the substrate holder itself is still moved along the directions of the reference coordinates within the electron beam exposure apparatus.

In another embodiment, the first rotation angle is set by means of an arrangement of the substrate corresponding to the first rotation angle on a substrate holder on which the substrate is arranged in the electron beam exposure apparatus. This can be realized, for example, by rotating the substrate on a charging device which removes the substrate from a charging station, which is arranged, for example, on the outside of the electron beam exposure system, and arranges it on the substrate holder. Another possibility is the use of special substrate loaders on which the substrate is arranged at a predetermined angle of rotation. Such a substrate loader (template) can be removed with the substrate arranged thereon a charging station and arranged on the substrate holder of the electron beam exposure system.

Further rotation angles of the substrate can be adjusted, for example by means of one of the embodiments described above. In the case of the further rotation angles, further structures can be produced in the resist material, which each have further orientations which are different from the first orientation and from the orientation of the reference coordinates.

12 represents an embodiment of an electron beam exposure system. The electron beam exposure system can be a vector-scan system, for example a vector-scan system with a variably shaped electron beam. In the 12 illustrated embodiment includes, for example, an imaging device 100 , a data input device 31 and a control device 32 , The imaging device includes first, second and third device regions, apertures 15 and 19 , a substrate holder 24 on which a substrate 23 is arranged, as well as devices for determining the position 28a . 28b and moving 29a . 29b of the substrate holder 24 , The device comprises a device 29d for setting a predetermined rotation angle α of the substrate holder 24 with respect to reference coordinates 101 , 102 of the electron beam exposure system 10 ,

13A represents a further embodiment of an electron beam exposure system. In 13A are an imaging device 100 with a substrate holder 24 , a charging station 60 and a loader 61 shown. In the charging station 60 can be at least one substrate 23 be provided on the surface of a resist material is applied, in which a structure is to be produced by means of the electron beam exposure system. The loading device 61 includes, for example, a loading arm 611 , at the end of a Substrataufnehmer 612 is appropriate. The loading arm 611 For example, it can be moved along the direction of a reference coordinate 101 of the electron beam exposure apparatus and is rotatably mounted. Thus, the loading arm 611 be moved so that the Substrataufnehmer 612 the substrate from the charging station 60 remove and on the substrate holder 24 can arrange. The substrate receiver 612 can be rotatable with respect to the loading arm 611 be stored so that the substrate 23 with a predetermined rotation with respect to a reference coordinate system of the electron beam exposure apparatus, for example with reference coordinates 101 . 102 can be placed on the substrate holder, as in 13 shown by the dashed outline. The substrate receiver 612 may be any predetermined rotation of the substrate 23 realize.

13B represents another embodiment of an electron beam exposure system. In 13B are an imaging device 100 with a substrate holder 24 and a loader 61 shown. It can be a substrate 23 be provided on the surface of a resist material is applied, in which a structure is to be produced by means of the electron beam exposure system. The loading device 61 includes a substrate loader 613 (template), which has a recess 614 with the shape and dimensions of the substrate 23 having. The depression 614 has a rotation with an angle α with respect to a reference coordinate 101 of the reference coordinate system of the electron beam exposure apparatus 10. The substrate 23 can in the recess 614 of the substrate loader 613 arranged and with the substrate loader 613 on the substrate holder 24 be arranged, wherein the substrate 23 has a fixed, predetermined angle α to the reference coordinate 101. This is in 13B represented by the dashed outlines. The substrate loader 613 has similar properties (thermal expansion, electrical properties) as the substrate.

The substrate loading device 61 can use different substrate loaders 613 include, each substrate loader 613 a recess 614 having a fixed, predetermined angle α, which is suitable for each substrate loader 613 is different. Thus, in each case the substrate loader 613 whose depression 614 have a desired angle α, are used to the substrate 23 above the substrate holder 24 to arrange and a fixed, predetermined rotation of the substrate 23 to realize in the electron beam exposure system.

14A FIG. 10 illustrates a flowchart of one embodiment of another method for creating a pattern in a resist material. First, a photolithographic mask having at least one pattern is formed by means of a mask writer, which may be, for example, an electron beam exposure tool (S141). A substrate on the surface of which the resist material is deposited is placed in a photolithographic exposure apparatus (S142). This exposure apparatus includes the photolithographic mask formed in step S141. Then, in the resist material, by means of the photolithographic exposure apparatus, using the generated mask, a structure having a different orientation from a reference coordinate system of the mask writing apparatus is produced (S143). The angle between this orientation and the coordinates of the reference coordinate system may, for example, be different from integer multiples of 45 °.

In one embodiment of the method, at least one alignment mark is produced during the production of the photolithographic mask, by means of which the substrate and the mask are adjusted to one another when the substrate is introduced into the photolithographic exposure system.

In one embodiment of the method, the structure is produced in the photolithographic mask by one of the methods described above. That is, step S141 includes one of the above-described methods, and the mask includes at least one structure having a different orientation from the reference coordinate system of the mask writer. The angle between this orientation and the coordinates of the reference coordinate system may, for example, be different from integer multiples of 45 °.

Furthermore, an alignment mark can be generated in the photolithographic mask, which has, for example, orientations which correspond to the reference coordinate system of the mask writing system. The angles between the orientations of partial structures of the alignment mark and the coordinates of the reference coordinate system can be, for example, integer multiples of 45 °.

14B FIG. 12 illustrates one embodiment of a mask made in accordance with the method described above. The mask 70 can be a mask structure 71 and an alignment mark 72 include. The edges of the mask structure 71 have an angle α with respect to the reference coordinate 73 the mask writing system, which is different from integer multiples of 45 °. By contrast, the alignment mark points 72 Orientations on the reference coordinates 73 . 74 correspond to the mask writing system. In this case, the edge roughness of the alignment mark 72 greater than the edge roughness of the mask structure 71 be. The alignment mark can also be generated with a low edge roughness with increased writing time. The mask structure 71 can be imaged by means of a photolithographic exposure system in a resist material on a substrate, wherein the alignment mark 72 to adjust the mask 70 and the substrate is used.

In another embodiment of the method, the structure in the photolithographic mask is produced by a known method. The mask then only comprises structures which have orientations with respect to the reference coordinate system of the mask writing system, in which the angle between these orientations and the reference coordinates is an integer multiple of 45 °. The mask and / or the substrate are now introduced into the photolithographic exposure system in such a way that the structures in the mask have orientations with respect to a reference coordinate of the substrate, which are different from integer multiples of 45 °. This can be realized by rotation of the mask or rotation of the substrate or rotation of the mask and the substrate at mutually different angles in the photolithographic exposure system. Upon rotation of both the mask and the substrate, the one rotation angle is different from the sum of the other rotation angle and an integer multiple of 45 °.

In one embodiment, an alignment mark is further generated in the mask having orientations that are different from the reference coordinate system of the mask writing system. The angles between the orientations of partial structures of the alignment mark and the coordinates of the reference coordinate system may be different, for example, from integer multiples of 45 °.

14C FIG. 12 illustrates one embodiment of a mask made in accordance with the method described above. The mask 75 can be a mask structure 76 and an alignment mark 77 include. The edges of the mask structure 76 have angles with respect to the reference coordinates 73 . 74 of the mask writer, which are integer multiples of 45 °. By contrast, the alignment mark points 77 one of which is different orientation, with the angles between the edges of the alignment mark 77 and the reference coordinates 73 . 74 the mask writing system of integer multiples of 45 ° are different. In this case, the edge roughness of the alignment mark 77 be greater than the edge roughness of the mask structure 76. The alignment mark can also be generated with a low edge roughness with increased writing time. The mask structure 76 can be imaged by means of a photolithographic exposure system in a resist material on a substrate. In this case, the substrate and the mask are rotated relative to each other, wherein the alignment mark 77 to adjust the mask 70 and the substrate is used. As a result, the structure produced in the resist material has an orientation which is different from the reference coordinate system of the mask writing system.

In a further embodiment of the with reference to 14A described method is produced by means of an electron beam exposure system at least one further structure in the resist material, which has a different orientation from the first structure. In this case, the angle between the orientation of the first structure and the orientation of the further structure can not be an integer multiple of 45 °. The further structure can be produced before or after the first structure is produced in the resist material. If the further structure is produced after the first structure has been produced, then it can be adjusted with the aid of the at least one alignment mark with respect to the first structure. For example, the alignment mark may have orientations that correspond to a reference coordinate system of the electron beam exposure system. If the further structure is generated before the first structure is produced, then at least one alignment mark in the resist material corresponding to the reference coordinate system of the mask writing system can be produced by means of the electron beam exposure apparatus. With the aid of this alignment mark, the at least one structure of the mask within the photolithographic exposure system can be adjusted with respect to the further structure.

The mask writer and the electron beam exposure tool may be the same or different equipment.

The substrate on which the resist material is applied may be, for example, a reticle, and the structure formed in the resist material may be a mask pattern.

15 FIG. 12 illustrates a flowchart of one embodiment of another method. First, one of the methods described above is executed (S151), wherein at least one first structure is generated. Thereafter, another of the above-described methods is executed (S152), whereby at least one second structure is generated. This includes the in 15 The method illustrated a combination of the methods described above, wherein any combinations with a different number of combined methods are possible.

16 FIG. 10 illustrates a flowchart of one embodiment of a method of forming patterns in a resist material disposed on a substrate. First, at least one first pattern is formed in the resist material by means of an electron beam exposure apparatus, the first structure having an orientation relative to a reference coordinate system of the electron beam exposure tool (S161). The angle between this orientation and the coordinates of the reference coordinate system may be an integer multiple of 45 °. In the same electron beam exposure apparatus, at least one alignment mark is formed in the resist material which is rotated with respect to the coordinates of the first reference coordinate system at a predetermined angle (S162). The alignment mark can be composed of several elements, wherein the angle between the edges of the elements and the coordinates of the reference coordinate system can be integer multiples of 45 °. Thereafter, at least a second pattern is formed in the resist material by means of another exposure equipment (S163). The second structure may be formed by means of an electron beam exposure apparatus using one with reference to FIGS 2 or 11 described method are generated. However, the second structure may also be constructed using another method, such as one with reference to FIGS 8th or 10 described method, or be generated by means of another exposure system. The second structure has an orientation with respect to the first structure, wherein the angle between this orientation and the orientation of the first structure is different from integer multiples of 45 °. When creating the second structure, the substrate is adjusted relative to the first structure by means of the at least one alignment mark.

Based on 17A to 17C will that be in 16 illustrated method explained in more detail. 17A shows a substrate 23 , the first two structures 231 and 232 comprising, by means of an electron beam exposure apparatus in a resist material 80 on the surface of the substrate 23 were generated. The first structures 231 and 232 have orientations with respect to the coordinates 101 . 102 of the reference coordinate system of the electron beam exposure apparatus. As in 17A can represent the angles between these orientations and the coordinates 101 or 102 integer multiples of 45 °. The structures 231 and 232 have a desired low edge roughness. Furthermore, the substrate comprises 23 at least one alignment mark 235 also by means of the electron beam exposure system in the resist material 80 was generated. The alignment mark 235 is arranged rotated relative to the reference coordinate system.

17B shows an embodiment of the alignment mark 235 in detail. The alignment mark 235 can be composed of a plurality of elements, for example, equal-sized rectangles, which are offset from each other, similar to that with reference to 4B is described. The angles between the edges of the elements and the reference coordinates 101 . 102 can be integer multiples of 45 °. This indicates, for example, the resulting substructure 235a the alignment mark 235 an orientation with respect to the reference coordinate system, by the angle α with respect to the reference coordinate 101 can be described. Other substructures of the alignment mark 235 , for example, the in 17B illustrated substructure 235b , Any orientation to the substructure 235a exhibit. For example, the substructure 235b perpendicular to the substructure 235a be arranged. The alignment mark 235 can have a high edge roughness compared to the structures 231 and 232 exhibit.

The alignment mark 235 However, it can also be generated differently. For example, the alignment mark 235 composed of other elements or produced by other methods. The alignment mark can be generated for example with a low edge roughness at increased writing time.

Below is at least a second structure 233 by means of a further exposure system in the resist material 80 generated. The second structure 233 For example, by means of an electron beam exposure apparatus using a with respect to the 2 or 11 described method are generated. In the process, the substrate becomes 23 concerning the first structures 231 . 232 with the help of the alignment mark 235 adjusted. The structure 233 has an orientation with respect to the first structures 231 . 232 on, with the angle between the orientation of the structure 233 and the orientation of the structure 231 or 232 is different from integer multiples of 45 °. For example, the structure 233 an angle β to the first structure 232 exhibit. The angle β, for example, equal to the angle α of the alignment mark 235 be. The resulting substrate 23 is in 17C shown.

The further exposure system may be the same as the electron beam exposure device or another. The first structures 231 . 232 and the alignment mark 235 For example, they can only be latent in the resist material 80 that is, the structures have been imaged but not yet developed.

However, the structures can 231 . 232 and the alignment mark 235 also in the resist material 80 are developed, wherein first resist structures and an alignment mark are produced in the resist material, which in a layer to be structured below the resist material 80 are transmitted, wherein first substrate structures and an alignment mark are generated in the layer to be structured. The second structure 233 is then imaged into a new resist material that is the resist material 80 can replace. By means of the further exposure system becomes the second structure 233 imaged in the new resist material, wherein the substrate with respect to the first structures 231 . 232 is adjusted by means of the alignment mark in the layer to be structured. The new resist material can subsequently be developed and the second structure produced in the resist material can be transferred into the layer to be structured.

The methods described above make it possible to generate a structure by means of an electron beam exposure apparatus, the structure having an orientation which is different from the reference coordinate system of the electron beam exposure apparatus. In particular, the angle between this orientation and the reference coordinates may be different from integer multiples of 45 °. In this case, the structure produced has a roughness of the structural edges which is equal to or at least very close to that of structures which were produced by means of known methods in an electron beam exposure apparatus. Thus, the same requirements regarding the uniformity of feature sizes, the structural edge roughness, and the structural errors for both structures having an orientation in which the angle between this orientation and the reference coordinates is an integer multiple of 45 °, as well as for structures having a Having orientation in which the angle between this orientation and the reference coordinates of integer multiples of 45 ° is different, are met. In particular, when using shaped-beam electron beam exposure systems, a write speed which is higher than spot-beam systems and which is the same for both types of structures can be achieved.

Claims (11)

A method for producing a structure in a resist material by means of an electron beam exposure apparatus, the structure having an orientation at an angle other than integer multiples of 45 ° to a reference coordinate of a reference coordinate system of the electron beam exposure apparatus, comprising: imaging a first structure 40) of equal size rectangles (41) of predetermined dimensions in the resist material, wherein the rectangles (41) adjoin one another and are offset from each other in a first direction; and - Imaging a second structure (40 ') in the resist material that is similar to the first structure (40) but offset from the first structure (40) in the first and second directions, the second direction being perpendicular to the first direction; wherein a resulting structure is created by the superposition of the first and second structures (40, 40 '). Method according to Claim 1 characterized in that further structures are imaged into the resist material, wherein each further structure comprises rectangles whose dimensions are similar to those of the first structure (40) but offset from the first and other previously created structures in the first and second directions is. Method according to Claim 1 characterized in that the dimensions of the rectangles (41), the amount by which the adjacent rectangles (41) are offset from each other, and the amounts by which the second structure is offset from the first structure in the first and second directions, are such it can be chosen that the superimposition of the first and the second structure (40, 40 ') results in a structure with a predetermined orientation, predetermined dimensions and predetermined structural edge roughness. Method according to Claim 2 characterized in that the dimensions of the rectangles (41), the amount by which contiguous rectangles (41) are offset from one another, the number of further structures produced and the amounts by which the second and the generated further structures are related first structure (40) are offset in the first and the second direction, are selected so that from the superposition of the first, the second and the further structures (40, 40 ', ...) a structure with a predetermined orientation, given dimensions and given structural edge roughness. Method according to Claim 1 , characterized in that a Vector-scan shaped-beam system is used as the electron beam exposure apparatus, and the start vector for the step of generating the second structure (40 ') is changed by a predetermined amount in the first and second directions. Method according to Claim 2 , characterized in that a Vector-scan shaped-beam system is used as electron beam exposure apparatus, and the start vector for the steps for generating the second and the further structures is changed in each case by a predetermined amount in the first and the second direction. Vector-scan shaped-beam electron beam exposure system, with - devices (11, 12, 13) for focusing, fading out and deflecting an electron beam, - Devices for moving a substrate holder (28 a, 28 b, 29 a, 29 b), and - A control device (32) which is suitable, the devices (11, 12, 13) for focusing, Ausblendung and deflection of an electron beam and the means for moving a substrate holder (28 a, 28 b, 29 a, 29 b) according to a provided data set (31 a ), wherein the data set (31a) for similar images (40, 40 ') to be imaged with the electron beam exposure apparatus, have the same dimensions and a same orientation with respect to a reference coordinate system of the electron beam exposure apparatus but are offset from each other, has a first start vector for imaging one first structure (40) and an instruction for calculating a second start vector for imaging at least one second structure (40 ') from the first start vector. Method for producing a structure (50) in a layer (52) of a substrate to be structured by means of an electron beam exposure apparatus, wherein the structure (50) has an orientation with an angle (α) different from integer multiples of 45 ° to a reference coordinate (101) of a Reference coordinate system of the electron beam exposure apparatus, comprising: - Introducing the substrate, on the surface of a resist material (43) is applied, in the electron beam exposure system; - imaging a structure (40) from a number of equally sized elements (41) in the resist material (43), the elements (41) adjoining each other and staggered in a first direction, the structure (40) having a defined roughness of the structure edges having; - developing the resist material (43) to form a resist pattern; and - Transferring the resist pattern in the layer to be structured (52) of the substrate, wherein a substrate structure (50) is generated; wherein the process for transferring the resist pattern into the layer (52) of the substrate to be structured comprises an over-etching process that alters the lateral dimensions of the resist pattern and / or the substrate structure such that the generated substrate structure has an edge roughness reduced compared to the resist pattern generated by developing , Method according to Claim 8 , characterized in that the dimensions of the elements (41) and the amount by which adjoining elements (41) are offset from one another are selected such that substrate structures (50) are given a predetermined orientation Dimensions and given structure edge roughness result. Method according to Claim 8 , characterized in that the overetching process comprises etching the resist pattern. Method according to Claim 8 , characterized in that the over-etching process comprises an etching of the layer to be structured (52).

Images