DE102004015923A1 - Inspection method for resist structures on wafer surfaces uses test structures with test elements set out as a measuring scale and exposed to asymmetrical unbalanced capillary forces - Google Patents

Abstract

to Qualification of resist materials, developer solutions, rinsing solutions and development process parameters as well as for monitoring of processes in the development of photoresist layers (8) the occurrence of pattern collapse events (5) using test structures (3) automatically monitored. The test structures (3) have test elements arranged in the manner of a measuring scale (4) on during the development of asymmetric capillary forces of different magnitude (unbalanced capillary forces). Through the geometric structure the test elements (4) different differential capillary forces (ΔF) act on a resist web (21) of the test element (4). through Evaluation of pattern collapse events (5) in the test structures (3) is applied to that of the rinse solution (7) on the resist bridges (21) exercised Capillary force closed or the performance of the paint / developer process.

Description

The This invention relates to a method of inspecting resist patterns on wafer surfaces. The invention further includes test patterns for inspection of resist structures.

to Formation of structures on a wafer surface can be found in semiconductor process technology Photoresist materials for Photolithographic imaging method use. There will be a Process layer to be structured on an underlying substrate and a photoresist layer of the photoresist material on the process layer applied. The photoresist layer is determined by means of a photolithographic Mask exposed in sections. The photolithographic mask has transparent and opaque sections that correspond to one Template are arranged as trench lines and bar lines. Depending on Type of photoresist material as a positive or negative photoresist either the bridge lines opaque and the trench lines transparent Sections of the mask or the bridge lines transparent and the trench lines opaque sections of the mask. After exposure, the photoresist layer becomes developed, depending on Type of photoresist material, either the exposed or unexposed Sections are removed and from the photoresist a photoresist pattern is trained.

The Development of the photoresist material takes place by means of a developer solution, in either the exposed or unexposed portions of the photoresist layer are selectively soluble against the other sections. The chemical process will through a rinsing step stopped in which the developer solution is replaced by a rinsing solution. Subsequently The wafer is dried, such as by the sputtering solution is spun off. When drying of the wafer, the height decreases the rinse solution above the Wafer off until the rinse solution only still in trenches between resist strips emerging from the photoresist layer the photoresist structure is. In this case, act on the resist bridges from the rinsing solution capillary forces in different directions, which are partially not compensated against each other.

To In development, the photoresist pattern forms an etch mask for structuring the underlying process layer.

With increasing integration density will increase the width of the photoresist layer resulting resist webs lower. On the other hand, the photoresist layer provided with a sufficient layer thickness, as an etching mask for the underlying process layer can be used. The aspect ratio between the height a resist bar formed from the photoresist material and its Width is getting bigger and bigger. With smaller web width and higher aspect ratio is the mechanical stability reduced the resist bridges. As a result of the reduced mechanical stability resist resistors do not compensate for the effect on them, unilateral or asymmetric capillary forces (unbalanced capillary forces) during the Drying of the wafer occur, sometimes no longer stand and collapse. In this case, sections of the resist ribs incline in the direction of the stronger capillary force and fall over. Occurs such a so-called pattern collapse event a, that's the etching mask for the underlying process layer incomplete and one in a subsequent etching step structure produced in the process layer is faulty.

Based on the drawings of 2 the formation of capillary forces acting asymmetrically on resist bridges is explained.

In the 2A is a resist structure 2 on a substrate 1 educated. The resist structure 2 includes resist bridges 21 and between the resist bridges 21 trained trenches 22 . 24 , The trenches 22 . 24 are different high with a rinse solution 7 filled. The level of the rinse solution 7 in the ditch 24 differs by the filling height difference .DELTA.h from the levels in the trenches 22 , The ditch 22 standing rinse solution 7 exercise on each of the trench 22 adjacent Resiststege 21 by capillary action a tensile force F1 in the horizontal direction. The ditch 24 standing rinse solution 7 exercise on each of the trench 24 adjacent Resiststege 21 a tensile force F2 in the horizontal direction, the trench in the direction of the opposite 22 acting tensile force F1 is set opposite. The amount of tensile force F1, F2 is proportional to the level of the rinse solution 7 in each trench 22 . 24 , On a resist bridge 21 between two equal, but different high with the rinse solution 7 filled trenches 22 . 24 a resulting differential capillary force ΔF acts in the direction of the trench 22 with the higher level.

In the in the 2 B Example shown has the resist pattern 2 narrow trenches 22 with the trench width S1 and a wide ditch 23 with the trench width S2 on. The trenches 22 . 23 are up to the same level with a rinse solution 7 filled. The on a Resiststeg 21 in the direction of a ditch 22 . 23 acting capillary force of the rinse solution 7 is the lower, the farther the respective trench 22 . 23 is. The wide ditch 23 exercises on the adjacent resist bridges 21 a capillary force F2 and the narrow trenches 22 a magnitude larger capillary force F1, which is opposite to the capillary force F2. On one between two ditches 22 . 23 different width trained Resiststeg 21 one acts resulting difference capillary force .DELTA.F in the direction of the narrower trench 22 ,

There are approaches known to reduce the capillary forces acting on resist webs by appropriate choice of the developer solution, the rinse solution or the photoresist material or the process parameters. For example, a surfactant rinse process (SRP) is known for reducing capillary forces and suppressing pattern collapse events. The success of the measures taken is checked by a manually conducted electron microscopic inspection of the developed resist structures on the wafer surface, such as in the document US 20030183251 A1 (Kawakami et al.).

The review of the Success of the measures to reduce the capillary forces is also done by a process window comparison regarding wafers, with or without the measure were made. To become such a process window comparison Wafer exposed at different focus positions with different exposure levels and the formed resist structures on pattern collapse events examined. Be processed within the production line wafers each manually guided randomly examined by electron microscopy for pattern collapse events. The manual electron microscopic examination of samples is consuming and covers the wafers processed in the production line insufficient. In the production line, the number of Pattern collapse events due to manufacturing deviations, about the actual minimal structure width (critical dimension, CD) and deviations in the parameters of the development process, from wafer to wafer. In addition to the aforementioned, no means are currently known in the production line Wafer with pattern collapse events selectively weed out or rework before further processing. The qualification and monitoring of measures to reduce the capillary forces, such as surfactant rinsing processes, is expensive.

Of the Invention has for its object to provide a method available which simplifies the inspection of resist patterns on wafer surfaces. The task becomes processes for the optimization of development processes for suppression of pattern collapse events and qualifying wafers in the production line as well as test samples for the training of test structures for the Inspection of developed resist structures on wafer surfaces.

The Task is in a method of the type mentioned by solved the features mentioned in the characterizing part of claim 1. Further The object is achieved by the mentioned in claim 10 and 12 Method and by the test sample mentioned in claim 14 solved. Advantageous developments emerge from the respective subclaims.

A Resist layer is applied to a wafer surface. In a photolithographic process the resist layer is exposed in sections and thereby a Pattern illustrated on the resist layer. The template is designed as a mask with opaque and transparent sections, in the exposure passage between an exposure source and the Resist layer is arranged. The resist layer is by means of a developed liquid developer solution. In this case, from the resist layer according to the template a resist structure with resist bars and between the resist bars pronounced trenches educated. The developer solution is displaced by a rinse solution and thus stopping the development of the resist layer. The rinse solution is and examined the developed resist structure for pattern collapse events and evaluated.

According to the invention Template in a known place by one of the original ones Independent template, standardized test pattern added. From the one with the test sample exposed portion of the resist layer passes a test structure with a plurality of inspection elements with Resiststegen out. The resist strips of the test elements are during the Development of each opposing, asymmetric capillary forces different amount suspended. A resulting differential capillary force arises as the difference between the two on the resist bridge capillary forces acting in opposite directions.

The Resist webs are formed such that each different Quotient of the mechanical stability of the respective resist bar and the maximum capillary force acting on the resist bar result.

The Resist webs of the test elements are either with different resistance trained against pattern collapse events and will be during The development process in each case the same amount of differential capillary forces suspended.

Preferably, however, the test elements are designed with similar resist bridges of the same mechanical stability or resistance to pattern collapse events, to the diffe each of the different amounts.

The Evaluating the resist pattern on pattern collapse events in the consequence advantageously on the evaluation of the test structure or test elements limited, their placement within the resist pattern through the supplemented template given and known.

Within the test structures collapse the resist bars according to a predictable pattern and give about a Variety of throwers with different resist structures among themselves comparable images of pattern collapse events. While in Resist structures, as they are customary on wafers in the production line, always other resist bridges at different locations of the Collapse Resist webs collapse respective resist pattern collapse the test structure, if they actually collapse, always at the same and predictable place and in the same and predictable way.

Out the evaluation of the pattern collapse events within the test structure is based on the presence of pattern collapse events throughout wafer surface closed. The location of the test structures on the wafer surface is known. The time required for a manual inspection is significantly reduced and the validity of the inspection higher. A Automated inspection is possible.

In a preferred embodiment the method according to the invention For evaluation, electron microscopic image patterns become more intact test structures or test elements and / or test structures or test elements with pattern collapse events stored. When inspecting a wafer for pattern collapse events become its test structures scanned electron microscopically and with the stored image patterns about after a golden image concept compared. In the process, the stored image pattern is determined, which is most similar to the sampled image pattern and therefrom the presence of pattern collapse events in the scanned test structure or the sampled test element back closed.

In Preferably, the test elements are a test structure applied along a measuring axis on the wafer surface, wherein the test elements along the measuring axis in the manner of a measuring scale in each case a rising Differential Kapillarkraft are exposed. Such as a measuring scale trained test structure is suitable for automated detection in an advantageous manner and evaluation of the test elements in the course of an automated inspection of the wafer surface.

in the Ideally, after the removal of the rinse solution on the by the test elements formed a first range of test elements with pattern collapse events and a second section with intact test elements without pattern collapse events. The borderline between the two areas is a standardized, wafer independent Measure of that of the rinse solution during the Drying maximum applied to the resist structures Differenzkapillarkraft or for their relationship for mechanical stability the resist bridges. The evaluation according to the golden image process can be on individual test elements or on the entire test structure Respectively. In the latter case, a library of image patterns for all Combinations of collapsed resist bars created in the test structure. The image pattern from the library that would best be scanned Pattern matches, corresponds to a measure of the number the collapse ratio events on the wafer surface.

To a further preferred embodiment the method according to the invention the automated evaluation is done with a scatterometric Analysis of the test structures. In the process, the test structure becomes exposed, and evaluated the reflection pattern spectral analysis. The reflection pattern of collapsed resist lands differs from the reflection pattern of non-collapsed resist lands.

Especially with regard to the scatterometric analysis, the test elements become within a test structure each provided several times and periodically arranged side by side. The reflection pattern of collapsed resist webs is all the easier Reflectance patterns of non-collapsed Resiststege different, depending bigger the Number of identical test elements within the test structure is. The number of identical test elements within the same test structure is preferably three to ten.

With the method according to the invention let yourself also a statement about the homogeneity of the development process the entire wafer surface to meet. For this purpose, a plurality of identical test structures on the wafer surface distributed, approximately in the center of the wafer, on the middle Radius of the wafer, in the edge region of the wafer and at its outermost edge.

Within the test structure can the respective test elements with resist bars of different mechanical stability, for example different length and / or width, be provided, each of the same Differenzkapillarkraft get abandoned.

In Preferably, the resist ribs of the test elements are each with the same mechanical stability provided and each exposed to different differential capillary forces. For this purpose, the test elements each provided with at least one resist web of uniform width and a Differential capillary force through the distances and the difference of the widths on the long sides the Resiststege adjacent trenches specified.

In Particularly preferably, the test elements are each with two spaced apart by a mean trench of uniform width Resiststegen same width provided. Each of the middle Ditch opposite outer trenches of test elements are each with a second, larger width than the middle one Ditch training. The resist bars regularly fall in the direction of collapsing the middle trench, the higher Capillary force exerts. This advantageously results in a uniform pattern of collapse Resist ridges.

The inventive method for inspection of resist structures can be in a method for Optimization of development processes for the suppression of Pattern-Collapse events integrate. It concludes the term development process involves developing, rinsing and remove the rinse solution. On development wafers, first, resist patterns according to the above trained and inspected procedures described. The one undamaged A probe without pattern collapse events, to which the highest differential capillary force is detected, and the resist pattern is removed. By repeated repetition of the above steps with changed Process parameters, such as a different composition the developer solution or the rinse solution, is e.g. the optimal composition of the developer solution or the rinse solution as the one determines, when using the largest number of test elements remained intact.

are the inspection elements arranged to a measuring scale, then become the optimal process parameters as those determines, when using a boundary line between intact test elements and inspection elements with pattern collapse events is shifted the farthest towards the more sensitive test elements.

The inventive method for the inspection of resist structures can be used to verify Use wafers in the production line. This is first a Indicator test element determines its integrity on one for further processing Close suitable wafers leaves. A template with a containing an indicator test pattern element samples is imaged onto the resist layer. The resist layer is by means of a developer solution developed, wherein in the resist layer, the indicator test element is trained. The developer solution is displaced by a rinse solution. The Rinse solution is away. The indicator test element is automatically examined for pattern collapse events. Does that know Indicator test element If a pattern collapse event occurs, the resist structure is removed and the process is repeated from the application of the resist layer.

In Preferably, in addition to the indicator test element, a plurality of others test elements provided on the different from the rinse solution Differenzkapillarkräfte Contracts exercised to easily provide additional information about trends and to gain process windows of the development process.

The Test samples according to the invention for exposure masks for the design of test structures for inspection of developed resist patterns on wafer surfaces a plurality of test pattern elements on. Each test pattern element has at least one between two trench lines of different width arranged bridge line on. The ridge lines of the test pattern elements of a test pattern are each equal in length with parallel longitudinal sides and arranged aligned parallel to each other.

Prefers have the web lines of the test pattern the same width.

The Web lines correspond to resist webs by exposure the test pattern resulting from the resist layer test structure and are by type of the photoresist material as a positive or negative photoresist about opaque or transparent portions of an exposure mask. The trench lines correspond to trenches in the resist pattern and are more positive or negative according to the type of photoresist material Photoresist as about transparent or opaque sections of the exposure mask executed. Alternatively, the exposure mask can be used as a phase shift mask (Alt-PSM) or Halftone phase shift mask can be realized. Here are the Resist bridges and trenches through produces a phase difference in the mask. One more way for producing such structures is by e-beam or EUV lithographic Given procedure.

The trench lines are preferably completed within the test pattern or within the test pattern element, which advantageously during the development process in which the rinse solution is thrown off, as equal or comparable levels in the trenches of the test structures are enforced. By the drainage-free trenches standardize the behavior of the test elements with respect to pattern collapse events; in that the trenches within a test structure have essentially the same fill level during the entire development process.

The parallel arrangement of the test elements supports the automatic evaluation. The Resiststege are in the area of junctions the resist webs stabilized in other resist webs. Pattern-Collapse events Resist webs therefore preferably focus in the middle between each two junctions or branches. For decoupling the mechanical stability of the resist ribs as a display means for a resulting differential capillary force of geometric dimensions, which in turn are subject to manufacturing fluctuations, the length of the Web lines at least ten times the width of the web lines.

In a preferred embodiment has the test pattern according to the invention test elements each with two parallel ridge lines of equal width, wherein a median trench line disposed between the ridge lines has smaller width than that of the middle trench line at the web lines opposite outer trench lines. The evaluation of a test structure derived from such a test sample is simplified and leaves further conclusions the directionality of pattern collapse events.

following The invention is explained in more detail with reference to figures, wherein corresponding to each other Components are each denoted by the same reference numerals. Shown schematically in each case:

1 electron microscope photographs of top-down views of resist structures with pattern collapse events and without pattern collapse events;

2 Cross-sections of asymmetrically acting capillary forces exposed resist structures;

3 a plan view of a test pattern according to a first embodiment of the invention with a cross section through the corresponding resist pattern;

4 a plan view of a test pattern according to a second embodiment of the invention with a cross section through the corresponding resist pattern; and

5 a plan view of a test pattern according to a third embodiment of the invention with a cross section through the corresponding resist pattern;

The 2 was already explained at the beginning.

The two drawings of 1 are electron micrographs of a resist pattern 2 with resist bars 21 modeled, which is formed on a wafer surface. In the lower picture are Resiststege 21 fallen over a length of several hundred nanometers. These are pattern collapse events 5 , While the pattern collapse events 5 are documented in the lower shot, the absence of pattern collapse events in the upper shot does not conclude that there is no pattern collapse event outside of the shot range 5 present on the wafer surface. This would require an inspection of a much larger part of the wafer surface.

That in the 3 partial test samples 6 includes a plurality of test pattern elements 64 , Each test pattern element 64 includes a bridge line 61 a narrow trench line 62 on one long side of the bridge line 61 and a wide trench line 63 on the narrow trench line 62 opposite longitudinal side of the bridge line 61 , The bridge lines 61 as well as the wide trench lines 63 the test pattern element 64 are each the same length and the same width. The narrow trench lines 62 are for the respective test pattern elements 64 each provided with different widths. The width of the narrow trench lines 62 decreases from left to right.

The test sample 6 corresponds to the test structure shown above 3 ,

The test structure 3 is in a resist layer 8th on a substrate 1 is provided, trained. The test structure 3 includes a plurality of to the test pattern elements 64 corresponding test elements 4 , Every test element 4 includes one to the narrow trench line 62 corresponding narrow trench 42 , one to the jetty line 61 corresponding resist bridge 41 as well as a wide trench line 63 corresponding wide ditch 43 , The widths of the wide ditch 43 and the Resiststegs 41 the test elements 4 are the same. The width of the narrow trenches 42 takes place within the test structure 3 from left to right.

The resist bridges 41 the test elements 4 are during development different resulting capillary forces from the in the trenches 43 . 42 standing rinse solution 7 exposed. The on the Resststeg 41 acting resulting capillary force or Differential capillary force is in the right test element 4 the highest.

The amount of differential capillary force depends on the geometry of the test element, the level of the rinse solution 7 in the trenches 42 . 43 and the surface properties of the rinse solution 7 and the photoresist material. Due to the different width of the resist bridge 41 on both sides bounding trenches 42 . 43 act on the resist bridges 41 from the one in the trenches 42 . 43 standing rinse solution 7 outgoing capillary forces asymmetric. Relative to the same geometry, the amount of resulting differential capillary force is determined by the surface properties of the rinse solution 7 and the resist material.

With the test structure 3 the combination of developer solution, rinse solution, resist material and process parameters of the development process is determined, in which case within the test structure 3 the least number of pattern collapse events has occurred. The location of a boundary line between the inspection elements 4 with and without pattern collapse events is a measure of the number of pattern collapse events on the entire wafer surface and a measure of the suitability of the respective combination of developer solution, rinse solution, resist material and the parameters of the development process.

That in the 4 illustrated embodiment of the test pattern according to the invention differs from the Ausfüh tion of the 3 by a respective symmetrical structure of the test pattern elements 64 ' , Each test pattern element 64 ' includes two parallel bridge lines 61 ' same width. The two bridge lines 61 ' are through a mid-ditch line 62 ' separated from each other. On the middle ditch line 62 ' opposite longitudinal sides of the web lines 61 ' are each outer trench lines 621 . 622 educated. The test pattern elements 64 ' the test pattern 6 ' each differ by the width of the middle trench lines 62 ' from each other, which decreases in the illustrated embodiment from left to right. The distance between the inspection elements 4 can also be the width of a bridge line 61 ' be.

To the test sample 6 ' corresponds to a test structure 3 ' with inspection elements 4 ' which is shown in cross-section above. Every test element 4 ' includes two resist bridges 41 ' , one between the two resist bridges 41 ' arranged narrow trench 42 ' as well as outer trenches 431 . 432 ,

By the symmetrical arrangement simplifies the evaluation.

In the basis of the 5 Test structure shown fall in each case two adjacent outer trench 431 . 432 two adjacent test elements 4 the Indian 4 presented test structure together.

In both embodiments The narrowest mean trench line is narrower than the minimum trench width in the resist structure outside the test structure. This will cause at least one pattern collapse event within provoked by the test pattern and the evaluation of the test pattern facilitated.

To a further, not shown embodiment of the method according to the invention the automated evaluation takes place by means of the test structures trained functional structures. This is done with the developed Photoresist layer as a mask structured a functional layer, such as a layer of a conductive material. Through pattern collapse events the function of the functional structure is influenced. So surrendered yourself in a conductive Layer trace breaks corresponding to the locations the pattern collapse events. From the changed functionality of the functional Structure can be in a simple way to the occurrence of pattern collapse events back in the photoresist layer shut down.

1

substratum

10

wafer surface

2

resist structure

21

resist bridge

22

dig

23

further dig

24

narrow dig

3

test structure

4

A probe

41

resist bridge

41 '

resist bridge

42

narrow dig

42 '

narrow dig

43

further dig

431

further dig

432

further dig

5

Pattern-Collapse event

6

samples

61

ridge line

62

narrow grave line

63

width grave line

6 '

samples

61 '

ridge line

62 '

Means grave line

621

outer trench line

622

outer trench line

64

Prüfelementmuster

7

rinsing solution

8th

resist layer

F1

capillary force

F2

capillary force

.DELTA.F

resulting capillary force

.delta.h

Füllhöhendifferenz

S1

grave width

S2

grave width

Claims (21)

Method for inspecting resist structures on wafer surfaces with the steps - application of a resist layer ( 8th ) on a wafer surface ( 10 ); - exposure of the resist layer ( 8th ), with a template in the resist layer ( 8th ) is mapped; Developing the resist layer ( 8th ) by means of a developer solution, wherein from the resist layer ( 8th ) a resist structure ( 2 ) with resist bridges ( 21 ) and between the resist bridges ( 21 ) pronounced trenches ( 22 . 23 . 24 ) is formed; Rinsing the wafer surface ( 10 ), wherein the developer solution by a rinse solution ( 7 ) is replaced; - removing the rinse solution ( 7 ); and evaluation of the resist structure ( 2 ) on pattern collapse events ( 5 ); characterized by - completion of the sample by a test sample ( 6 ), wherein during development of the test sample ( 6 ) a test structure ( 3 ) with a plurality of test elements ( 4 ) with resist bridges ( 41 ) is formed such that for the resist ribs ( 41 ) in each case different quotients of their mechanical stability and on the resist webs ( 41 ) give maximum effective differential capillary force (ΔF) during rinsing; and - checking the test structure ( 3 ) of the resist structure ( 2 ) on pattern collapse events ( 5 ), whereby the placement of the test structures ( 3 ) on the wafer surface ( 10 ) is known. Method according to claim 1, characterized in that the resist ribs ( 41 ) of the test elements ( 4 ) are each provided with the same length and width and the amount of the respective Resiststeg ( 41 ) acting differential capillary force (.DELTA.F) in each case by the widths of at the longitudinal sides of the resist webs ( 41 ) of the test elements ( 4 ) subsequent trenches ( 42 . 43 ) is set; Method according to one of claims 1 or 2, characterized by automated testing of the test structures ( 3 ) in the course of the inspection. A method according to claim 3, characterized in that electron micrographically recorded image pattern of undamaged test elements ( 4 ) and / or test elements ( 4 ) with pattern collapse events ( 5 ) and when checking the image pattern of the inspected inspection elements ( 4 ) were recorded electron microscopically and compared with the stored image patterns. Method according to Claim 3, characterized in that scatterometrically recorded image patterns of intact test structures ( 3 ) and / or test structures ( 4 ) with pattern collapse events ( 5 ) and when checking the image pattern of the inspected inspection elements ( 4 ) are scatterometrically recorded and compared with the stored image patterns. A method according to claim 5, characterized in that in each case a plurality of identical test elements ( 4 ) are provided periodically next to each other. Method according to one of claims 1 to 6, characterized in that a plurality of test structures ( 3 ) on the wafer surface ( 10 ) is provided. Method according to one of claims 2 to 7, characterized in that the test elements ( 4 ) each with a Resiststeg ( 41 ) are provided uniform width and the amount of each acting Differenzkapillarkraft (.DELTA.F) by the width of the longitudinal sides of the respective resist bar ( 41 ) adjacent trenches ( 42 . 43 ) is given. Method according to one of claims 2 to 7, characterized in that the test elements ( 4 ) each with two through a middle trench ( 42 ' ) uniform width separate resist ribs ( 41 ' ) and the middle trenches ( 42 ' ) each on the longitudinal side of the resist ribs opposite outer trenches ( 431 . 432 ) are formed with a larger width, wherein the test elements ( 4 ) in the width of the middle trenches ( 42 ' ). Method for optimizing development processes for suppression of pattern collapse events ( 5 ) with the steps: 1) formation and inspection of resist structures ( 2 ) according to the method of any one of claims 1 to 9, wherein parameters of one of developing, rinsing and removing the rinse solution ( 7 ) comprehensive development process; 2) Determination of the intact test elements ( 3 ); 3) removing the resist pattern ( 2 ); 4) multiple repetition of steps 1) to 3), each with changed parameters of the development process; and 5) determining the optimal parameters as the parameters of the development process in which the largest number of test elements ( 4 ) remained intact. A method according to claim 10, characterized ge indicates that the test elements ( 4 ) of a test structure ( 3 ) depending on their sensitivity to pattern collapse events ( 5 ) are arranged in the manner of a measuring scale, and the parameters of the development process in which a boundary line between intact test elements ( 4 ) and test elements ( 4 ) with pattern collapse events ( 5 ) furthest in the direction of the test elements ( 4 ) greater sensitivity is shifted. Method for qualifying wafers in the production line, comprising the steps of: 1) determining an indicator test element whose integrity corresponds to a wafer suitable for further processing in the production line. 2) application of a resist layer ( 8th ) on the wafer surface ( 10 ) the wafer; 3) Imaging a test sample ( 6 ) in the resist layer ( 8th ); 4) developing the resist layer ( 8th ) by means of a developer solution, whereby from the test sample ( 6 ) a test structure ( 3 ) with the indicator test element ( 4 ) is formed; 5) replacing the developer solution with a rinse solution ( 7 ); 6) Remove the rinse solution ( 7 ); 7) automated evaluation of the resist structure ( 2 ) on pattern collapse events ( 5 ), where the placement of the indicator test element ( 4 ) is known; and 8) sorting out wafers with indicator test elements ( 4 ) with pattern collapse events ( 5 ). Method according to claim 12, characterized in that the test structure ( 3 ) with a plurality of test elements ( 4 ) and the test elements ( 4 ) are each exposed to different amounts in developing a differential capillary force (ΔF). Test sample for the design of test structures ( 3 ) for the inspection of a resist layer ( 8th ) developed resist structures ( 2 ) on wafer surfaces ( 10 ), where - the test sample ( 6 ) a plurality of test pattern elements ( 64 ), - the test pattern elements ( 64 ) at least one bridge line ( 61 . 61 ' ) uniform width and two each on opposite longitudinal sides of the web line ( 61 . 61 ' ) subsequent trench lines ( 62 . 63 ) of uniform width as transparent and opaque portions of one during exposure in the exposure step between an exposure source and the resist layer (FIG. 8th ), the trench lines (FIG. 62 . 63 ) of a test pattern element ( 64 ) have different widths, - the web lines ( 61 . 61 ' ) of the test pattern elements ( 64 ) each have the same length and the same width and - the one trench lines ( 62 ) of the test pattern elements ( 64 ) each have different widths, wherein the widths of the differently formed trench lines ( 62 ) differ by at least 1 percent to a maximum of 20 percent. Test sample according to claim 14, characterized in that the test pattern elements ( 64 ) along a measuring axis next to each other and according to the width of the differently formed trench lines ( 64 ) are arranged orderly. Test sample according to one of claims 14 to 15, characterized in that the trench lines ( 62 . 63 ) within the test sample ( 6 ) Are completed. Test sample according to one of claims 14 to 16, characterized in that the web lines ( 61 ) are straight. Test sample according to one of claims 14 to 17, characterized in that the length of the web lines ( 61 ) at least ten times the width of the web lines ( 61 ) is. Test sample according to one of Claims 15 to 18, characterized by test pattern elements ( 64 ) each with a web line ( 61 ) by trench lines ( 62 . 63 ) of different widths, the width of the trench lines ( 62 . 63 ) along the measuring axis transverse to the web lines ( 61 ) increases. Test sample according to one of Claims 15 to 18, characterized by test pattern elements ( 64 ) each with two parallel web lines ( 61 ) of equal width, one between the ridge lines ( 61 ) arranged middle trench line ( 62 ) has a smaller width than that of the middle trench line ( 62 ) at the bridge lines ( 61 ) opposite outer trench lines ( 621 . 622 ), where at the width of the middle trench lines ( 62 . 63 ) along the measuring axis transverse to the web lines ( 61 ) increases. Test sample according to claim 20, characterized in that the adjacent outer trench lines ( 621 . 622 ) each two adjacent test pattern elements ( 64 ) by a single trench line ( 621 ) are executed.