EP1381824B1 - Measurement of components that have been micro-galvanically produced, using a sample component by means of photoresist webs - Google Patents

Abstract

The inventive method for measuring micro-galvanically produced components (23') comprising a three-dimensional structure produced by deep lithography is characterised as follows: a single or multilayer component (23') is constructed by galvanic metal deposition, whereby the metal is deposited around a photoresist structure, which defines the desired orifice contours (40, 41, 42) of the component; during the micro-galvanic production process a photoresist area (45), which segments the structure of the component (23') in production in a targeted manner, is incorporated; at least the segmenting photoresist area (45) is dissolved out of the component (23') and the orifice structure of the segmented component (23') is measured in a contactless manner in the vicinity of a former photoresist web (46) of the photoresist area (45) by means of a measuring device.

Description

State of the art

The invention is based on a method for measuring mikrogalvanisch manufactured components after the genus of Main claim.

From DE 196 07 288 A1 are already such microgalvanized components known in the Shape of perforated discs at injection valves or whole generally for producing fine sprays, e.g. B. with large Spray angles, are used. The individual layers or functional levels of the perforated disc are doing through galvanic metal deposition built on each other (Multilayer electroplating). The layers are successively electrodeposited, so that the subsequent layer due to galvanic adhesion to the underlying Layer connects and all layers together then one form one-piece perforated disc. For better handling of a Variety of perforated discs in the application of various manufacturing process steps on a wafer are z. B. per perforated disc two positioning recordings in shape of circular through holes near the outer Limitation of the perforated disc provided, which extends over the extend entire axial height of the perforated disc. The time Successive construction of several electroplated layers is so relieved. The inner opening structure of a such mikrogalvanisch manufactured component is only with Help of destructive manufacturing processes (grinding) verifiable or measurable.

Advantages of the invention

The inventive method for measuring mikrogalvanisch manufactured components with the Characteristic features of the main claim has the Advantage that in a simple way the concrete Dimensions of the internal structure of the component checked and can be measured, so that in an advantageous way Information about the structure and contouring of the component fast, safe and reliable. To do this in the mikrogalvanischen production of the components in only few selected components that otherwise, for example in very large quantities on a wafer or utility are arranged specifically photoresist areas or webs installed, making these selected components in their Structure desired are interrupted. After leaching out of the photoresist are the internal structures of each However, the component is exposed in a simple manner and thus very simple non-contact and non-destructive vermessbar.

By the measures listed in the dependent claims are advantageous developments and improvements in the Main claim specified method possible.

It is particularly advantageous that angles, cavities, Rear spaces and offsets of the opening structure of the component and the layer thicknesses of the component contactless are measurable.

Advantageously, on a single wafer identical single or multi-layer components complete without interrupting the desired opening structure Photoresist areas along with the interrupting ones Photoresist areas having components by galvanic Metal deposition are produced. Should a remeasurement the components only randomly done, so it is meaningful, a ratio of broken components to complete components of the same type on a wafer of 3 to 5: 1000 set up. This is enough to get one Assessment of dimensional accuracy and quality of made components on the entire wafer.

drawing

An embodiment of the invention is in the drawing simplified and in the following Description explained in more detail. 1 shows a partially illustrated injection valve with a mikrogalvanisch manufactured component in the form of a Perforated disk, Figure 2 a mikrogalvanisch producible Perforated disk in a plan view, Figure 3 in Figure 2 illustrated perforated disc with an inner Photoresist area made, so the actual Perforated disk is interrupted, Figure 4 is a sectional view the interrupted perforated disc in the region of a lacquer edge according to arrows IV in Figure 3 and Figure 5 is a schematic Measuring and evaluation arrangement.

Description of the embodiment

In the figure 1 is a valve in the form of a Injector for fuel injection systems of mixture-compression spark-ignited internal combustion engines partially shown, which has a perforated disc 23, the an embodiment of a measurable according to the invention, represents mikrogalvanisch manufactured component. It should be noted that in the following even closer described perforated disc 23 not exclusively for the Use is provided to injectors; similar Components can also z. B. in painting nozzles, at Inhalers, in inkjet printers or in Freeze-drying process for injecting or injecting Liquids, such. As drinks, for atomizing Medicines are used. For the production of fine Sprays, z. B. with large angles, which are by means of Multilayer electroplating manufactured perforated discs 23 whole generally.

The perforated discs 23 themselves again provide only one Embodiment of a microgalvanized component Also microgalvanically produced components with completely from the described perforated disc 23 deviating forms, Contours, proportions and purposes can of course produced and measured according to the invention become.

The injection valve partially shown in Figure 1 has a tubular valve seat carrier 1, in the concentric to a valve longitudinal axis 2, a longitudinal opening 3 is formed is. In the longitudinal opening 3 is a z. B. tubular Valve needle 5 arranged at its downstream end 6 with a z. B. spherical valve closing body 7, to its circumference, for example, five flats 8 to Forward flow of the fuel are provided, fixed connected is.

The actuation of the injection valve takes place in known Way, for example, electromagnetic. To the axial Movement of the valve needle 5 and thus to open against the Spring force of a return spring, not shown, or Closing the injector serves a schematic indicated electromagnetic circuit with a magnetic coil 10, an armature 11 and a core 12. The armature 11 is with the valve closing body 7 facing away from the end Valve needle 5 by z. B. one by means of a laser produced weld and connected to the core 12th aligned.

To guide the valve closing body 7 during the Axialbewegüng serves a guide opening 15 of a Valve seat body 16, which in the downstream end of the valve seat carrier 1 in the longitudinal opening 3 through Welding is tightly mounted. The valve seat body 16 is with a z. B. pot-shaped perforated disc carrier 21 concentric and firmly connected, thus at least with an outer ring portion 22 directly on the Valve seat body 16 is present.

A mikrogalvanisch manufactured component, here the Perforated disk 23, is upstream of a through hole 20th arranged in the perforated disc carrier 21 such that it is the Through opening 20 completely covered. The connection Valve seat body 16 and disc holder 21 takes place for example, by a circumferential and dense, means a laser trained first weld 25th Der Perforated disk carrier 21 is connected to the wall of the longitudinal opening. 3 in the valve seat carrier 1, for example, by a circumferential and sealed second weld 30.

• Funktionsebenen mit über die Scheibenfläche konstanter Dicke,
• durch die tiefenlithographische Strukturierung weitgehend senkrechte Einschnitte in den Funktionsebenen, welche die jeweils durchströmten Hohlräume bilden (fertigungstechnisch bedingte Abweichungen von ca. 3° gegenüber optimal senkrechten Wandungen können auftreten),
• gewünschte Hinterschneidungen und Überdeckungen der Einschnitte durch mehrlagigen Aufbau einzeln strukturierter Metallschichten,
• Einschnitte mit beliebigen, weitgehend achsparallele Wandungen aufweisenden Querschnittsformen,
• einteilige Ausführung der Lochscheibe, da die einzelnen Metallabscheidungen unmittelbar aufeinander erfolgen.

The perforated disk 23 is clamped dimensionally accurate, for example, in a downstream cylindrical outlet opening 31 of the valve seat body 16 downstream of a valve seat surface 29 tapering in the shape of a truncated cone. The perforated disks 23 shown in FIGS. 2 to 4 are constructed in several metallic functional levels by means of electrodeposition (multilayer electroplating). Due to the deep lithographic, electroplating production, there are special features in the contouring, such. B.

• Functional levels with over the disk surface constant thickness,
• by the deep lithographic structuring largely vertical incisions in the functional planes which form the respective cavities through which flows (production-related deviations of about 3 ° with respect to optimally vertical walls can occur),
• desired undercuts and overlaps of the incisions by multilayer construction of individually structured metal layers,
• Incisions with any, largely axially parallel walls having cross-sectional shapes,
• one-piece design of the perforated disc, since the individual metal deposits are made directly to each other.

FIG. 2 shows an exemplary embodiment of a perforated disk 23 in a plan view, as for example on a Wafers or benefits produced hundreds of times side by side can be. The perforated disc 23 is as flat, circular component executed, the several, for example, three, axially consecutive Functional levels or layers has. From a bottom Function level 35 are started e.g. two more Function levels 36 and 37 built on it, where also in a single electroplating step several functional levels can be generated by means of so-called lateral overgrowth.

The upper functional level 37 has a rectangular shape Inlet opening 40 with the largest possible extent. With z. B. in each case the same distance to the valve longitudinal axis 2 and thus to the central axis of the perforated disc 23 and around this for example, are arranged symmetrically in the lower functional level 35 four square outlet openings 42 provided. The outlet openings 42 are at a Projection of all functional levels 35, 36, 37 into one plane with an offset outside the inlet opening 40. The Offset can be in different directions be different in size.

To a fluid flow from the inlet port 40 through to To ensure the outlet openings 42 is in the middle functional level 36 a channel 41 (cavity) formed, which represents a cavity. The one circular contour having channel 41 has such Size that he is in the projection the inlet opening 40 and the outlet openings 42 completely covered.

In Figures 3 and 4, the perforated disc with the same Contouring like the perforated disc 23 shown in FIG illustrated, but in a simple according to the invention measurable shape as interrupted perforated disc 23 '.

In the following sections, only in short form is the actual process for producing the perforated disks 23 explained according to the figures 2 to 4. The process steps the galvanic metal deposition for producing a Perforated disk can be removed from DE 196 07 288 A1.

Starting point for the procedure is a level and stable Support plate, the z. B. of metal (titanium, copper), Silicon, glass or ceramic can exist. On the Support plate is optionally at least one first Auxiliary layer on galvanized. It is about for example, an electroplating starting layer (eg Cu), the to the electric wire for the later micro electroplating is needed. The electroplating starter layer can also be used as Sacrificial layer serve to later a simple separation of the To allow perforated disk structures by etching. The Applying the auxiliary layer (typically CrCu or CrCuCr) happens z. B. by sputtering or by electroless Metal deposition. After this pretreatment of Carrier plate is a photoresist on the auxiliary layer (Photoresist) applied over the entire surface.

The thickness of the photoresist should be the thickness of the Metal layer, in the later following Galvanic process is to be realized, ie the thickness of the lower layer or functional plane 35 of the perforated disc 23rd The metal structure is to be realized with the help of a Photolithographic mask inverse in the photoresist be transmitted. One possibility is to use the Photoresist directly over the mask by UV exposure Exposure (UV depth lithography).

The ultimately resulting in the photoresist negative structure for later functional level of the perforated disc 23 becomes galvanic filled with metal (eg Ni, NiCo) (metal deposition). The metal lays down tightly by galvanizing Contour of the negative structure so that the given Contours are faithfully reproduced in it. To the Structure of the perforated disc 23 to realize the need to Steps from the optional application of the auxiliary layer repeated according to the number of layers desired be, with z. B. two functional levels in one Electroplating step are generated (lateral overgrowth). For the layers of a perforated disc 23 can also different metals are used, but only in can be used in each case a new electroplating step. Finally, the separation of the perforated discs 23 takes place. For this purpose, the sacrificial layer is etched away, causing the Lift off the perforated discs 23 from the carrier plate. After that will be the electroplating starting layers removed by etching and the Remaining photoresist from the metal structures removed.

Ideally, microgalvanised components, like the perforated discs 23, in very large numbers (e.g. > 1000 pieces) on a wafer or utility. To the separation of the perforated discs 23 of the support plate These are for their respective application for installation in front. The inner opening structure of such However, microgalvanized component is then not more accessible. For testing and measuring purposes, however, should at least randomly a very simple and cost-effective way to measure the components be created. Perforated discs 23, such as one in Figure 2 can be shown so far only with the help of destructive manufacturing processes are checked and measured become. This requires the components selected for remeasurement be embedded and polished in a complex manner. By grinding the completely manufactured components can disadvantageously create burrs that the Can falsify the measurement result. There is also one increased risk of deformation of the components to be measured when embedding and sanding.

Therefore, according to the invention directly in the mikrogalvanischen production of the components, here the Perforated discs 23, in only a few selected components 23 ' on the wafer (e.g., 3 to 5 out of 1000 components) Photoresist areas 45, which are also called Lackstege or Lackkerne can be characterized, built-in. Of the Installation of targeted photoresist areas 45 is about specially shaped masks on the selected components 23 ' made from the outset, so that the Metal structure starting from the lower functional level 35 already growing along this photoresist area 45. The selected components 23 'are thus in their Entire structure desired discontinuously produced (FIG. 3). After the dissolution of the photoresist region 45 are the internal structures of the respective component 23 'to simple Way exposed.

As can be seen from FIG. 3, it makes sense to use the Place photoresist area 45 in such a way that he can Opening structures cuts after manufacture to be measured. Thus, the photoresist region 45 in the hole disc 23 'shown in Figure 3 such built in that he has the functional levels 35, 36, 37 in the range the inlet port 40, the channel 41 and the Outlet openings 42 at the same time cuts.

Figure 4 shows a sectional view of the broken Perforated disk 23 'in the region of a paint edge 46 according to arrows IV in Figure 3. So this view does not clarify any Cut in the sense of a cutting up by the Perforated disk 23 ', but a side view of at the outset produced such perforated disc part. The on simple way exposed opening contour is like this very easily destructible measurable. typical Dimensions of a perforated disc 23, which are measured can, for example, the layer thickness a, the height h of the channel 41, the offset x of the inlet opening 40 and Outlet openings 42, the so-called back space z, so the over the outlet openings 42 projecting flow area of the channel 41, as well as the inlet flank angle 47 of Inlet opening 40 and the exit flank angle 48 of Outlet openings 42.

The present after separation components are in complete components 23 and broken components 23 ' sorted. The broken components 23 'become a Measuring device 50 is supplied. A schematic measuring and Evaluation arrangement is indicated in Figure 5. The non-contact measurement of the components 23 ', e.g. at one Not shown workpiece carriers are clamped, can with various measuring devices 50 take place. Are suitable For example, scanning electron microscope, profile projector with incident light, optical recording devices such as CCD camera or Infrared camera, microscope with position measuring system or Microfocus measuring system with laser scanning (UBM). The recorded Measured values are, for example, in an evaluation unit 51 processed and evaluated, whereby an assessment of the Dimensional accuracy and the quality of the manufactured components 23 is possible.

Claims (8)

1. Method for measuring microgalvanically produced components with a three-dimensional structure produced by depth lithography, characterized by the following method steps:

   construction of a single- or multilayered component (23') by galvanic metal deposition; the metal being deposited around a structure made of photoresist that prescribes the desired opening contour (40, 41, 42) of the component,

   in the process incorporation of a photoresist region (45) during the microgalvanic production, which region interrupts the structure of the component (23') to be produced in a targeted manner,

   stripping of at least the interrupting photoresist region (45) out of the interrupted component (23'), and

   contactless measurement of the opening structure of the interrupted component (23') in the region of a former varnished edge (46) of the photoresist region (45) by means of a measuring device (50).
2. Method according to Claim 1, characterized in that the photoresist region (45) is constructed in such a way that the opening structure of the component (23') is interrupted simultaneously in all planes (35, 36, 37).
3. Method according to Claim 1 or 2, characterized in that angles (47, 48), cavities (h), back-spaces (z) and offsets (x) of the opening structure of the component (23') can be measured contactlessly.
4. Method according to one of the preceding claims, characterized in that layer thicknesses (a) of the component (23') can be measured contactlessly.
5. Method according to one of the preceding claims, characterized in that a scanning electron microscope, a profile projector with reflected light, optical recording apparatuses such as CCD camera or infrared camera, a microscope with distance measuring system or a microfocus measuring system with laser scanning (UBM) are used as measuring devices (50).
6. Method according to Claim 5, characterized in that the recorded measured values are processed and evaluated in an evaluation unit (51).
7. Method according to one of the preceding claims, characterized in that structurally identical single- or multilayered components (23) are produced completely without photoresist regions (45) interrupting the desired opening structure together with the components (23') having the interrupting photoresist regions (45), by means of galvanic metal deposition on a wafer.
8. Method according to Claim 7, characterized in that the ratio of interrupted components (23') to complete components (23) of identical design on a wafer is 3 to 5 : 1000.

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