DE102019206007A1 - Micromechanical component and manufacturing process for a micromechanical component - Google Patents

Abstract

The invention relates to a micromechanical component with a completely grown silicon substrate (10) with a first substrate surface (12a) and a second substrate surface (12b) directed away from the first substrate surface (12a), a medium space (40) structured into the silicon substrate (10). with a medium outlet opening (18) structured through the first substrate surface (12a), and a membrane (36) formed on the second substrate surface (12b), which delimits the medium space (40), an actuator device (38) of this type on the membrane (36 ) can be arranged or arranged so that the membrane (36) can be set into a deforming movement by means of the actuator device (38) in such a way that at least one medium present in the medium space (40) can be pushed out of the medium space (40) via the medium outlet opening (18) . The invention also relates to a manufacturing method for such a micromechanical component.

Description

The invention relates to a micromechanical component and a production method for a micromechanical component.

State of the art

Manufacturing methods for micromechanical components each with a medium space bounded by a membrane are known from the prior art, in which a recess in the form of the later medium space is structured in a first substrate and then the first substrate on a second substrate with the membrane formed thereon is firmly bonded. Such a method for producing a micromechanical component is for example in FIG DE 10 2014 214 532 B3 disclosed.

Disclosure of the invention

The invention creates a micromechanical component with the features of claim 1 and a production method for a micromechanical component with the features of claim 7.

Advantages of the invention

The present invention creates micromechanical components in which a medium present in the respective medium space of the micromechanical component comes into contact exclusively with silicon of the silicon substrate of the respective micromechanical component. The silicon of the silicon substrate of the respective micromechanical component, however, has a reliable resistance to a large number of media, which can be in the form of fluid / liquid, gel, gas and / or grains / microparticles. There is thus no need to fear contamination of the medium present in the medium space of the respective micromechanical component or damage / decomposition of the respective micromechanical component due to the medium present in its medium space. As will be explained below, the micromechanical components created by means of the present invention are therefore suitable for a large number of purposes for a comparatively long service life.

It is expressly pointed out here that the micromechanical components created by means of the present invention can also be produced relatively inexpensively. Furthermore, the micromechanical components can be designed with great design freedom.

In an advantageous embodiment of the micromechanical component, the silicon substrate is a silicon substrate that is completely grown in at least two silicon growth steps starting from an initial layer made of silicon. Such a completely grown silicon substrate has a reliable resistance to a large number of media, such as, for example, oxidative, organic, alkaline and / or acidic media. The silicon substrate encompassed by the embodiment of the micromechanical component described here thus withstands a large number of media present / filled in its medium space for a relatively long time, often (almost) indefinitely.

It is expressly pointed out here that the silicon substrate is free of bonding layers between its first substrate surface and its second substrate surface. Thus, the silicon substrate between its first substrate surface and its second substrate surface is also free of aluminum / germanium bond layers, compression bond layers, such as in particular gold / gold bond layers, seal glass bond layers and organic bond layers, such as special BCB bond layers. Such bonding layers are chemically attacked by a large number of media. Since the silicon substrate, however, is free of bond layers between its first substrate surface and its second substrate surface, there is no need for the at least one medium present in its medium space to be contaminated with at least one bond layer material or with decomposition of the medium space due to a chemical reaction of the bond layer with the at least one in the medium present in the medium space are feared.

In a further advantageous embodiment of the micromechanical component, in addition to the medium outlet opening, at least one further opening of the medium space is formed in the silicon substrate such that the medium space can be filled and / or emptied via the at least one further opening, the at least one further opening being through the first substrate surface, the second substrate surface and / or through at least one substrate side surface of the silicon substrate that extends from the first substrate surface to the second substrate surface. Filling or emptying the medium space of the embodiment of the micromechanical component described here is thus easily possible.

In addition, at least one screen structure can be formed on and / or within the at least one further opening. The introduction of undesired foreign particles into the medium space of the embodiment of the micromechanical component described here can be reliably prevented by means of the at least one screen structure.

For example, the micromechanical component can be a print head, an insulin pump, a laboratory chip, a sensor or a probe. The micromechanical component according to the invention can thus be designed / used in a variety of ways. It is pointed out, however, that the exemplary embodiments listed here for the micromechanical component according to the invention are not to be interpreted restrictively.

Executing a corresponding manufacturing method for a micromechanical component also creates the advantages explained above, the manufacturing method comprising the steps: forming a fully grown silicon substrate with a first substrate surface and a second substrate surface directed away from the first substrate surface, structuring a medium space in the silicon substrate, for which a medium outlet opening is structured through the first substrate surface, and forming a membrane on the second substrate surface, which delimits the medium space, wherein an actuator device can be arranged on the membrane in such a way that during a later operation of the micromechanical component formed with the actuator device the membrane is set into a deforming movement by means of the actuator device in such a way that at least one medium present in the medium space is exited from the medium space via the medium outlet opening is pushed out.

In an advantageous development of the manufacturing method, in addition to the medium outlet opening, at least one further opening of the medium space is formed in the silicon substrate so that the medium space can be filled and / or emptied via the at least one further opening, the at least one further opening through the first substrate surface , the second substrate surface and / or through at least one substrate side surface of the silicon substrate extending from the first substrate surface to the second substrate surface. The micromechanical component with the medium space that can be easily filled and / or emptied can thus be produced with comparatively little effort.

The silicon substrate is preferably completely formed starting from an initial layer made of silicon in at least two silicon growth steps. Silicon growth methods which can be used as the at least two silicon growth steps are known from the prior art. The silicon substrate is therefore comparatively easy to manufacture.

In an advantageous embodiment of the manufacturing method, at least one intermediate silicon growth step and a final silicon growth step are performed as the at least two silicon growth steps, the following method steps being performed one after the other: structuring of the medium outlet opening through the surface of the starting layer or later first substrate surface thinned back from the starting layer, covering a partial area of a side of the starting layer facing away from the first substrate surface with a first etch stop layer, carrying out the at least one intermediate silicon growth step by adding silicon on the side of the starting layer facing away from the first substrate surface or starting from one is grown from the intermediate product grown from the starting layer, wherein after each intermediate silicon growth step carried out, a partial area of the first substrate surface geric hteten side of the intermediate product is covered with a further etch stop layer, and etch stop walls are formed which connect the first etch stop layer and the at least one further etch stop layer to one another in such a way that the first etch stop layer, the at least one further etch stop layer and the etch stop walls form an etch stop delimitation which is a Surrounded with silicon-filled volume except for at least one etching opening, and forming the membrane by performing the last silicon growth step by adding silicon on the side facing away from the first substrate surface of the intermediate product grown from the starting layer in the at least one intermediate silicon growth step is grown up. As will be explained in more detail below, the embodiment of the manufacturing method described here can be carried out comparatively easily. An SOI wafer (silicone on isolator wafer) or a silicon substrate / silicon wafer can optionally be used as the starting material for the embodiment of the production method described here.

Preferably, after the formation of the membrane, the medium space is structured into the silicon substrate, which has grown completely in the at least two silicon growth steps starting from the starting layer, by etching the volume surrounded by the etch stop delimitation, and then the inner walls of the medium space from the first etching stop layer, which at least one further etch stop layer and the etch stop walls are exposed. The structuring of the medium space in the fully grown silicon substrate is thus easy to carry out, wherein, as will be explained in more detail below, advantageous shapes of the medium space can be implemented by means of the first etch stop layer, the at least one further etch stop layer and the etch stop walls.

For example, the first etch stop layer, the at least one further etch stop layer and the etch stop walls can be formed from silicon oxide, the silicon surrounded by the first etch stop layer, the at least one further etch stop layer and the etch stop walls being etched by means of xenon difluoride and / or sulfur hexafluoride. The structuring of the medium space in the completely grown silicon substrate is therefore possible without any problems, without undesired areas of the silicon substrate being etched at the same time.

If the first etch stop layer, the at least one further etch stop layer and the etch stop walls are formed from silicon oxide, the inner walls of the medium space are preferably exposed by removing the first etch stop layer, the at least one further etch stop layer and the etch stop walls in a gas phase etching process. Silicon oxide can be removed easily and reliably using a gas phase etching process. Thus, during a later operation of the micromechanical component produced by means of the embodiment of the production method described here, there is no need to fear contamination of the at least one medium present in its medium space with silicon dioxide.

Preferably, at least two intermediate silicon growth steps are carried out before the last silicon growth step. As will be explained in more detail below, various advantageous shapes of the medium space can be formed in this way without any problems.

As an advantageous further development, between the at least two performed intermediate silicon growth steps, at least one screen structure can be formed on and / or within the at least one further opening by growing silicon on the side of the intermediate product facing away from the first substrate surface. The formation of the at least one screen structure on and / or within the at least one further opening is thus easily possible. In addition, further design elements can be formed by the mentioned or further intermediate silicon growth steps, e.g. at least one support structure and / or at least one structure for preventing the propagation of pressure waves.

Figure list

• 1a bis 1e schematische Querschnitte durch Zwischenprodukte zum Erläutern einer ersten Ausführungsform des Herstellungsverfahrens für ein mikromechanisches Bauteil;
• 2 eine schematische Darstellung einer ersten Ausführungsform des mikromechanischen Bauteils;
• 3 einen schematischen Querschnitt durch ein Zwischenprodukt zum Erläutern einer zweiten Ausführungsform des Herstell u ngsverfahrens;
• 4 eine schematische Darstellung einer zweiten Ausführungsform des mikromechanischen Bauteils;
• 5 eine schematische Darstellung einer dritten Ausführungsform des mikromechanischen Bauteils;
• 6 eine schematische Darstellung einer vierten Ausführungsform des mikromechanischen Bauteils;
• 7 eine schematische Darstellung einer fünften Ausführungsform des mikromechanischen Bauteils;
• 8a bis 8c schematische Querschnitte durch Zwischenprodukte zum Erläutern einer dritten Ausführungsform des Herstellungsverfahrens;
• 9 eine schematische Darstellung einer sechsten Ausführungsform des mikromechanischen Bauteils;
• 10 eine schematische Darstellung einer siebten Ausführungsform des mikromechanischen Bauteils;
• 11 eine schematische Darstellung einer achten Ausführungsform des mikromechanischen Bauteils;
• 12a bis 12d schematische Querschnitte durch Zwischenprodukte zum Erläutern einer vierten Ausführungsform des Herstellungsverfahrens;
• 13 eine schematische Darstellung einer neunten Ausführungsform des mikromechanischen Bauteils; und
• 14 eine schematische Darstellung einer zehnten Ausführungsform des mikromechanischen Bauteils.

Further features and advantages of the present invention are explained below with reference to the figures. Show it:

• 1a to 1e schematic cross-sections through intermediate products to explain a first specific embodiment of the production method for a micromechanical component;
• 2 a schematic representation of a first embodiment of the micromechanical component;
• 3 a schematic cross section through an intermediate product to explain a second embodiment of the manufacturing process;
• 4th a schematic representation of a second embodiment of the micromechanical component;
• 5 a schematic representation of a third embodiment of the micromechanical component;
• 6 a schematic representation of a fourth embodiment of the micromechanical component;
• 7th a schematic representation of a fifth embodiment of the micromechanical component;
• 8a to 8c schematic cross-sections through intermediate products to explain a third embodiment of the production method;
• 9 a schematic representation of a sixth embodiment of the micromechanical component;
• 10 a schematic representation of a seventh embodiment of the micromechanical component;
• 11 a schematic representation of an eighth embodiment of the micromechanical component;
• 12a to 12d schematic cross-sections through intermediate products to explain a fourth embodiment of the production method;
• 13 a schematic representation of a ninth embodiment of the micromechanical component; and
• 14th a schematic representation of a tenth embodiment of the micromechanical component.

Embodiments of the invention

The figures described below can be interpreted both as representations of the respective micromechanical component and as representations of only one cell of the respective micromechanical component, the respective micromechanical component comprising several such cells and each of the cells of the micromechanical component each having the structures shown in the image . In particular, everyone can The micromechanical component described below have a plurality of such cells or can be produced with a plurality of such cells.

1a to 1e show schematic cross-sections through intermediate products to explain a first embodiment of the manufacturing method for a micromechanical component.

When carrying out the manufacturing method described here, a fully grown silicon substrate is obtained 10 with a first substrate surface 12a and one of the first substrate surface 12a away from the second substrate surface 12b formed by the silicon substrate 10 starting from an output layer 10a is completely formed from silicon in at least two silicon growth steps or epitaxial steps. At least one intermediate silicon growth step and a final silicon growth step are carried out as the at least two silicon growth steps. Each of the at least two silicon growth steps can be referred to as a silicon epitaxy step.

1a shows a cross section through the starting layer 10a made of silicon with the surface of the starting layer 10a present first substrate surface 12a . The starting layer 10a can for example be part of an SOI wafer (Silicone On Isolator Wafer), wherein the first substrate surface 12a to a semiconductor wafer 14th and one between the semiconductor wafer 14th and the output layer 10a insulating layer made of silicon 16 is aligned. The semiconductor wafer 14th can perform the functions of a “handling wafer” during the manufacturing process.

In the embodiment of the production method described here, a medium outlet opening is used 18th of a later medium space of the micromechanical component through the surface of the starting layer 10a present first substrate surface 12a structured by the medium outlet opening 18th through the output layer 10a is structured. The medium outlet opening 18th can for example through the output layer 10 etched / separated. The one with the medium outlet opening 18th formed starting layer 10a forms a first retaining wall 19th of the later medium space on its to the first substrate surface 12a aligned side.

In an alternative embodiment of the production method, only the semiconductor wafer (in this case consisting of silicon) can also be used 14th can be used as starting material. In this case, the medium outlet opening 18th by the later (from the starting layer 10a) thinned back first substrate surface 12a be structured by the medium outlet opening 18th in / through the semiconductor wafer 14th is structured and the first substrate surface 12a with the exposed medium outlet opening 18th later for back thinning the semiconductor wafer 14th is formed. As a back thinning of the semiconductor wafer 14th can, for example, be a chemical or physical grinding back of the semiconductor wafer 14th are executed.

Subsequently, a partial area becomes one of the first substrate surface 12a away facing side 20th the output layer 18th with a first etch stop layer 22nd covered. As will become clear from the following description, the first etch stop layer lays 22nd Positions and dimensions of inner walls of the later medium space on its to the first substrate surface 12a facing side firmly.

Thereafter, a first intermediate silicon growth step is carried out by adding silicon to the surface of the first substrate 12a away facing side 20th the output layer 10a is grown up. In this way, a first silicon region is created in the first intermediate silicon growth step 24 formed, which at least regionally in that of the first etch stop layer 22nd starting layer only partially covered 10a transforms. The first silicon area 24 thus becomes direct / compact on the output layer 10a grew up.

After the first intermediate silicon growth step, a partial area becomes that of the first substrate surface 12a away facing side 20th of the intermediate product with a second etch stop layer 26th covered. In addition, etch stop walls (not shown) are formed over which the first etch stop layer 22nd and the second etch stop layer 26th be connected to each other. The etch stop walls can be formed by structuring separating trenches through the first silicon region 24 and the separation trenches are filled with at least one etch stop material of the etch stop walls. The intermediate produced in this way is in 1b shown.

A second intermediate silicon growth step is then carried out by adding silicon to the surface of the first substrate 12a away facing side 20th des starting from the starting layer 10a grown intermediate product is grown up. On one of the starting layer 10a away from the side of the first silicon region 24 becomes a second silicon area in this way 28 grown, which at least regionally in the of the second etch stop layer 26th only partially covered first silicon area 24 transforms. Also the second silicon area 28 thus becomes direct / compact on the first silicon area 24 and the output layer 10a grew up. Of the second silicon area 28 forms a large part of a second retaining wall 30th of the later medium space on its to the second substrate surface 12b aligned side.

After the second intermediate silicon growth step, etch stop walls become 32 formed, which is through the second silicon area 28 extend. The formation of the etch stop walls 32 can by structuring separating trenches through the second silicon region 28 and then filling the separating trenches with at least one etch stop material of the etch stop walls 32 respectively. The intermediate product obtained is in 1c shown.

After forming the etch stop walls 32 becomes a third etch stop layer 34 on a partial area of the first substrate surface 12a away facing side 20th of the intermediate product formed. The etch stop walls 32 connect the second etch stop layer 26th and the third etch stop layer 34 together. The second etch stop layer 26th , the third etch stop layer 34 and the etch stop walls 32 place positions and dimensions of inner walls of the later medium space on its to the second surface 12b aligned side firmly. As in 1d can be seen, the first etch stop layer 22nd , the second etch stop layer 26th , the third etch stop layer 34 and the etch stop walls 32 formed such that the first etch stop layer 22nd , the second etch stop layer 26th , the third etch stop layer 34 and the etch stop walls 32 an etch stop limitation 22nd , 26th , 32 and 34 which form a volume filled with silicon except for at least one etching opening 35 surrounds. The etch stop limitation 22nd , 26th , 32 and 34 defines a shape and a spatial extent of the later medium space.

1d also shows forming a membrane 36 at that of the first substrate surface 12a away from the second substrate surface 12b by adding silicon in the final silicon growth step to that of the first substrate surface 12a away facing side 20th des starting from the starting layer 10a grown intermediate product is grown up. The silicon of the membrane 36 can in particular directly on the third etch stop layer 34 deposited, which ensures that the membrane formed in this way 36 limits the later medium space.

After the last silicon growth step has been carried out, the fully grown silicon substrate lies 10 finished before. To protect the second substrate surface 12b of the silicon substrate 10 A protective and / or insulating layer can be used during the further manufacturing process 37 such as an oxide layer on the second substrate surface 12b of the silicon substrate 10 be educated. The intermediate product obtained in this way is in 1d reproduced.

Optionally, an actuator device can now be used 38 so on the membrane 36 arranged / formed that in a later operation of the with the actuator device 38 trained micromechanical component the membrane 36 by means of the actuator device 38 is set into a deformation movement in such a way that at least one medium present in the later medium space passes through the medium outlet opening 18th is pushed out of the medium space. In the embodiment of 1a to 1e is the actuator device 38 for example a piezoelectric actuator device with at least one piezoelectric functional layer 38a , Electrodes 38b and at least one conductor track 38c with at least one contact area 38d . The at least one piezoelectric functional layer 38a can for example be a PZT functional layer (lead zirconate titanate). However, since the micromechanical component manufactured by means of the manufacturing method described here cannot be designed to a specific type of its actuator device 38 is limited, is not specified here on the actuator device 38 received.

In 1e is also the structuring of the medium space 40 into the silicon substrate 10 figuratively reproduced. This is done after the membrane 36 is already formed, the medium space 40 into that starting from the starting layer 10a fully grown silicon substrate 10 structured by that of the etch stop limitation 22nd , 26th , 32 and 34 surrounding silicon is etched. During the etching of the by the etch stop limit 22nd , 26th , 32 and 34 surrounding silicon are further areas of the silicon substrate 10 which should not be etched, especially the membrane 36 , by means of the at least one etch stop material of the etch stop delimitation 22nd , 26th , 32 and 34 reliably protected. After the etching of the etch stop 22nd , 26th , 32 and 34 surrounding silicon become the inner walls of the medium space 40 from the first etch stop layer 22nd , the second etch stop layer 26th , the third etch stop layer 34 and the etch stop walls 32 exposed. Contamination of at least one in the medium space 40 later filled medium through the at least one etch stop material of the etch stop delimitation 22nd , 26th , 32 and 34 thus need not be feared when the micromechanical component is in operation.

In an alternative embodiment of the manufacturing method described here, the medium space 40 first be freely etched before the formation of the actuator device 38 on / in the membrane 36 is started.

The etch stop limitation is preferred 22nd , 26th , 32 and 34 formed from silicon oxide (as their at least one etch stop material). The components of the etch stop limitation 22nd , 26th , 32 and 34 can thus each be formed by means of a comparatively low amount of work, such as, for example, by performing a thermal oxidation or by means of an oxide deposition. Another advantage of using silicon oxide as the (only) etch stop material of the etch stop delimitation 22nd , 26th , 32 and 34 is that that of the etch stop limitation 22nd , 26th , 32 and 34 In this case, the surrounding silicon can preferably be etched by means of xenon difluoride and / or sulfur hexafluoride, as a result of which the silicon to be etched can be reliably removed, and nevertheless (almost) no etching of the etch stop delimitation 22nd , 26th , 32 and 34 is to be feared. In addition, when using silicon oxide as the (only) etching material, the etch stop limitation 22nd , 26th , 32 and 34 the inner walls of the medium room 40 can be exposed comparatively easily by the etch stop limitation 22nd , 26th , 32 and 34 is removed in a gas phase etching process. As an alternative or in addition to silicon oxide, silicon nitride can also be used as an etch stop material for the etch stop delimitation 22nd , 26th , 32 and 34 be used.

In the manufacturing method described here, in addition to the medium outlet opening 18th than at least one more opening 42 and 44 of the medium room 40 such as a medium supply port 42 and a medium discharge port 44 , such in the silicon substrate 10 formed that the medium space 40 via the at least one other opening 42 and 44 can be filled / emptied. The at least one etching opening 35 is thus versatile. In the embodiment described here, the at least one further opening runs as an example 42 and 44 by at least one extending from the first substrate surface 12a to the second substrate surface 12b extending substrate side surface 12c and 12d of the silicon substrate 10 .

As an optional addition, a cap (not shown) on one of the medium space 40 away from the outside of the membrane 36 and the actuator device 38 attached. The capping can be firmly bonded, for example. In particular, sealing glass bonding and / or eutectic bonding using aluminum and germanium can be carried out as the bonding method for fastening the capping. Optionally, the semiconductor wafer 14th removed.

2 shows a schematic representation of a first embodiment of the micromechanical component.

This in 2 The schematically illustrated micromechanical component can be produced, for example, by means of the embodiment of the production method described above. The micromechanical component has a completely grown silicon substrate 10 with a first substrate surface 12a and one of the first substrate surface 12a away from the second substrate surface 12b on. As already explained above, the silicon substrate is 10 on starting from a starting layer 10a A silicon substrate completely grown from silicon in at least two silicon growth steps 10 . In addition, the silicon substrate is 10 between its first substrate surface 12a and its second substrate surface 12b free of bond layers.

In the silicon substrate 10 is a medium space 40 structured. The medium room 40 has one through the first substrate surface 12a structured medium outlet opening 18th on. The medium outlet opening 18th can also be referred to as a nozzle. Also is on the second substrate surface 12b a membrane 36 formed, which the medium space 40 limited. An actuator device 38 is like this on the membrane 36 arranged that the membrane 36 by means of the actuator device 38 can be set into a deformation movement in such a way that at least one in the medium space 40 present medium via the medium outlet opening 18th from the medium space 40 can be pushed out. A bulge in the membrane 36 in the medium room 40 can in particular a drop at the medium outlet opening 18th effect. The actuator device is preferably 38 on one of the media room 40 away from the outside of the membrane 36 arranged so that the actuator device 38 with the at least one in the medium space 40 does not come into contact with the present medium.

Due to the design of the silicon substrate 10 free of bond layers between its first substrate surface 12a and its second substrate surface 12b there is no need to fear that the at least one in the medium space 40 present medium chemically attacks a bond and thus leads to decomposition of the micromechanical component. Likewise, there does not have to be any contamination of the at least one in the medium space 40 present medium are feared by at least one bonding material of a bond. A high requirement for purity of at least one in the medium space 40 present medium, such as is frequently required for a medical / medical-technical or sensor-technical application of the at least one medium, can thus be reliably observed. The micromechanical component is therefore versatile, such as an insulin pump, a laboratory chip, a sensor or a probe. In the embodiment of 2 is the micromechanical Component of a printhead / printhead part, whereby even strongly alkaline or organic inks can easily be found inside the medium space 40 can be filled as one in the medium space 40 filled ink only the inner walls of the medium space 40 made of silicon and thus does not / hardly attack the micromechanical component. The formation of the medium space 40 made of (pure) silicon also simplifies the application of a continuous protective layer for media that attack silicon, since the protective layer only has to adhere to silicon and not to a bonding material.

The medium room 40 points on its to the first substrate surface 12a aligned side a first support wall 19th on whose perpendicular to the first substrate surface 12a aligned wall thickness through the layer thickness of the previous starting layer 10a is defined. At its to the second substrate surface 12b aligned side becomes the medium space 40 from a second retaining wall 30th and the membrane 36 limited, one perpendicular to the second substrate surface 12b aligned overhang of the second retaining wall 30th opposite the membrane 36 by the layer thickness of the previous second silicon area 28 is fixed. In addition to the medium outlet opening 18th is at least one more opening 42 and 44 of the medium room 40 (as a medium supply port 42 and as a medium discharge port 44 ) so into the silicon substrate 10 structured that the medium space 40 via the at least one other opening 42 and 44 can be filled and / or emptied. The at least one further opening runs by way of example 42 and 44 by at least one extending from the first substrate surface 12a to the second substrate surface 12b extending substrate side surface 12c and 12d of the silicon substrate 10 .

A cap is an optional addition 46 on one of the media room 40 away from the outside of the membrane 36 and the actuator device 38 attached. The capping is exemplary 46 by means of at least one bond connection 48 on the outside of the membrane 36 and the actuator device 38 attached.

With regard to other properties and features of the micromechanical component of the 2 reference is made to the manufacturing process described above.

3 shows a schematic cross section through an intermediate product to explain a second embodiment of the manufacturing method.

With the 3 The production process shown schematically is the medium space 40 at one to the medium outlet opening 18th adjacent area around a recess in the first support wall 19th trained exit opening vestibule 50 expanded by the first retaining wall 19th by means of an additional intermediate silicon growth step, which is carried out before the first intermediate silicon growth step, in order to apply one directly to the starting layer 10a grown up further silicon area 52 is reinforced. An etch stop layer can also be seen 54 and etch stop walls 56 , which is the later form of the exit opening vestibule 50 establish.

Regarding other properties and features of the manufacturing process of the 3 will affect the manufacturing process of the 1a to 1e referenced.

4th shows a schematic representation of a second embodiment of the micromechanical component.

This in 4th The micromechanical component shown schematically can, for example, by means of the 3 explained manufacturing process. The one to the medium outlet opening 18th adjacent area of the medium space 40 trained exit opening vestibule 50 provides volume for an advantageous eddy current in front of the medium outlet opening 18th . In addition, the exit opening antechamber enables 50 the formation of a very short medium outlet opening 18th without the stability of the first retaining wall 19th of the medium room 40 to restrict. In contrast to the embodiment of 2 the micromechanical component of the 4th also a medium outlet opening 18th with a smaller length perpendicular to the first substrate surface 12a on. A desired diameter and an advantageous shape of the medium outlet opening 18th are therefore used in the manufacture of the micromechanical component 4th easier and more precise to maintain, whereby a desired drop size from the medium outlet opening 18th emerging droplets, or a defined tear-off of the droplet, can be better ensured and bubbles and drying residues at the medium outlet opening 18th are more reliably suppressible. By means of the formation of the exit opening vestibule 50 as a recess in the first supporting wall 19th by means of the additional intermediate silicon growth step it is ensured at the same time that the first supporting wall 19th furthermore has advantageous stability.

With regard to other properties and features of the micromechanical component of the 4th reference is made to the embodiments described above.

5 shows a schematic representation of a third embodiment of the micromechanical component.

This in 5 The schematically illustrated micromechanical component differs from the previously described embodiment only in that its medium outlet opening is funnel-shaped 18th with one moving toward the first substrate surface 12a reducing diameter. The funnel-shaped design of the medium outlet opening 18th can be implemented using a KOH / potassium hydroxide etching process or a conical trench etching (tapered trench etching), for example.

With regard to other properties and features of the micromechanical component of the 5 reference is made to the embodiments described above.

6 shows a schematic representation of a fourth embodiment of the micromechanical component.

The in 6 schematically reproduced micromechanical component is at its at least one further opening 42 and 44 one throttle valve each 58 as constrictions at the respective further openings 42 and 44 educated. For this purpose, there is one to the medium outlet opening 18th or the exit opening vestibule 50 adjacent area of the medium space 40 an anteroom 60 of the medium room 40 as an (additional) recess in the first supporting wall 19th created by the first retaining wall 19th by means of an additional intermediate silicon growth step, which is carried out before the first intermediate silicon growth step, to create a further silicon region 62 is reinforced. The silicon of the at least one throttle valve 58 is deposited in the first intermediate silicon growth step, wherein the silicon of the at least one throttle valve is etched by means of previously formed etch stop layers and etch stop walls 58 while structuring the medium space 40 is prevented.

By means of the at least one throttle valve 58 can transmit vibrations from the diaphragm 36 the cell shown via the at least one in the medium space 40 filled medium on a membrane 36 a (not shown) adjacent cell are prevented. In this way, crosstalk between cells of a micromechanical component formed with a plurality of cells, which leads to an undesired increase in the size of a droplet from the medium outlet opening 18th could lead to a cell leaking droplets can be reliably prevented.

With regard to other properties and features of the micromechanical component of the 6 reference is made to the embodiments described above.

7th shows a schematic representation of a fifth embodiment of the micromechanical component.

This in 7th As a supplement to the embodiment described above, the schematically illustrated micromechanical component also has at least one screen structure 64 on and / or within its at least one further opening 42 and 44 on. The at least one screen structure 64 is preferably on and / or within the at least one further opening 42 and 44 formed by placing silicon on the of the first substrate surface between the at least two intermediate silicon growth steps carried out 12a away from the side of the intermediate product.

With regard to other properties and features of the micromechanical component of the 7th reference is made to the embodiments described above.

8a to 8c show schematic cross-sections through intermediate products to explain a third embodiment of the production method.

That by means of the 8a to 8c The micromechanical component shown schematically differ from the embodiment of FIG 2 in that the at least one other opening 42 and 44 through the second substrate surface 12b runs. As a further development of the embodiment of 1a to 1e becomes a capping 46 on that of the medium space 40 away from the outside of the membrane 36 and the actuator device 38 firmly bonded, in which a medium storage space 66 and a medium discharge space 68 are structured so that the at least one further opening 42 and 44 in the medium storage room 66 or in the medium discharge space 68 flows out. This is in 8a shown schematically.

8b shows the structuring of the medium space 40 and the gas phase etching, both processes after the packaging has been firmly bonded 46 via the medium storage room 66 through which at least one other opening 42 and 44 and via the medium drainage space 68 are executed. Then, as in 8c is shown, a silicon protective layer 70 deposited to the bond connections 48 before the at least one medium is filled into the medium space 40 to protect against wetting with the at least one medium. The application of the protective silicon layer 70 can for example be done by sputtering. Then the protrusions shown 72 the capping 46 can be removed by sawing or grinding back.

Regarding other properties and features of the manufacturing process of the 8a to 8c reference is made to the embodiments described above.

9 shows a schematic representation of a sixth embodiment of the micromechanical component.

This in 9 The schematically illustrated micromechanical component can, for example, by means of the manufacturing method of 8a to 8c be made. With regard to other properties of the micromechanical component of the 9 reference is therefore made to the statements relating to the embodiments described above.

10 shows a schematic representation of a seventh embodiment of the micromechanical component.

Also in the embodiment of 10 is at least one sieve structure 74 on and / or within the at least one further opening 42 and 44 educated. The at least one screen structure 74 can together with the membrane 36 in the final silicon growth step. (The at least one sieve structure 74 can be designed as a "membrane with holes".)

With regard to other properties and features of the micromechanical component of the 10 reference is made to the embodiments described above.

11 shows a schematic representation of an eighth embodiment of the micromechanical component.

With the 11 the schematically reproduced micromechanical component becomes its medium space 40 in addition to the membrane 36 nor from a damper membrane 76 limited. By means of the damper membrane 76 can be ensured that from the actuator device 38 with deformation of the membrane 36 generated pressure waves in the at least one in the medium space 40 present medium are attenuated and not transmitted to at least one neighboring cell.

Preferably the damper membrane is 76 a polyimide membrane. The polyimide of the damper membrane 76 can in this case after the formation of the actuator device 38 separated and structured.

With regard to other properties and features of the micromechanical component of the 11 reference is made to the embodiments described above.

12a to 12d show schematic cross-sections through intermediate products to explain a fourth embodiment of the production method.

In the manufacturing process of the 12a to 12d is used as a training in addition to the openings 18th , 42 and 44 another etching opening of its own 78 of the later medium space 40 educated. It also becomes the second substrate surface 12b except for the etching opening 78 / one the etching opening 78 surrounding area with a thick anti-etch layer 80 , such as an oxide layer, covered (see 12a) .

Then, as in 12b is shown schematically, the medium space 40 into the silicon substrate 10 structured. After structuring the medium space 40 and the gas phase etching becomes the etching opening 78 closed (see 12c ). This can be done for example by means of a local melting of silicon, such as by means of a laser sealing process (laser reseal), or by means of a material deposition. What remains is an etch seal 78a .

As in 12d can be seen, the bond connections 48 for attaching the cap 46 on one of the media room 40 away from the outside of the membrane 36 and the actuator device 38 only after structuring the medium space 40 and the gas phase etching. There is therefore no risk of the bond connections being damaged when the medium space is structured 40 or attacked during gas phase etching.

Regarding other properties and features of the manufacturing process of the 12a to 12d reference is made to the embodiments described above.

13 shows a schematic representation of a ninth embodiment of the micromechanical component.

This in 13 The schematically illustrated micromechanical component can, for example, by means of the manufacturing method described above 1a to 1e and 12a to 12d be made. With regard to the properties and features of the micromechanical component of the 13 reference is made to the embodiments described above.

14th shows a schematic representation of a tenth embodiment of the micromechanical component.

In contrast to the embodiments described above, in the case of the micromechanical component of the 13 the at least one other opening 42 and 44 through the first substrate surface 12a . The at least one screen structure 82 at the at least one other opening 42 and 44 can through the output layer 10a be structured.

With regard to other properties and features of the micromechanical component of the 14th reference is made to the embodiments described above.

The manufacturing methods explained above thus allow great design freedom when forming the respective micromechanical component, in particular when shaping its medium space 40 . In contrast to methods with bonding steps according to the prior art, there is no need for a modification of the medium space 40 the conventional need to pattern another wafer and bond the other wafer to an intermediate product.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102014214532 B3 [0002]

Claims (15)

Micromechanical component with: a fully grown silicon substrate (10) having a first substrate surface (12a) and a second substrate surface (12b) directed away from the first substrate surface (12a); a medium space (40) structured in the silicon substrate (10) with a medium outlet opening (18) structured through the first substrate surface (12a); and a membrane (36) which is formed on the second substrate surface (12b) and delimits the medium space (40); wherein an actuator device (38) can be arranged or arranged on the membrane (36) in such a way that the membrane (36) can be caused to deform by means of the actuator device (38) in such a way that at least one medium present in the medium space (40) passes through the Medium outlet opening (18) can be pushed out of the medium space (40). Micromechanical component according to Claim 1 wherein the silicon substrate (10) is a silicon substrate (10) that is completely grown in at least two silicon growth steps starting from an initial layer (10a) of silicon. Micromechanical component according to Claim 1 or 2 wherein the silicon substrate (10) is free of bonding layers between its first substrate surface (12a) and its second substrate surface (12b). Micromechanical component according to one of the preceding claims, wherein in addition to the medium outlet opening (18) at least one further opening (42, 44) of the medium space (40) in the silicon substrate (10) is designed so that the medium space (40) over the at least a further opening (42, 44) can be filled and / or emptied, and wherein the at least one further opening (42, 44) through the first substrate surface (12a), the second substrate surface (12b) and / or through at least one of the first substrate surface (12a) to the second substrate surface (12b) extending substrate side surface (12c, 12d) of the silicon substrate (10). Micromechanical component according to Claim 4 wherein at least one screen structure (64, 74, 82) is formed on and / or within the at least one further opening (42, 44). Micromechanical component according to one of the preceding claims, wherein the micromechanical component is a print head, an insulin pump, a laboratory chip, a sensor or a probe. Manufacturing process for a micromechanical component with the following steps: Forming a fully grown silicon substrate (10) having a first substrate surface (12a) and a second substrate surface (12b) directed away from the first substrate surface (12a); Structuring a medium space (40) in the silicon substrate (10), for which a medium outlet opening (18) is structured through the first substrate surface (12a); and Formation of a membrane (40) on the second substrate surface (12b), which delimits the medium space (40), wherein an actuator device (38) can be or will be arranged on the membrane (36) in such a way that during a later operation of the actuator device (38) formed micromechanical component, the membrane (36) is set into a deforming movement by means of the actuator device (38) in such a way that at least one medium present in the medium space (40) is pressed out of the medium space (40) via the medium outlet opening (18). Manufacturing process according to Claim 7 , wherein in addition to the medium outlet opening (18) at least one further opening (42, 44) of the medium space (40) is formed in the silicon substrate (10) in such a way that the medium space (40) via the at least one further opening (42, 44 ) can be filled and / or emptied, and wherein the at least one further opening (42, 44) through the first substrate surface (12a), the second substrate surface (12b) and / or through at least one extending from the first substrate surface (12a) to the second substrate surface (12b) extending substrate side surface (12c, 12d) of the silicon substrate (10) runs. Manufacturing process according to Claim 7 or 8th , the silicon substrate (10) being completely formed starting from an initial layer (10a) made of silicon in at least two silicon growth steps. Manufacturing process according to Claim 9 , wherein at least one intermediate silicon growth step and a final silicon growth step are carried out as the at least two silicon growth steps, and the following method steps are carried out one after the other: structuring of the medium outlet opening (18) through the surface of the starting layer (10a) first substrate surface (12a) present or later thinned back from the starting layer (10a); - Covering a partial area of a side (20) of the starting layer (10a) facing away from the first substrate surface (12a) with a first etch stop layer (22); - Carrying out the at least one intermediate silicon growth step by adding silicon on that side (20) of the starting layer (10a) or. That is directed away from the first substrate surface (12a) an intermediate product grown from the starting layer (10a) is grown, with a partial area of the side (20) of the intermediate product facing away from the first substrate surface (12a) being covered with a further etch stop layer (26, 34) after each intermediate silicon growth step carried out etch stop walls (32) are formed which connect the first etch stop layer (22) and the at least one further etch stop layer (26, 34) to one another in such a way that the first etch stop layer (22), the at least one further etch stop layer (26, 34 ) and the etch stop walls (32) form an etch stop delimitation (22, 26, 32, 34) which surround a volume filled with silicon apart from at least one etching opening (35); and - forming the membrane (36) by carrying out the last silicon growth step in which silicon is grown on the side of the intermediate product grown from the starting layer (10a) in the at least one intermediate silicon growth step which is directed away from the first substrate surface (12a) becomes. Manufacturing process according to Claim 10 , wherein after the formation of the membrane (36) the medium space (40) is structured into the silicon substrate, which has grown completely in the at least two silicon growth steps starting from the initial layer, by the volume surrounded by the etch stop delimitation (22, 26, 32, 34) is etched, and then the inner walls of the medium space (40) from the first etch stop layer (22), the at least one further etch stop layer (26, 34) and the etch stop walls (32) are exposed. Manufacturing process according to Claim 11 , wherein the first etch stop layer (22), the at least one further etch stop layer (26, 34) and the etch stop walls (32) are formed from silicon oxide, and wherein that of the first etch stop layer (22), the at least one further etch stop layer (26, 34 ) and silicon surrounding the etch stop walls (32) is etched by means of xenon difluoride and / or sulfur hexafluoride. Manufacturing process according to Claim 11 or 12 wherein the first etch stop layer (22), the at least one further etch stop layer (26, 34) and the etch stop walls (32) are formed from silicon oxide, and the inner walls of the medium space (40) are exposed by the first etch stop layer (22), the at least one further etch stop layer (26, 34) and the etch stop walls (32) are removed in a gas phase etching process. Manufacturing process according to one of the Claims 10 to 13 wherein at least two intermediate silicon growth steps are carried out before the last silicon growth step. Manufacturing process according to Claim 8 and one Claim 14 , wherein between the at least two performed intermediate silicon growth steps at least one screen structure (64) is formed on and / or within the at least one further opening (42, 44) by adding silicon on the side facing away from the first substrate surface (12a) (20) the intermediate is grown up.

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