Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B81—MICROSTRUCTURAL TECHNOLOGY
  • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
  • B81B3/00—Devices comprising flexible or deformable elements, e.g. comprising elastic tongues or membranes
  • B81B3/0035—Constitution or structural means for controlling the movement of the flexible or deformable elements
  • B81B3/0051—For defining the movement, i.e. structures that guide or limit the movement of an element
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B81—MICROSTRUCTURAL TECHNOLOGY
  • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
  • B81B7/00—Microstructural systems; Auxiliary parts of microstructural devices or systems
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B81—MICROSTRUCTURAL TECHNOLOGY
  • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
  • B81B7/00—Microstructural systems; Auxiliary parts of microstructural devices or systems
  • B81B7/0032—Packages or encapsulation
  • B81B7/0067—Packages or encapsulation for controlling the passage of optical signals through the package
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B81—MICROSTRUCTURAL TECHNOLOGY
  • B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
  • B81C1/00—Manufacture or treatment of devices or systems in or on a substrate
  • B81C1/00015—Manufacture or treatment of devices or systems in or on a substrate for manufacturing microsystems
  • B81C1/00261—Processes for packaging MEMS devices
  • B81C1/00317—Packaging optical devices
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
  • G02B26/08—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light
  • G02B26/0816—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light by means of one or more reflecting elements
  • G02B26/0833—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light by means of one or more reflecting elements the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B81—MICROSTRUCTURAL TECHNOLOGY
  • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
  • B81B2201/00—Specific applications of microelectromechanical systems
  • B81B2201/04—Optical MEMS
  • B81B2201/042—Micromirrors, not used as optical switches
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B81—MICROSTRUCTURAL TECHNOLOGY
  • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
  • B81B2201/00—Specific applications of microelectromechanical systems
  • B81B2201/04—Optical MEMS
  • B81B2201/047—Optical MEMS not provided for in B81B2201/042 - B81B2201/045
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B81—MICROSTRUCTURAL TECHNOLOGY
  • B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
  • B81C2203/00—Forming microstructural systems
  • B81C2203/01—Packaging MEMS
  • B81C2203/0109—Bonding an individual cap on the substrate
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B81—MICROSTRUCTURAL TECHNOLOGY
  • B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
  • B81C2203/00—Forming microstructural systems
  • B81C2203/01—Packaging MEMS
  • B81C2203/0154—Moulding a cap over the MEMS device
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/49826—Assembling or joining

Definitions

• MEMS micro-mechanical
• MOEMS micro-optical systems
• components - such as acceleration sensors, rotation rate sensors, micromirrors - usually consist of very sensitive, partly freely movable microstructures (for example beams, grids, plates)
• the movable microstructures are still fixed and thus immovable with the substrate (carrier substrate), usually a wafer (carrier wafer), connected only by a so-called "release". Process, these microstructures are free to move. From this point on, the movable microstructures are particularly sensitive so that contamination or mechanical overloading can lead to the destruction or functional impairment of these microstructures and thus to the dysfunction of the component. For example, when a wafer is singulated, ie the sawing of a wafer into individual chips, the wafer surface comes about and thus the microstructures of the MEMS / MOEMS with particles and water in contact.
• the microstructures may be exposed to relatively high mechanical loads during a sawing process
• efforts are being made to carry out both the "release" process and measures, in particular for protecting the movable microstructures, before the substrate is singulated or divided.
• the invention relates to a housing for the encapsulation of micromechanical and micro-optical components, which are used in particular in mobile devices, and a method for producing such a housing, wherein the method also for the encapsulation of the MEMS / MOEMS at the substrate level, in particular on the wafer level, ie Separation process and thus before the fragmentation of the substrate, is suitable
• housings for encapsulating MEMS / MOEMS and methods for producing such packages, in particular wafer level packaging, are known in the semiconductor industry.
• the wafer carrier wafer
• the wafer becomes the MEMS / MOEMS with another wafer (lid wafer) with indentations of defined dimensions.
• the wafers are silicon wafers so that the wells in the lid wafer can also be easily and precisely fabricated using the proven processes of silicon technology subsequent singulation process, usually a sage process, then separate encapsulated chips are generated, without any risk of contamination for the MEMS / MOEMS Should the MEMS / MOEMS perform an optical function or should certain functions be performed?
• Parameters or physical variables of the MEMS / MOEMS are measured optically - for example, determination of the deflection by means of interferometer or by evaluation of video sequences - then it usually requires an optically transparent cover substrate
• WO 2004/1068665 describes a wafer-level packaging method for MOEMS which provides a glass cover substrate. Before the encapsulation process, however, the wafer is separated with the MOEMS. The resulting separate un-encapsulated chips (DIEs) are placed on a new substrate placed, assembled, contacted and then encapsulated
• US6146917 describes a MEMS / MOEMS wafer-level packaging process in which a truncated wafer of silicon or glass is bonded to the carrier wafer by fusion bonding or anodic bonding, resulting in a hermetically sealed package
• the required 50 to 1 50 micron deep wells in the lid wafer made of silicon can be done by wet chemical etching using KOH solution and is also transferable to glass wafers
• a lidded wafer glass wafer anodically bonded to the silicon wafer support is sufficient.
• a second lid wafer for the second side of the carrier wafer opposite the first side of the carrier wafer is provided on the first side of the carrier wafer.
• the present invention has for its object to overcome the disadvantages of the prior art and to provide a housing, which is particularly suitable for optical applications, has a mechanical overload protection and can be produced at the substrate or wafer level
• Claim 24 specifies a method for producing the housing according to the invention
• the housing according to the invention serves for the encapsulation of one or more micromechanical and / or microoptical components and has Carrier substrate, with at least one micromechanical and / or micro-optical
• the support substrate and the cover substrate are connected to one another, preferably cohesively in connection, and form one or more cavities, which at least partially encloses the at least one micromechanical and / or microoptical component
• the at least one micromechanical and / or micro-optical component facing side of the lid substrate has at least one optical window and at least one mechanical stop
• a housing for encapsulating MEMS / MOEMS, in particular movable MEMS / MOEMS, should as a rule provide at least protection against contaminants and at the same time not impair the mechanical and / or optical functionality of the MEMS / MOEMS.
• a cover substrate can act as the housing If the functionality of the MEMS / MOEMS is not limited to movements in or parallel to the carrier substrate plane, but also provides for movements perpendicular to the carrier substrate plane, the housing must ensure the MEMS / MOEMS appropriate freedom of movement
• the lid substrate may have recesses which, in conjunction with the carrier substrate, form cavities around the MEMS / MOEMS, so that the functionality of the MEMS / MOEMS is not restricted
• the housing according to the invention has one or more integrated mechanical stops which preferably project from the cover substrate in any direction in the direction of the MEMS / MOEMS.
• the protuberances project out of the cover, in particular from the surface of the optical window facing the MEMS / MOEMS prevents areas of the MEMS / MOEMS with the largest deflection amplitudes - and thus, for example during rotational movements at the highest speed - from abutting the cover substrate.
• areas of the MEMS / MOEMS for provides contact with the bumps that are best suited, for example, because their maximum vertical
• Speed is low compared to other areas, they have no active function or represent no active areas and / or these areas are designed to be particularly mechanically stable This reduces the risk of damage to the microstructures and thus the MEMS / MOEMS in case of mechanical overloading
• the mechanical stops should not restrict the functionality or the desired working range of the MEMS / MOEMS, wherein the distance between the mechanical stops and the areas of the MEMS / MOEMS intended for contact with the stops should preferably be as small as possible
• the housing also has to perform optical functions. Due to the outstanding stops, the housing according to the invention offers the advantage that, in the case of mechanical overstresses, only the MEMS / MOEMS contacts the stops. Other areas of the lid substrate do not come into contact with the MEMS / MOEMS. This will make the other areas of the
• Cover substrate which act as optical windows, for example, not damaged or impaired in their functionality.
• an optical window is understood as meaning a region of the housing which is suitable for any wavelengths and / or wavelength ranges of electromagnetic radiation, in particular those through which the device is to be encapsulated
• MEMS / MOEMS radiation to be processed and thus the radiation used in the application - from the infrared, visible (light) and ultraviolet frequency range permeable, especially transparent, and also usually meets high quality requirements in particular to the surface roughness, the flatness and the plane parallelism. Furthermore, these regions should preferably have a homogeneous material structure.
• a typical micro-optical device is the micromirror, which can be used in the video laser projection as a scanning mirror, for example, to deflect an incident laser beam.
• the laser beam should be scattered and deformed by the housing as little as possible.
• the lid substrate is provided with depressions, so that the carrier substrate and lid substrate generally completely surround the MEMS / MOEMS after their connection.
• depths are between about 50 ⁇ m and 900 ⁇ m sufficient for the recesses.
• Such depressions are useful, for example, for relatively large movably suspended micromirrors, which may have a diameter of 10 mm
• Tilting of such a dimensioned micromirror by 10 ° about its central axis leads to a maximum directed from the substrate plane deflection of almost 870 microns
• the housing terminates the MEMS / MOEMS hermetically sealed from the environment so that a certain atmosphere can be set in the housing.
• This provides particularly good protection against contaminants, thereby minimizing the risk of dysfunction of the encapsulated MEMS / MOEMS
• an atmosphere independent of the environment can be set in the cavities.
• a hermetically sealed encapsulation already results from a combination of carrier substrate and a
• Cover substrate can be achieved, it is necessary in volume micromechanically fabricated MEMS / MOEMS, which have partially completely through the carrier substrate etched microstructures, at least a second lid substrate, which is opposite to the first side of the carrier substrate, which is in communication with the first lid substrate second side of the carrier substrate is connected, so that the carrier substrate is provided on both sides with cover substrates
• a housing internal pressure below the atmospheric air pressure is preferred.
• a housing internal pressure of from about 10 3 mbar to about 1 mbar is particularly preferred.
• the cavities are filled with a gas, in order thereby to influence certain properties of the MEMS / MOEMS in a targeted manner.
• gases are dry and non-electrically conductive, with those for the housing and the MEMS / materials used MOEMS not react chemically and have the requisite transparency, examples which may be inert gases such as noble gases, nitrogen or SF called 6 for example, in applications where heat should be quickly dissipated to the housing and the environment, argon used as Gehauseatmospharengas, because argon is electrically non-conductive, but still has a relatively high thermal conductivity Moreover, the diffusion tendency of argon is so low that long-term stable pressure conditions in the housing are possible
• the carrier substrate used is preferably silicon wafer, since the processes of silicon technology are mature and well controlled
• a housing is necessary, which at least partially corresponds to the above-mentioned requirements for an optical window as well as mechanical as well as the optical functionality of the encapsulated MEMS / MOEMS as little as possible or not impaired
• the cover substrate preferably contains or consists of glass and / or a glass-thin material.
• Glass-like materials are materials according to the invention which, because of their thermodynamic properties (amorphous structure, glass transition temperature), are glaziers, although their chemical composition differs from that of silicate glass. Examples are here Particularly suitable glasses are silicate glasses, in particular borosilicate glasses, since borosilicate glasses are very resistant to chemicals and temperature. The temperature resistance and insensitivity of the borosilicate glassware to sudden temperature fluctuations are a consequence of their low levels of thermal stability and insensitivity
• the optical windows of the housing should have a flatness and / or parallelism deviation less than one quarter of the wavelength of the electromagnetic radiation used in the application, typically wavelengths from the ultraviolet to the infrared wavelength range (for example, between about 200 nm and about 15 .mu.m) find application Accordingly, with long wavelength light with wavelengths under 720 nm Values for the evenness and / or parallelism deviation of less than 180 nm are advantageous When using short-wavelength light with wavelengths below 440 nm, the demands on the optical windows increase, so that values for the evenness and / or plane parallelism deviation of less than 1 10 nm are preferred Optical windows that meet these requirements will cause lower
• Deviations and a smaller beam expansion of the optical beam path which leads to a lower distortion of the optical signals
• the quadratic surface roughness of the optical window should be as low as possible, preferably less than 15 nm, particularly preferably less than 5 nm. In this way, in particular, the scattering caused by the cover substrate can be reduced
• finishing layers are, for example, antireflection coatings which reduce reflections at the optical windows and thus radiation losses.
• antireflection coatings can be formed, for example, by layer systems Magnesiumfluo ⁇ d and titanium oxide or Sihziumdioxid and titanium dioxide realize
• antistatic layers that minimize electrical charging of the lid substrate often find use in antistatic layers
• Particularly suitable material for optical applications is ITO (indium tin oxide), since it has a high electrical conductivity and has a high transparency over a wide frequency range
• reflection layers for example metal layers
• reflection layers can be applied, which after structuring form locally reflecting regions, for example to spatially confine an incident light beam (aperture function) or to form a static deflection mirror in proximity to the optical windows.
• Preferred finishing layers are furthermore used Absorber layers that absorb electromagnetic radiation of certain wavelengths or entire wavelength ranges
• the method according to the invention for producing a housing for encapsulating micromechanical and / or microoptical components comprises the following steps: providing a carrier substrate with at least one micromechanical and / or microoptical component providing at least one lid substrate having at least one optical substrate
• Window and at least one mechanical stop comprises connecting the carrier substrate with the at least one lid substrate such that the carrier substrate and the at least one lid substrate form at least one cavity which at least partially encloses the at least one micromechanical and / or micro-optical component
• the inventive method is used for the encapsulation of MEMS / MOEMS, which are usually applied or arranged on a carrier substrate.
• a Sihziumwafer is used as a carrier substrate on which the MEMS / MOEMS to be encapsulated are produced by surface micromechanical or volume micromechanical processes
• the encapsulation furthermore requires a cover substrate which is usually transparent to the electromagnetic radiation used in the application even before the optical windows and the mechanical stops are produced, at least in some areas, generally in their entirety.
• a cover substrate which is usually transparent to the electromagnetic radiation used in the application even before the optical windows and the mechanical stops are produced, at least in some areas, generally in their entirety.
• the cover substrate is usually patterned Window and the mechanical stops generated
• glass substrates As described above, different glasses and certain glass-thin plastics are suitable as cover substrates.
• Various structuring methods used in silicon technology can also be used for glass substrates.
• the wells can be etched with HF solution.
• wet-chemical structured etching of glass substrates generally leads to considerable Inhomogeneities with regard to the etched depth within the etched surfaces (inadequate plane parallelism of the surfaces) and, in addition, to strongly roughened surfaces, and although the more deeply etched the deeper.
• such a structured etching of glass substrates generally leads to considerable Inhomogeneities with regard to the etched depth within the etched surfaces (inadequate plane parallelism of the surfaces) and, in addition, to strongly roughened surfaces, and although the more deeply etched the deeper. In general, such a structured
• Lid substrate unsuitable for optical applications.
• the surface quality of the glass substrate is mainly determined by the surface quality of the molding substrate.
• the optical windows are at least partially provided with an antireflection coating and / or an antistatic layer and / or a reflection layer and / or an absorber layer, whereby the optical functionality of the housing can be improved.
• Cover substrate connected to each other, so that the carrier substrate and the at least one lid substrate form at least one cavity which at least partially encloses the M E M S / M O E M.
• the carrier substrate and the at least one cover substrate are formed by anodic and / or eutectic bonding and / or glass fritting.
• Bonding method commonly used bonding techniques in particular for hermetically sealed encapsulation of components. Eutectic bonding is particularly preferred when energy absorbed by the MEMS / MOEMS, for example radiant energy, is to be dissipated onto the lid substrate
• a very specific atmosphere for example, a pressure below the atmospheric air pressure, more preferably between about 10 3 mbar and about 1 mbar, and / or an inert gas filling,
• argon - be produced in a hermetically sealed housing It is therefore preferred connecting techniques that can ensure a stable atmosphere in the housing
• the inventive method is particularly preferably used at the wafer level as a wafer-level packaging method, which can encapsulate several MEMS / MOEMS simultaneously and thus a time-saving and effective encapsulation is given
• the method is preferably used for the encapsulation of movable micromirrors and / or micromirror arrays
• FIG. 1 shows a micromachined micro-mirror 12 which is encapsulated with two transparent lid wafers 2, 3 and which is suspended on torsion springs 11
• Fig. 2 shows one with a transparent 2 and a non-transparent plane
• Lid wafer 3 encapsulated volume micro-mechanically micromirror 12, which is suspended from torsion springs 1 1
• FIG. 3 shows a volume micromechanically produced micromirror 12 which is encased in torsion springs 11 with a transparent 2 and a non-transparent lid wafer 3 provided with a depression
• FIG. 4 shows the sequence of steps for producing a lid wafer 2 by means of the glass flow method
• FIG. 1 a cover wafer 2 (top lid wafer 2 on the front side of the carrier wafer and bottom lid wafer 3 on the back side of the wafer is shown in FIG.
• the carrier wafer 1 for contacting the lid wafers 2, 3 has a frame-shaped closed planar contact area 7 around the micromirror 12.
• a correspondingly dimensioned closed-form planar contact area 7 is provided in the lid wafers as a counter contact area
• the top lid wafer 2 contains depressions 4 which, in conjunction with the carrier wafer 1, form the cavities 5 necessary for the movements of the micromirror.
• the micromirror 12 suspended on torsion springs 11 can have a diameter of 10 mm, for example Micromirror 12 by 10 ° are depressions 4 in the top lid wafer 2 of more than 870 microns necessary so that the deepest wells 4, measured from the contact areas 7 to the bottom of these wells 4, about 900 microns amount
• the bottom of the deepest wells 4 form simultaneously the areas that act as optical window 13
• the depth of the recesses 4 is dimensioned so that the stops to the undeflected torsion springs 1 1 have a vertical distance between 1 .mu.m and 50 .mu.m
• the stops 8 have no optical function
• the top lid wafer 2 thus has three different structure heights for creating the optical windows 13, the stops 8 and the contact areas 7
• the optical windows 13 and the planar side of the top lid wafer 2 facing away from the micromirror 12 are provided with an antireflection coating 10 of a layer system of magnesium fluoride and titanium dioxide
• the bottom lid wafer 3 is not structured and hermetically seals the cavity 5 around the micromirror 12.
• the bottom lid wafer 3 is also provided with antireflection coatings 10 on both sides Irradiate back of the micromirror 12 and use the reflected beam to determine the mirror position
• Mechanical stops 8 are not present in the bottom lid wafer 3, but can be provided in a further embodiment in order to ensure overload protection in both directions perpendicular to the carrier wafer plane If the bottom lid wafer 3 does not have optical functionality, a commercially available silicon wafer can be used, as shown in FIG. 2 and FIG.
• the bottom lid wafer 3 is provided with a recess 16 in order to enlarge the cavity 5 about the micromirror 12. This is necessary if the micromirror 12, as in the embodiment shown here, stiffening structures 1
• the recess 16 in the bottom lid wafer 3 is used to form a getter material 14 (for example, zirconium alloys), for reducing static and dynamic deformations and / or drive structures 15, for example for vertical drives and / or wafer thickness. Titanium), which serves for long-term maintenance of a vacuum within the cavity 5 to deposit there
• a further embodiment according to the invention provides further depressions 6 in the top lid wafer 2 outside the cavity 5 enclosing the micromirror 12. These depressions 6 enclose the connection fields (pads) 9 after the connection of carrier wafer 1 and top lid wafer 2
• connection fields pads
• buried conductor tracks below the contact region 7 between carrier wafer 1 and top lid wafer 2 can emerge laterally from the cavity 5 enclosing the micromirror 12 laterally to the connection fields 9 by a sagging step which does not involve the complete wafer assembly of carrier wafer 1 and lid wafers 2, 3 but only the top lid wafer 2 in the area of the connection fields 9, it is possible to make the connection fields 9 accessible without impairing the atmosphere in the cavity 5 enclosing the micromirror 12. This has the advantage that even before the For example, functional tests or measurements on the finished encapsulated micromirror 12 can be performed
• borosilicate glass glass wafers After providing the carrier wafer 1 made of silicon with the micromirror 12 to be encapsulated, for example, two glass wafers of borosilicate glass are provided which serve as top 2 and bottom lid wafers 3.
• the borosilicate glass glass wafers have, for example, a thickness between 0.5 mm and 3 mm, depending, among other things, on the required stability
• FIG. 4 shows the sequence of steps for structuring the top lid wafer 2 by means of a glass flow method.
• the structures of a forming wafer 21 are shaped or transferred onto the top lid wafer 2
• the basis for the molding wafer 21 is a single-sided polished silicon wafer. This molding wafer 21 remains unchanged in the regions through which the optical windows 13 are formed, so that the original surface quality of the polished silicon wafer 21 is preserved. In the regions in which the contact regions 7 of the top lid wafer 2, uniformly deep trenches 23 are etched into the forming wafer 21. The etching depth of these trenches 23 approximately determines the depth of the cavity 5
• etch processes come into question Very homogenously over the entire mold wafer 21, this can be achieved, for example, by time-controlled wet-chemical etching in potassium hydroxide (KOH) or TMAH (tetramethylammonium hydroxide).
• KOH potassium hydroxide
• TMAH tetramethylammonium hydroxide
• Plasma-trimmed dry etching processes can also produce such trenches 23 with high precision, but usually provided that the width of the trenches 23 is uniform throughout To a maximum of homogeneity of the trench depth and at the same time a minimum
• Roughness of the trench bottom (27) can be used for the mold wafer 21 instead of the standard silicon wafer, a SOI wafer (silicon on insulator - wafer) of appropriate thickness, the trenches 23 are etched to the hidden oxide layer
• the top wafer 2 is anodically bonded to the mold wafer 21, as shown in FIG. 4 b.
• the mold wafer 21 In order to be able to completely mold the structures of the mold wafer 21, it is generally necessary to carry out this bonding process in a vacuum
• the composite of the form wafer 21 and top cap wafer 2 is heated in an oven at 600-800 0 C
• the top cap wafer 2 starts to melt and the pressure difference between the vacuum in the groove 23, 24 of the molded wafer 21 and the consecutive higher ambient pressure in the furnace in the trenches 23, 24 of the molding wafer 21 is pressed until the trenches 23, 24 of the forming wafer 21 are completely filled with Borsihkatglas of the top lid wafer 2.
• the structures of the forming wafer 21 are completely on the top lid wafer. 2 Shaped Due to the glass flow, the side of the top cover wafer 2 facing away from the mold wafer 21 is no longer flat after cooling (FIG.
• the bottom lid wafer 3 is made flush on both sides or with a depression 16 on the side facing the carrier wafer
• the cover wafers 2, 3, which have an optical function have antireflection coatings 10 vapor-deposited from a layer system of magnesium fluoride and titanium oxide onto the surfaces parallel to the carrier wafer plane after the bonding process.
• These antireflection coatings 10 then have to be removed again from the contact regions 7 (FIG. 4e), since the antireflection coatings 10 were able to disturb the bonding process. The removal takes place by means of a polish, which attacks only the contact regions 7, but not the antireflection coatings 10 in the depressions 4, 16
• the lid wafers 2, 3 are finally bonded to the carrier wafer 1

Landscapes

• Engineering & Computer Science (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Computer Hardware Design (AREA)
• Manufacturing & Machinery (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Optics & Photonics (AREA)
• Micromachines (AREA)
• Mechanical Light Control Or Optical Switches (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (2)

Family

ID=39471629

Family Applications (1)

Country Status (7)

Cited By (4)

Families Citing this family (27)

Citations (5)

Family Cites Families (25)

• 2007
  • 2007-01-18 DE DE102007002725A patent/DE102007002725A1/de not_active Ceased
• 2008
  • 2008-01-17 WO PCT/EP2008/000321 patent/WO2008087022A1/de not_active Ceased
  • 2008-01-17 CA CA002675501A patent/CA2675501A1/en not_active Abandoned
  • 2008-01-17 KR KR1020097015082A patent/KR20090105933A/ko not_active Withdrawn
  • 2008-01-17 JP JP2009545870A patent/JP2010517064A/ja active Pending
  • 2008-01-17 US US12/448,911 patent/US8201452B2/en active Active
  • 2008-01-17 EP EP08707087.6A patent/EP2102096B1/de active Active

Patent Citations (5)

Also Published As

Similar Documents

Legal Events