SIMPLE TO PRODUCE ELECTRIC COMPONENT AND METHOD FOR PRODUCING AN ELECTRIC COMPONENT

20170272855 · 2017-09-21

    Inventors

    Cpc classification

    International classification

    Abstract

    The invention relates to a simple to produce electric component for chips with sensitive component structures. Said component comprises a connection structure and a switching structure on the underside of the chip and a support substrate with at least one polymer layer.

    Claims

    1. An electric component (B) comprising: a support substrate (TS) comprising at least one polymer layer (TSO), a first chip (CH1) comprising a connection structure (VBS) on its underside and comprising a metallic switching structure (VSS) on its underside, wherein the first chip (CH1) is arranged on the support substrate (TS), the connection structure (VBS) rests on the polymer layer (TSO) or protrudes into the polymer layer (TSO) without penetrating through it, and the switching structure (VSS) penetrates through the polymer layer (TSO).

    2. The component according to the preceding claim, wherein the first chip (CH1) is selected from: an MEMS chip, an NEMS chip, an IC chip, an opto-electronic chip, an actuator chip, a chip comprising only passive switching elements.

    3. The component according to any of the preceding claims, wherein the support substrate (TS) furthermore comprises a layer (TSU) selected from: an SESUB, a printed circuit board, an LTCC substrate, an HTCC substrate, an organic support foil, an inorganic support foil, a metal foil, a monocrystalline substrate, a polycrystalline substrate, a semiconductive substrate, a ceramic substrate, a glass substrate.

    4. The component according to any of the preceding claims, furthermore comprising a gap between the first chip (CH1) and the support substrate (TS), wherein sensitive structures (BES) are arranged on the underside of the first chip (CH1) without touching the support substrate (TS).

    5. The component according to the preceding claim, wherein the gap is delimited laterally by the connection structure (VBS) formed as frame (R) on the underside of the chip and wherein the chip (CH1), the frame (R), and the support substrate (TS) enclose a cavity (H).

    6. The component according to any of the preceding claims, wherein the connection structure (VBS) comprises as main component a polymer, Cu, Al, Ag, or Au, and the switching structure (VSS) comprises as main component Cu, Al, Ag, or Au.

    7. The component according to any of the preceding claims, wherein the switching structure (VSS) comprises a bump connection or metallic pillars or a through-connection through the chip (CH1) and/or the support substrate (TS)

    8. The component according to any of the preceding claims, wherein the connection structure (VBS) comprises supports having a round or rectangular cross section or supporting frames (R).

    9. The component according to any of the preceding claims, furthermore comprising a second chip (CH2), which is arranged above or on the first chip (CH1) or next to the first chip (CH1) on the support substrate (TS).

    10. The component according to any of the preceding claims, furthermore comprising an encapsulation with a laminate, a mold mass (VM), a mass applied by a printing method, or a foil (F) above the first chip (CH1), and/or a filler material (UF) arranged directly on a region of the support substrate (TS) and filling a gap between a chip material and the support substrate (TS).

    11. The component according to any of the preceding claims, furthermore comprising a cover layer made of metal over the first chip (CH1).

    12. The component according to any of the preceding claims, in which the first chip (CH1) or an additional chip (CH2, CH3) is a sensor chip and arranged underneath a covering (D), wherein the sensor chip is connected to the environment of the component (B) via a hole (L) in the covering (D).

    13. The component according to the preceding claim, wherein the component is a microphone, the sensor chip comprises electro-acoustic transducer structures, and a rear volume (RV) is formed below the covering (D).

    14. The component according to any of the preceding claims, comprising at least one additional chip (CH2, CH3), wherein the additional chip (CH2, CH3) is arranged on the top side of the support substrate (TS) and the connecting path on the support substrate (TS) between the first chip (CH1) and the additional chip (CH2, CH3) is so long that the support substrate (TS) can be bent between the chips (CH1, CH2, CH3).

    15. The component according to any of the preceding claims, furthermore comprising, on the top side of the support substrate (TS), exposed conductor paths (SL) provided to be connected to and interconnected with an external circuit environment via a plug connection.

    16. A method for producing an electric component (B), comprising the steps: Providing a first chip (CH1), Forming a metallic connection structure (VBS) and a metallic switching structure (VSS) on the underside of the first chip (CH1), wherein the two structures (VBS, VSS) have different heights, Providing a support substrate (TS) comprising a soft polymer layer (TSO), Connecting the first chip (CH1) to the support substrate (TS), wherein the switching structure (VSS) penetrates through the polymer layer (TSO) and the connection structure (VBS) touches the polymer layer (TSO) without penetrating through it.

    17. The method according to the preceding claim, wherein the polymer layer (TSO) is cured by exposure to light or by heating after placing the first chip (CH1).

    18. The method according to the preceding claim, wherein the support substrate (TS) comprises, underneath the polymer layer (TSO), a layer that is transparent in a suitable optical wavelength range and wherein the curing of the polymer layer (TSO) takes place by exposing it to light in this wavelength range.

    19. The method according to any of the preceding claims, wherein an additional chip (CH2) or a plurality of additional chips (CH2, CH3) are additionally arranged next to or on the first chip (CH1).

    20. The method according to any of the preceding claims, wherein a filler material (UF) is arranged in the regions between a chip material (CH1, CH2, CH3) and the support substrate (TS).

    21. The method according to any of the preceding claims, wherein a mold mass (VM) and/or a foil (F) is applied over the first chip (CH1).

    22. The method according to any of the preceding claims, wherein a metallic cover layer is applied over the first chip (CH1).

    23. The method according to any of the preceding claims, wherein the support substrate (TS) comprises an additional layer (TSU) underneath the polymer layer (TSO) and wherein the additional layer (TSU) is removed completely or selectively in the regions of the switching structure (VSS) after curing of the polymer layer (TSO) and wherein the switching structure (VSS) is exposed.

    24. The method according to the preceding claim, wherein the exposing of the switching structure (VSS) takes place using a laser.

    25. The method according to any of the two preceding claims, wherein the switching structure (VSS) comprises contacts (KP), the contacts (KP) are contacted by forming conductor structures (SL) on the underside of the support substrate (TS) after the exposing.

    26. The method according to any of the preceding claims, wherein the component is produced together with a plurality of other components in multiple applications and separated from the other components.

    27. The method according to any of the preceding claims, wherein on the top side of the component, a layer combination comprising layers containing Cu, Ni, and black nickel is applied and subsequently labeled by selectively removing the Ni-containing material.

    28. The method according to any of the preceding claims, wherein electrically conductive structures (SL) are formed on the surface of the chip (CH1) and/or on the surface of the support substrate (TS) by depositing a metal or an alloy or by jetting metal-containing nanoparticles.

    Description

    BRIEF DESCRIPTION OF THE DRAWINGS

    [0061] FIG. 1: a bottom support substrate layer TSU serving as base for the polymer layer,

    [0062] FIG. 2: a support substrate with a top support substrate layer TSO,

    [0063] FIG. 3: a first chip CH1 with component structures BES on its underside,

    [0064] FIG. 4: the first chip, on the underside of which a switching

    [0065] FIG. 5: a version of the chip, on the underside of which a connection structure VES is furthermore arranged,

    [0066] FIG. 6: the arrangement of the first chip CH1 on the support substrate TS,

    [0067] FIG. 7: the arrangement of a second chip CH2 on the support substrate TS,

    [0068] FIG. 8: a portion of the support substrate, on which the first chip CH1 and the second chip CH2 are arranged next to each other,

    [0069] FIG. 9: a filler material UF in a gap between the second chip CH2 and the support substrate,

    [0070] FIG. 10: a support substrate, in the bottom layer TSU of which holes L are structured,

    [0071] FIG. 11: metalizations M on the underside of the support substrate, which metalizations realize contact pads KP and signal paths between different electrical contacts of the chips,

    [0072] FIG. 12: an embodiment of the support substrate, which, after the curing of the polymer layer, no longer comprises any additional layers except for the polymer layer,

    [0073] FIG. 13: the direct arrangement of the second chip CH2 on the polymer layer without additional filler material,

    [0074] FIG. 14: a support substrate, which is not reinforced by a filler material underneath the second chip,

    [0075] FIG. 15: a foil F, which is arranged over the chips on the top side of the support substrate,

    [0076] FIG. 16: a top view of a component, illustrating the effect of the frame-shaped connection structure as barrier against a filler material,

    [0077] FIG. 17: a component with signal lines and contact pads on the top side of the support substrate for forming a plug connection,

    [0078] FIG. 18: a component with a casting compound VM,

    [0079] FIG. 19: a component designed as a microphone with a rear volume underneath a cover,

    [0080] FIG. 20: a component designed as a microphone with a rear volume in a recess underneath the first chip,

    [0081] FIG. 21: an embodiment of the component as a microphone, in which a large portion of the rear volume is arranged in a recess next to the electro-acoustic transducer chip.

    [0082] FIG. 6 shows the essential geometric dimensions or structure heights of the connection structure VBS and the switching structure VSS relative to the thickness of the polymer-containing top layer of the support substrate TSO. The connection structure VBS and the switching structure VSS are arranged on the underside of the first chip CH1. The height of the switching structure VSS exceeds the height of the connection structure VBS. The connection structure VBS substantially serves to maintain a distance between the underside of the first chip CH1 and the top side of the support substrate TS. In doing so, the connection structure VBS touches the top layer TSO of the support substrate TS, which top layer substantially consists of a polymer material. It is possible that the connection structure VBS substantially sits on the top side of the top layer TSO or is possibly slightly pressed into the top layer TSO.

    [0083] As a result of its larger height, the switching structure VSS penetrates through the polymer-containing top layer TSO of the support substrate TS. If an electrical contact to elements of the switching structure VSS is to take place at a later time, only the bottom layer of the support substrate TSU must be penetrated. In this case, the top layer TSO can substantially remain and ensure a mechanical stability.

    [0084] FIGS. 1 to 5 show essential steps for producing such a component:

    [0085] FIG. 1 shows the base layer of the support substrate, namely a bottom layer TSU of the support substrate.

    [0086] A polymer-containing top layer TSO is applied onto it (FIG. 2). The top layer is in this case so soft that the switching structure VSS can later easily penetrate through it. It is in particular possible that the top layer TSO is liquid.

    [0087] FIG. 3 shows a first chip CH1, which carries sensitive component structures BES on its underside, such as SAW structures, BAW structures, or membranes, or backplates. The component structures are characterized in that they are arranged on the underside of the first chip CH1 so as to freely vibrate in order to ensure a proper function.

    [0088] FIG. 4 shows how a switching structure VSS may be arranged on the underside of the first chip CH1 in order to interconnect, for example, the component structures with an external circuit environment or with additional switching elements of the component.

    [0089] FIG. 5 additionally shows the connection structure VBS on the underside of the first chip. In order to be able to maintain a sufficient distance between the component structures BES and the support substrate TS provided for them, the connection structure VBS preferably has a larger installation height than the component structures BES.

    [0090] In this way, after connecting the first chip CH1 to its structures on its underside and to the support substrate TS, the component shown in FIG. 6 is obtained, in which the component structures have a sufficient distance to the support substrate TS. If the connection structure VBS is self-contained, a closed cavity is obtained in particular, in which the component structures are arranged.

    [0091] Furthermore, FIG. 7 shows a portion of the support substrate TS, on which a second chip CH2 is arranged. The second chip does not need to comprise any sensitive component structures on its surface. Therefore, a direct contact of its underside to the support substrate TS is harmless. Connection structures between the second chip CH2 and the support substrate TS are possible but not necessary.

    [0092] FIG. 8 now shows a component B, in which a first chip CH1 with mechanically sensitive component structures on its underside is arranged on the support substrate together with a less sensitive second chip CH2. Both chips comprise electrical contact structures on their undersides, which contact structures extend through the polymer-containing top layer of the support substrate TS.

    [0093] FIG. 9 shows an embodiment, in which the second chip CH2 is not in direct contact with the support substrate. If a free space between the second chip CH2 and the support substrate TS is undesired, the volume underneath the second chip CH2 can be filled with a filler material, such as an underfiller UF.

    [0094] Since the connection structure VBS of the first chip CH1 may be designed as an annularly closed frame R, the sensitive component structures on the underside of the first chip CH1 are also not compromised by the application of the underfiller UF. Rather, the filler material UF can improve a hermetical sealing of the cavity underneath the first chip CH1.

    [0095] FIG. 10 shows a substantial advantage of the present design compared to conventional components for the case that the switching structures VSS are to be contacted electrically. The top layer of the support substrate has preferably been cured in the meantime and can provide a sufficient mechanical stability. It is then only necessary to penetrate through the layers TSU located underneath and to thereby expose the switching structures VSS in order to carry out an interconnection of the switching structures by forming signal lines. In this way, holes L may be drilled, for example using a laser, into the layer TSU of the support substrate TS, said layer being arranged underneath the polymer layer.

    [0096] FIG. 11 shows the metalizations M arranged via usual lithography processes on the underside of the support substrate and interconnecting the electrical contacts of the chips with one another or the contacts of the chips and external contact pads KP.

    [0097] FIG. 12 shows an embodiment, in which individual holes L are not selectively drilled on the positions of the switching structure VSS, but the bottom layer TSU of the support substrate TS is completely removed before the metalization M is applied on the underside to form signal paths.

    [0098] FIGS. 13 and 14 show the respective electrical connections on the underside of the support substrate, wherein no filler material is arranged between the support substrate and the second chip CH2. Depending on the thickness and stability of the polymer layer, the latter already provides a sufficient mechanical stability (FIG. 14).

    [0099] FIG. 15 shows another possibility of covering the top side of the component by a foil F. Depending on how far the chips are spaced apart from each other on the top side of the support substrate, it is possible to connect the foil F to the top side of the support substrate or to enclose a cavity between the chips underneath the foil. If the foil touches the top side of the support substrate, the foil can be interconnected with an electric potential, e.g. via through-connections through the support substrate. It is furthermore possible to separate a support substrate produced accordingly in multiple applications in order to obtain a plurality of different components, wherein the sealing of the foil is not undermined by the separation. If the foil, together with the support substrate and the lateral surfaces of the chips, forms cavities, they may be formed as rear volumes for microphones.

    [0100] FIG. 16 shows the protective effect of a connection structure VBS formed as a frame, which connection structure effectively prevents a flooding of the cavity H underneath the first chip CH1 by the filler material UF. The component structures BES are thus safely accommodated in the cavity H.

    [0101] In addition to the first chip CH1, an additional chip CH2 and a third chip CH3 are arranged on the top side of the support substrate.

    [0102] FIG. 17 shows the possibility of forming signal lines SL by means of metalizations on the surface of the support substrate.

    [0103] The signal lines may in this case extend from the contacts of one of the chips to an edge of the component and end in a contact pad KP. A plug connection to an external switching environment is thus easily made possible.

    [0104] Bending lines KN may be selected such that chips or other switching elements still have sufficient room on the top side of the support substrate after the support substrate has been bent at the bending edge KN. After the bending, the support substrate may be cast with its components on the surface by means of a casting material, such as a polymer or a synthetic resin.

    [0105] Such a casting compound is shown in FIG. 18. In doing so, the casting compound covers the entire top side of the component.

    [0106] FIG. 19 shows an embodiment of the component as a microphone. The first chip CH1 carries a membrane MB and a backplate RP as component structures. The top side of the support substrate is covered by a cover D. In the cover D, holes are structured as sound entry openings. The cover D furthermore comprises a rear volume RV next to the first chip CH1. In order to avoid an acoustic short circuit, an acoustic seal AD is formed between the sound entry and the rear volume RV. The connection structure is in this case not completely closed so that a gas exchange between the volume behind the membrane MB of the first chip CH1 and the rear volume RV is possible.

    [0107] FIG. 20 shows the possibility of providing the rear volume behind the membrane by means of a recess in the support substrate or its top layer TSO.

    [0108] The thicker the top layer of the support TSO is, the larger is the rear volume RV. The switching structures are in this case long enough to penetrate completely through the top layer TSO.

    [0109] FIG. 21 shows another embodiment of the component as a microphone, in which a portion of the rear volume is formed by a recess AU in the support substrate next to the first chip. Additional holes L through the support substrate constitute a sound entry opening. In this exemplary embodiment, the connection structures are annularly closed in order to avoid an acoustic short circuit.

    [0110] Neither the component nor the method for producing a component are limited to the embodiments shown or described.

    LIST OF REFERENCE SYMBOLS

    [0111] AU: Recess

    [0112] B: Component

    [0113] BES: Component structures

    [0114] CH1: First chip

    [0115] CH2: Second chip

    [0116] CH3: Third chip

    [0117] D: Cover

    [0118] F: Foil

    [0119] H: Cavity

    [0120] KN: Bending line

    [0121] KP: Contact pad

    [0122] L: Hole

    [0123] M: Metalization

    [0124] MB: Membrane

    [0125] R: Frame

    [0126] RP: Backplate

    [0127] RV: Rear volume

    [0128] SL: Signal conductor

    [0129] TS: Support substrate

    [0130] TSO: Top layer of the support substrate

    [0131] TSU: Layer underneath the top layer of the support substrate

    [0132] UF: Filler material or underfiller

    [0133] VBS: Connection structure

    [0134] VM: Casting compound

    [0135] VSS: Switching structure