Method of manufacturing electronic devices and corresponding electronic device

A first electronic component, such as a sensor having opposed first and second surfaces and a first thickness, is arranged on a support member with the second surface facing towards the support member. A second electronic component, such as an integrated circuit mounted on a substrate and having a second thickness less than the first thickness, is arranged on the support member with a substrate surface opposed the second electronic component facing towards the support member. A package molding material is molded onto the support member to encapsulate the second electronic component while leaving exposed the first surface of the first electronic component. The support member is then removed to expose the second surface of the first electronic component and the substrate surface of the substrate.

PRIORITY CLAIM

This application claims the priority benefit of Italian Application for Patent No. 102019000004835, filed on Apr. 1, 2019, the content of which is hereby incorporated by reference in its entirety to the maximum extent allowable by law.

TECHNICAL FIELD

The description relates to electronic devices.

One or more embodiments may be applied to sensors such as those of a Micro Electro-Mechanical Systems (MEMS) type.

BACKGROUND

Electronic devices including a Micro Electro-Mechanical Systems (MEMS) sensor and an associated “companion” chip such as an Application-Specific Integrated Circuit (ASIC) are now common in the art with the MEMS component mounted onto the companion integrated circuit (IC) chip or arranged on a same substrate as the companion IC chip.

Such devices may be packaged in a full-mold package having a thickness defined by the substrate and the mold chase.

Reducing the total device package thickness is a desirable goal which may be pursued by reducing the substrate thickness and/or reducing the chase thickness by improving process tolerances.

Another option in that direction may involve moving to a Chip Scale Package (CSP) process. It is noted that a CSP approach may not be applicable to MEMS and other sensor structures due to specific features of the associated Front End (FE) processes.

Exposing the “top” side of the semiconductor (silicon) substrate has also been proposed, primarily with the purpose of opening sensing ports in pressure sensors or optical devices, for instance. Exposing the “bottom” side of the substrate has also been proposed in order to improve thermal dissipation from the package.

It is noted that a limiting factor of such approaches is related to the use of a substrate, frame and/or mold compound surrounding (embedding, for instance) the device in its entirety.

There is a need in the art to provide a solution which overcomes the disadvantages outlined in the foregoing.

SUMMARY

One or more embodiments involve arranging side-by-side on a support surface (such as a tape, for instance) a sensor component (a MEMS component, for instance) and a companion chip (an ASIC, for instance) mounted on an associated substrate. After providing electric coupling between the sensor component and the companion chip, a packaging compound is overmolded on the assembly. The support tape is removed so that the resulting package exhibits a final thickness essentially corresponding to the (sole) thickness of the sensor component.

DETAILED DESCRIPTION

One or more embodiments as exemplified herein facilitate providing a full-mold package for an electronic device suited to be produced by resorting to standard and generally available technologies while pursuing a reduction of the total thickness of the resulting device.

One or more embodiments may be applied, for instance, to an electronics device10comprising:at least one first electronic component12such as a sensor (a MEMS sensor being exemplary of such an component), andat least one second electronic component14such as associated “companion” semiconductor integrated circuit chip or die (an ASIC being exemplary of such a semiconductor IC chip or die) mounted on a respective substrate16.

The designation “respective” highlights the fact that, in one or more embodiments as exemplified herein, the substrate16(which may be regarded as akin to a printed circuit board or PCB) is configured to support (only) the semiconductor chip14and not the sensor component12, so that the thickness of the substrate16does not add to the thickness of the sensor12.

As exemplified herein, the first component12will exhibit a front or “top” surface12aand a rear or “bottom” surface12bwith a thickness of the component12identified by the distance between the surfaces12a,12b.

As discussed previously, there is a need to reduce the total thickness of the device10by letting such a thickness be essentially determined by the thickness of the component12(a sensor such as a MEMS, for instance), possibly with both surfaces or sides of the component12(namely the front surface12aand the back surface12b) exposed at the package surface.

In one or more embodiments as portrayed in a first exemplary sequence of processing steps inFIGS.1A to1E, a (sacrificial) carrier20is provided (FIG.1A) onto which the component12(e.g. a sensor) and a companion component14(e.g. a semiconductor chip) are arranged side-by-side with the component14mounted on the substrate16. This may be via bumps18, as conventional in the art.

FIGS.1B to1Dare exemplary of processing steps in a manufacturing process which can be performed on a plurality of similar structures or assemblies arranged on a tape-like carrier20, with these structures eventually separated in a “singulation” step as exemplified inFIG.1Dto provide individual devices10(FIG.1E).

In one or more embodiments, the carrier20may include a tape (a polycarbonate tape, for instance) as conventional in manufacturing processes of integrated circuits (ICs).

Once the components12and14(wherein the component14is mounted on the substrate16) are arranged side-by-side on the carrier20, with electrical coupling22provided therebetween as desired (again by conventional solutions, such as wire bonding, for instance) a package molding compound24can be molded onto the previously formed assembly as exemplified inFIG.1C, that is by leaving exposed the “cap”, namely the front surface12aof the component12.

An Epoxy Molding Compound (EMC) may be exemplary of the package molding compound24.

FIG.1Dis exemplary of a singulation processing step (performed, in conventional manner, via a singulation tool indicated S) followed by removal of the carrier20(FIG.1E) leading to both the front side or surface12aand the rear or back side12bof the component12being exposed at the surface of the molding material24.

As a result the package thickness of the device10is determined by (that is, essentially the same as) the thickness of the component12alone (that is the thickness between the surfaces12a,12b).

Also, while the opposed surfaces12a,12bof the component12are exposed at the package surface, the material of the component14(a semiconductor such as silicon, for instance) is embedded and thus “floating” within the package molding compound24.

Those of skill in the art will easily appreciate that the sequence of processing steps ofFIGS.1A to1Eis merely exemplary and non-mandatory: for instance, singulation, here exemplified before removal of the carrier20, may take place after or simultaneously with removal of the carrier20.

InFIGS.2A to2Eparts, components or processing steps like parts, components or processing steps already discussed in connection withFIGS.1A to1Eare indicated with like reference symbols. A corresponding detailed description will not be repeated for brevity.

In embodiments as exemplified inFIGS.2A to2Eelectrical coupling of the component (semiconductor chip)14to the substrate16is achieved via wire-bonding (again indicated22) in the place of bumps such as bumps18inFIGS.1B to1E.

Here again, the package thickness of the device10is essentially determined by the thickness of the component12alone (that is the thickness between the surfaces12a,12b), with the possible “height” of the wire bond loops22having no practical impact on the total thickness of the device10even taking into account the thickness of the component14and the substrate (which may be reasonably expected to be thinner than the component12).

Here again, while the opposed surfaces12a,12bof the component12are exposed at the package surface, the material of the component14(a semiconductor such as silicon, for instance) is embedded and thus “floating” within the package molding compound24.

FIGS.3A and3Bcan be regarded as essentially corresponding toFIGS.1D and1Ewith parts, components or processing steps already discussed in connection withFIGS.1A to1Eindicated with like reference symbols. A corresponding detailed description will not be repeated for brevity.

FIGS.3A and3Bare exemplary of the possibility (which may apply both to embodiments as exemplified inFIGS.1A to1Eand to embodiments as exemplified inFIGS.2A to2E) of providing electromagnetic shielding material26onto the top or front surface of the component10(including the front or top surface12aof the component12).

Such an approach may be advantageous in case the component12(a sensor component, for instance) is sensitive to electromagnetic signal.

The shielding material26may comprise (in a manner known to those of skill in the art) electrically-conductive material such as a metal which can be applied onto the component10after device singulation and possible dedicated substrate design.

FIGS.4A and4Bcan be regarded again as essentially corresponding toFIGS.1D and1Ewith parts, components or processing steps already discussed in connection withFIGS.1A to1Eindicated with like reference symbols. A corresponding detailed description will not be repeated for brevity.

FIGS.4A and4Bare exemplary of the possibility (which may apply both to embodiments as exemplified inFIGS.1A to1Eand to embodiments as exemplified inFIGS.2A to2E) of providing a (very) thin sensor—a differential pressure sensor, for instance—with pressure ports120provided at the exposed surfaces (for instance both the front surface12aand the back surface12b) of the sensor component12.

Also those of skill in the art will appreciated that the stepped outline of the sides of the device inFIGS.4A and4Bis indicative of the possibility, in one or more embodiments, of providing shielding26as exemplified inFIGS.3A and3Balso in arrangements as exemplified inFIGS.4A and4B.

One or more embodiments thus make it possible to reduce the thickness of the device10by letting it be essentially given by the thickness of the first component12(a MEMS, for instance) without any contribution to the device thickness given by the substrate16for the companion component14and/or by the mold chase thickness.

In one or more embodiments as exemplified herein the (total) thickness of the molded package (seeFIGS.1E,2E,3B and4B, for instance) is determined by the thickness of a single component (here, the component12) which, contrary to the component14, has no associated substrate by avoiding a combination with the substrate and/or mold material thickness.

Also, one or more embodiments lend themselves (in the case of a small routing specifications and/or low signal count, for instance) to implementations where the substrate (16in the figures) is provided via a copper frame.

Also, certain embodiments (this may be the case of non-capped devices) may facilitate using a component14provided with a “dummy” die/interposer mounted on top. This may be advantageous in cases where the exposed front and/or back sides of the component may facilitate (via such a dummy die for instance) a thermal dissipation function and/or a thermal sensing function.

In one or more embodiments, electromagnetic interference (EMI) shielding can be enhanced by resorting to a shielding (metalized, for instance) backside and/or to conductive dummy dies at one or both of the opposed surfaces.

A method as exemplified herein may comprise:providing a (planar, for instance) support member (for instance,20),arranging on the support member:a) at least one first electronic component (for instance,12) having opposed first (for instance,12a) and second (for instance,12b) surfaces, the at least one first electronic component arranged on the support member with the second surface towards the support member, wherein the at least one first electronic component has a thickness between the opposed first and second surfaces (for instance, between12aand12b),b) at least one second electronic component (for instance,14) mounted on a substrate (for instance,16), the at least one second electronic component arranged on the support member with the substrate having a substrate surface (facing downwards, in the figures) opposed the at least one second electronic component and facing towards the support member, wherein the substrate and the at least one second electronic component mounted thereon have a joint (that is, cumulative) thickness which is less than the thickness of the at least one first electronic component (see, for instanceFIGS.1Bthru1E,FIGS.2Bthru2E,3A and3B,4A and4B),molding package molding material (for instance,24) onto the support member having arranged thereon the at least one first electronic component and the at least one second electronic component mounted on the substrate, wherein the package molding material encapsulates the at least one second electronic component leaving exposed (at the surface of the molding material) the first surface of the at least one first electronic component (see, for instance,FIGS.1C,2C,3A and4A), andseparating (removing, for instance) the support member to expose the second surface of the at least one first electronic component and the substrate surface of the substrate opposed the at least one second electronic component (see, for instance,FIGS.1E,2E,3B and4B).

A method as exemplified herein may comprise:a) providing electrically-conductive formations (for instance,18or22) between:the at least one second electronic component and the substrate (see, for instance, the bumps18inFIGS.1B to1Eor the wires22on the right side of the component14inFIGS.2B to2E), and/orthe at least one first electronic component and the substrate (see, for instance, the wires22on the right side of the component12inFIGS.1B to1E and2B to2E), and/orthe at least one first electronic component and the at least one second electronic component (see, for instance, the wires22between the components12and14inFIGS.2B to2E),b) molding the package molding material onto the support member having arranged thereon the at least one first electronic component and the at least one second electronic component mounted on the substrate, wherein the package molding material encapsulates said electrically-conductive formations.

A method as exemplified herein may comprise providing electromagnetic shielding material (for instance,26) over at least one (for instance,12a) of the first and second opposed surfaces of the at least one first electronic component. As discussed a “dummy” shield may be provided on either of both of these surfaces.

In a method as exemplified herein the at least one first electronic component may comprise a pressure sensor with at least one of the opposed first and second surfaces provided with pressure ports (for instance,120).

In a method as exemplified herein, the support member may comprises a tape.

In a method as exemplified herein:the at least one first electronic component may comprise a sensor, optionally a MEMS, and/orthe at least one second electronic component may comprise a semiconductor integrated circuit chip, optionally an ASIC.

A method as exemplified herein may comprise:arranging on the support member a sequence of assemblies, wherein each assembly may comprise:a) at least one first electronic component having opposed first and second surfaces, the at least one first electronic component arranged on the support member with the second surface towards the support member, wherein the at least one first electronic component has a thickness between the opposed first and second surfaces,b) at least one second electronic component mounted on a substrate, the at least one second electronic component arranged on the support member with the substrate having a substrate surface opposed the at least one second electronic component and facing towards the support member, wherein the substrate and the at least one second electronic component mounted thereon have a joint thickness with is less than the thickness of the at least one first electronic component,molding onto the support member having arranged thereon said sequence of assemblies, package molding material to encapsulate the at least one second electronic component in the assemblies in said sequence of assemblies leaving exposed the first surface of the at least one electronic component in the assemblies in said sequence of assemblies,separating the support member to expose the second surface of the at least one first electronic component and the substrate surface of the substrate opposed the at least one second electronic component in the assemblies in said sequence of assemblies, andsingulating (for instance, S) said sequence of assemblies into individual devices including at least one said first electronic component and least one said second electronic component coupled therewith.

A device (for instance,10) as exemplified herein, may comprise:at least one first electronic component having opposed first and second surfaces, the at least one first electronic component arranged on the support member with the second surface towards the support member, wherein the at least one first electronic component has a thickness between the opposed first and second surfaces,at least one second electronic component mounted on a substrate, the at least one second electronic component arranged on the support member with the substrate having a substrate surface opposed the at least one second electronic component and facing towards the support member, wherein the substrate and the at least one second electronic component mounted thereon have a joint thickness with is less than the thickness of the at least one first electronic component, andpackage molding material encapsulating the at least one second electronic component leaving exposed the opposed first and second surfaces of the at least one electronic component and the substrate surface of the substrate opposed the at least one second electronic component.

A device as exemplified herein may comprise electrically-conductive formations between:the at least one second electronic component and the substrate, and/orthe at least one first electronic component and the substrate, and/orthe at least one first electronic component and the at least one second electronic component,

wherein said package molding material may encapsulate said electrically-conductive formations.

A device as exemplified herein may comprise electromagnetic shielding material over at least one of the first and second opposed surfaces of the at least one first electronic component.

In a device as exemplified herein the at least one first electronic component may comprise a pressure sensor, with at least one of the opposed first and second surfaces provided with pressure ports.

In a device as exemplified herein:the at least one first electronic component (12) may comprise a sensor, optionally a MEMS, and/orthe at least one second electronic component (14) may comprise a semiconductor chip, optionally an ASIC.

The claims are an integral part of the technical disclosure of embodiments as provided herein.

The extent of protection is determined by the annexed claims.