CH619333A5 - Process for covering a flat component with a polymer - Google Patents
Process for covering a flat component with a polymer Download PDFInfo
- Publication number
- CH619333A5 CH619333A5 CH1332277A CH1332277A CH619333A5 CH 619333 A5 CH619333 A5 CH 619333A5 CH 1332277 A CH1332277 A CH 1332277A CH 1332277 A CH1332277 A CH 1332277A CH 619333 A5 CH619333 A5 CH 619333A5
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- polymer
- substrate
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- 229920000642 polymer Polymers 0.000 title claims abstract description 54
- 238000000034 method Methods 0.000 title claims abstract description 30
- 239000000758 substrate Substances 0.000 claims abstract description 46
- 239000004020 conductor Substances 0.000 claims abstract description 23
- 239000007788 liquid Substances 0.000 claims abstract description 23
- 239000004033 plastic Substances 0.000 claims abstract description 19
- 238000005530 etching Methods 0.000 claims abstract description 8
- 238000009434 installation Methods 0.000 claims abstract description 3
- 239000013078 crystal Substances 0.000 claims description 6
- 239000004065 semiconductor Substances 0.000 claims description 5
- 239000000919 ceramic Substances 0.000 claims description 4
- 239000003822 epoxy resin Substances 0.000 claims description 4
- 239000011521 glass Substances 0.000 claims description 4
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 4
- 229910052737 gold Inorganic materials 0.000 claims description 4
- 239000010931 gold Substances 0.000 claims description 4
- 229920000647 polyepoxide Polymers 0.000 claims description 4
- 229920002050 silicone resin Polymers 0.000 claims description 4
- 229910000679 solder Inorganic materials 0.000 claims description 4
- 239000002985 plastic film Substances 0.000 claims description 3
- 229920006255 plastic film Polymers 0.000 claims description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 2
- 229910052782 aluminium Inorganic materials 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 claims description 2
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 239000010949 copper Substances 0.000 claims description 2
- 239000011810 insulating material Substances 0.000 claims description 2
- 238000003475 lamination Methods 0.000 claims description 2
- 239000000463 material Substances 0.000 claims description 2
- 239000000853 adhesive Substances 0.000 abstract description 3
- 230000001070 adhesive effect Effects 0.000 abstract description 3
- 239000004922 lacquer Substances 0.000 description 2
- 239000000654 additive Substances 0.000 description 1
- 238000010923 batch production Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000004382 potting Methods 0.000 description 1
- 238000005476 soldering Methods 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
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- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/50—Assembly of semiconductor devices using processes or apparatus not provided for in a single one of the subgroups H01L21/06 - H01L21/326, e.g. sealing of a cap to a base of a container
- H01L21/56—Encapsulations, e.g. encapsulation layers, coatings
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- H01L23/31—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection characterised by the arrangement or shape
- H01L23/3107—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection characterised by the arrangement or shape the device being completely enclosed
- H01L23/3121—Encapsulations, e.g. encapsulating layers, coatings, e.g. for protection characterised by the arrangement or shape the device being completely enclosed a substrate forming part of the encapsulation
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- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/22—Secondary treatment of printed circuits
- H05K3/28—Applying non-metallic protective coatings
- H05K3/284—Applying non-metallic protective coatings for encapsulating mounted components
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- H01L2224/48465—Connecting portions the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
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- Encapsulation Of And Coatings For Semiconductor Or Solid State Devices (AREA)
Abstract
A flat component (2) located on a substrate (1) provided with conductors (3) is enclosed by a border (6). The border (6) is formed by etching a photosensitive plastic layer which is applied to the substrate (1) and exposed to light according to the contours of the border (6). After the installation of the component (2) on the substrate (1), liquid polymer (8) is applied to the bordered region in an amount such that it covers the component (2) and extends as far as the outer edges (7) of the border (6). Then the polymer (8) is cured. As a consequence of the etching, the outer edges (7) of the border (6) have a large edge angle, so that the adhesive tension at the edges (7) is less than the surface tension and the polymer (8) cannot creep over the edges (7). A precise, unchangeable and also, in the case of an excess amount of the liquid polymer, reliable lateral border of the covering of the component can thereby be obtained with low outlay and by a series procedure. <IMAGE>
Description
**WARNUNG** Anfang DESC Feld konnte Ende CLMS uberlappen **.
PATENTANSPRÜCHE
1. Verfahren zur seitlich begrenzten Abdeckung eines auf einem mit Leiterbahnen versehenen Substrat befindlichen flachen Bauteils mit einem flüssigen, härtbaren Polymer, dadurch gekennzeichnet, dass eine das Bauteil umschliessende Umrandung, deren Aussenkontur der seitlichen Begrenzung der herzustellenden Abdeckung entspricht, durch Ätzen einer auf das Substrat aufgebrachten, photoempfindlichen, gemäss den Konturen der Umrandung belichteten Kunststoffschicht gebildet wird und dass nach dem Einbau des Bauteils das flüssige Polymer in einer solchen Menge auf den umrandeten Bereich gebracht wird, dass es das Bauteil bedeckt und sich bis zur äusseren Kante der Umrandung erstreckt, worauf das Polymer ausgehärtet wird.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass zum Aufbringen der Kunststoffschicht auf das Substrat eine photoempfindliche Kunststoffolie verwendet wird.
3. Auf einem Substrat befindliches, gemäss dem Verfahren nach Anspruch 1 abgedecktes Bauteil.
4. Anwendung des Verfahrens nach Anspruch 1 zur Abdekkung eines plättchenförmigen Halbleiterbauteils.
Die Erfindung bezieht sich auf ein Verfahren zur seitlich begrenzten Abdeckung eines auf einem mit Leiterbahnen versehenen Substrat befindlichen flachen Bauteils mit einem flüssigen, härtbaren Polymer.
Empfindliche Bauteile, die auf einem mit Leiterbahnen versehenen Substrat, z. B. einer Platte aus Keramik, Glas oder einem anderen Isolierstoff, montiert sind, müssen durch eine Abdeckung gegen mechanische Beschädigung und schädliche atmosphärische Einwirkungen geschützt werden. Dies ist insbesondere für flache Halbleiterkristalle oder integrierte Schaltungen der Fall, welche über sehr dünne Drähte, sogenannte Bonddrähte, mit den Leiterbahnen verbunden sind. Als Material für die Abdeckung wird hierbei ein auf das Bauteil gebrachter Tropfen eines flüssigen Polymers, z. B. eines Epoxidharzes oder eines Silikonharzes, verwendet, welches nach dem Aufbringen ausgehärtet wird.
Die im flüssigen Zustand des aufgebrachten Polymers eintretende Ausdehnung des Tropfens muss seitlich begrenzt werden, da das Polymer sonst in einen Bereich der Leiterbahnen fliesst, in welchem anschliessend, d. h. nach dem Aushärten des Polymers, Lötverbindungen herzustellen sind. Bei einem im Gebrauch stehenden Verfahren wird der Polymertropfen frei auf das abzudeckende Bauteil gebracht, wobei durch Wahl des Polymers bezüglich seiner Oberflächenspannung und Thixotropie sowie durch Abtupfen des Substrats längs der vorgesehenen Begrenzung der Abdeckung mit ganz geringen Mengen des Polymers versucht wird, dessen Ausfliessen zu verhindern.
Mit diesem Verfahren, das zudem eine aufwendige Handarbeit erfordert, kann jedoch die Form des ausgehärteten Tropfens nicht oder nur sehr schwach bzw. unter Inkaufnahme einer hohen Ausschussquote genau definiert werden. Vielmehr kann ein Kriechen des Polymers bis zu seiner Aushärtung nicht verhindert werden, insbesondere weil Leiterbahnen dessen Rand kreuzen.
Es ist auch schon ein Verfahren angewendet worden, bei welchem zur Begrenzung des flüssigen Polymertropfens das Substrat mit einer Aussparung oder einer erhöhten Umrandung versehen wird. Eine Aussparung kann aber im Substrat im allgemeinen nicht mit der erforderlichen Tiefe gebildet werden, so dass weiterhin die Gefahr besteht, dass das flüssige Polymer über den Rand der Aussparung ausfliesst. Das Aufbringen einer erhöhten Umrandung, d. h. eines Rahmens, der erforderlichen Höhe auf das Substrat ist mit erheblichem Zeit- und Kostenaufwand verbunden, da die Umrandungen einzeln hergestellt, auf dem Substrat sorgfältig plaziert und auf diesem befestigt, z. B.
angeklebt werden müssen.
Aufgabe der Erfindung ist, ein Verfahren der eingangs genannten Art zu schaffen, das eine exakte, unveränderliche und auch bei einer übermässig grossen Menge des aufgebrachten flüssigen Polymers sichere seitliche Begrenzung der Abdeckung mit geringem Aufwand und in Serien-Arbeitsweise erlaubt.
Erfindungsgemäss ist das Verfahren dadurch gekennzeichnet, dass eine das Bauteil umschliessende Umrandung, deren Aussenkontur der seitlichen Begrenzung der herzustellenden Abdeckung entspricht, durch Ätzen einer auf das Substrat aufgebrachten, photoempfindlichen, gemäss den Konturen der Umrandung belichteten Kunststoffschicht gebildet wird und dass nach dem Einbau des Bauteils das flüssige Polymer in einer solchen Menge auf den umrandeten Bereich gebracht wird, dass es das Bauteil bedeckt und sich bis zur äusseren Kante der Umrandung erstreckt, worauf das Polymer ausgehärtet wird.
Der Erfindung liegt die Erkenntnis zugrunde, dass unter dem Einfluss der Oberflächenspannung die seitliche Ausdeh nung eines Tropfens durch die abfallenden äusseren Ränder einer Unterlage für den Tropfen oder einer Umrandung begrenzt wird. Somit braucht eine zur seitlichen Begrenzung der Abdeckung eines Bauteils vorgesehene Umrandung bloss eine geringe Höhe zu haben, die wesentlich kleiner ist als die Höhe des das Bauteil abdeckenden Tropfens. Die Erfindung ermöglicht es demnach, als Umrandung eine dünne Kunststoffschicht vorzusehen, wobei die Umrandung auf sehr wirtschaftliche Art durch Ätzen einer photoempfindlichen Kunststoffschicht hergestellt wird.
Ausführungsbeispiele der Erfindung werden nachstehend anhand der Zeichnung erläutert. Es zeigen:
Fig. 1 einen schematischen Schnitt durch eine nach dem erfindungsgemässen Verfahren hergestellte Abdeckung eines Kristallplättchens oder des Plättchens einer integrierten Schaltung,
Fig. 2 einen schematischen Schnitt ähnlich Fig. 1 mit einer anderen Anordnung des Plättchens auf einem Substrat.
Gemäss Fig. 1 und 2 ist auf einem flachen Substrat 1, das aus einem Kunststoff, aus Keramik oder aus Glas bestehen kann, ein Plättchen 2 montiert, beispielsweise ein Kristallplättchen, ein Plättchen einer integrierten Schaltung oder ein anderes flaches Bauteil niedriger Höhe. Das Substrat list mit Leiterbah nen 3 versehen, die aus einer Kupferkaschierung des Substrats 1, aus einer Leitpaste oder aus Gold bestehen können.
Anschlusspunkte 4 des Plättchens 2 sind über dünne Drähte 5, sogenannte Bonddrähte aus Aluminium oder Gold, mit den Leiterbahnen 3 verbunden. Ausserhalb der Verbindungsstellen der Drähte 5 mit den Leiterbahnen 3 befindet sich eine gegenüber der Oberfläche des Substrats 1 bzw. der Leiterbah nen 3 erhöhte, aus Kunststoff bestehende Umrandung 6, die geschlossen ist und demnach das Plättchen 2 samt den Drähten 5 umschliesst. Die Kontur der Umrandung 6 kann beliebig, z. B.
kreisförmig oder rechteckig, sein. Der Querschnitt der Umrandung 6 ist angenähert rechteckig, wobei die äussere Kante 7 der Umrandung scharf ist Die Höhe der Umrandung beträgt beispielsweise 0,1 mm.
Das Innere der Umrandung 6 ist mit einem Polymerisat 8, d. h. mit einem ausgehärteten, ursprünglich flüssigem Polymer, z. B. einem Epoxidharz oder einem Silikonharz, abgedeckt oder vergossen. Gemäss den dargestellten Oberflächen 9 des Polymerisats deckt dieses das Plättchen 2 und die Drähte 5 vollkommen ab und erstreckt sich bis zur äusseren Kante 7 bzw.
den äusseren Kanten der Umrandung 6. Die Oberfläche 9 des abdeckenden Polymerisats 8 ist beim Beispiel der Fig. 2 weniger hoch über dem Substrats 1 als beim Beispiel der Fig. 1, weil
beim Beispiel der Fig. 2 das Plättchen 2 in einer Aussparung 10 des Substrats 1 montiert ist
Die Herstellung der dargestellten Abdeckungen erfolgt in der nachstehend angeführten Weise. Das mit den Leiterbahnen 3 versehene Substrat 1 wird auf seiner Oberfläche mit einer photoempfindlichen Kunststoffschicht versehen. Diese Kunststoffschicht kann beispielsweise durch Besprühen des Substrats 1 mit einem photoempfindlichen Lack aufgebracht werden. Da zur Erzielung einer Schichtdicke von etwa 0,1 mm hierbei das Aufsprühen des Lackes in mehereren Schritten erfolgen muss, ist es vorteilhafter, eine als Lötstoppfilm handelsübliche photoempfindliche Folie auf das Substrat 1 aufzubringen, beispielsweise durch Warmpressen.
Hierauf wird die aufgebrachte Kunststoffolie entsprechend den Konturen der gewünschten Umrandung 6 belichtet Die belichtete Kunststoffschicht wird anschliessend geätzt, so dass nur die belichtete Umrandung 6 auf dem Substrat 1 stehen bleibt. Eine hierbei auftretende, in den Fig. 1 und 2 angedeutete Unterätzung 11 ist nicht nur ohne Nachteil, sondern bewirkt in vorteilhafter Weise eine scharfe Kante 7.
Das Substrat 1 wird nun mit den erforderlichen Bauteilen, insbesondere dem Plättchen 2, bestückt. Hierauf wird auf das Plättchen 2 ein Tropfen des als Abdeck- bzw. Vergussmasse vorgesehene flüssigen Polymere gebracht, und zwar in einer solchen Menge, dass das Plättchen 2 samt der Drähte 5 vollkommen bedeckt ist. Das Polymer fliesst hierbei bis zur inneren Kante bzw. den inneren Kanten der Umrandung 6 und dann auf die Oberseite der Umrandung 6. Der Polymertropfen wird jedoch an der äusseren Kante 7 bzw. den äusseren Kanten der Umrandung 6 festgehalten, da zufolge des grossen Randwinkels an der Kante 7 die Haftspannung kleiner als die Oberflächenspannung ist Somit kann das Polymer nicht über die Kante 7 kriechen, auch wenn die Viskosität des Polymers bei einer anschliessenden, allenfalls unter mässiger Wärmeeinwirkung erfolgenden Aushärtung vorerst kleiner wird.
Es folgt also, dass sich das in den Fig. 1 und 2 dargestellte Polymerisat 8 unabhängig von seiner Höhe, d. h. unabhängig von der Grösse des Polymertropfens, nicht weiter als bis zur äusseren Kante 7 der Umrandung 6 erstrecken kann.
Das erfindungsgemässe Verfahren weist den Vorteil auf, dass es erlaubt, genau, schnell und kostengünstig die Abdekkung des Bautels seitlich zu begrenzen, so dass das Verfahren für die serienmässige Herstellung von Substraten mit Halbleiterbauteilen, sogenannte Batchprozesse, sehr geeignet ist.
Die aufgebrachte Kunststoffschicht kann darüber hinaus bei entsprechender Belichtung als Lötstopp und isolierender Oberflächenschutz verwendet werden, so dass sich separate Arbeitsgänge erübrigen. Das erfindungsgemässe Verfahren ermöglicht es zudem, Abdeckungen mit beliebigen Konturen klein9- rer Abmessungen herzustellen als mit anderen Mitteln. Bei anderen Verfahren oft erforderliche Zusatzmittel wie Kleber, welche die Leiterbahnen verunreinigen und Lötprozesse erschweren können, entfallen beim erfindungsgemässen Verfahren vollständig.
** WARNING ** beginning of DESC field could overlap end of CLMS **.
PATENT CLAIMS
1. A method for laterally covering a flat component on a substrate provided with conductor tracks with a liquid, curable polymer, characterized in that a border surrounding the component, the outer contour of which corresponds to the lateral boundary of the cover to be produced, by etching one onto the substrate applied, photosensitive plastic layer exposed according to the contours of the border and that after the installation of the component, the liquid polymer is brought onto the bordered area in such an amount that it covers the component and extends to the outer edge of the border, whereupon the polymer is cured.
2. The method according to claim 1, characterized in that a photosensitive plastic film is used to apply the plastic layer to the substrate.
3. Located on a substrate, covered according to the method of claim 1 component.
4. Application of the method according to claim 1 for covering a platelet-shaped semiconductor component.
The invention relates to a method for laterally covering a flat component located on a substrate provided with conductor tracks with a liquid, curable polymer.
Sensitive components that are on a substrate provided with conductor tracks, for. B. a plate made of ceramic, glass or other insulating material, must be protected by a cover against mechanical damage and harmful atmospheric agents. This is particularly the case for flat semiconductor crystals or integrated circuits which are connected to the conductor tracks via very thin wires, so-called bond wires. As a material for the cover, a drop of a liquid polymer, e.g. B. an epoxy resin or a silicone resin, which is cured after application.
The expansion of the drop occurring in the liquid state of the applied polymer must be limited laterally, since the polymer otherwise flows into a region of the conductor tracks in which subsequently, ie. H. after curing of the polymer, solder connections are to be made. In a process in use, the polymer drop is brought freely onto the component to be covered, with attempts being made to prevent its leakage by selecting the polymer with regard to its surface tension and thixotropy, and dabbing the substrate along the intended limitation of the cover with very small amounts of the polymer .
With this method, which also requires elaborate manual work, the shape of the hardened drop cannot be defined, or can only be defined very weakly or with a high reject rate. Rather, it is impossible to prevent the polymer from creeping until it cures, in particular because conductor tracks cross its edge.
A method has also already been used in which the substrate is provided with a recess or an elevated border in order to limit the liquid polymer drop. However, a recess cannot generally be formed in the substrate with the required depth, so that there is still a risk that the liquid polymer will flow out over the edge of the recess. Applying a raised border, i. H. a frame, the required height on the substrate is associated with considerable expenditure of time and money, since the borders are individually manufactured, carefully placed on the substrate and fastened to it, e.g. B.
have to be glued.
The object of the invention is to provide a method of the type mentioned which allows an exact, unchangeable and safe lateral limitation of the cover with little effort and in series operation even with an excessively large amount of the applied liquid polymer.
According to the invention, the method is characterized in that a border surrounding the component, the outer contour of which corresponds to the lateral boundary of the cover to be produced, is formed by etching a photosensitive plastic layer applied to the substrate and exposed according to the contours of the border, and that after the component has been installed the liquid polymer is brought onto the bordered area in such an amount that it covers the component and extends to the outer edge of the border, after which the polymer is cured.
The invention is based on the finding that, under the influence of the surface tension, the lateral expansion of a drop is limited by the falling outer edges of a base for the drop or a border. Thus, a border provided for the lateral delimitation of the cover of a component need only have a small height, which is considerably smaller than the height of the drop covering the component. The invention accordingly makes it possible to provide a thin plastic layer as the border, the border being produced in a very economical way by etching a photosensitive plastic layer.
Embodiments of the invention are explained below with reference to the drawing. Show it:
1 shows a schematic section through a cover of a crystal plate or the plate of an integrated circuit produced by the method according to the invention,
Fig. 2 is a schematic section similar to Fig. 1 with a different arrangement of the plate on a substrate.
1 and 2, a plate 2 is mounted on a flat substrate 1, which may consist of a plastic, ceramic or glass, for example a crystal plate, a plate of an integrated circuit or another flat component of low height. The substrate list is provided with conductor tracks 3, which can consist of a copper lamination of the substrate 1, of a conductive paste or of gold.
Connection points 4 of the plate 2 are connected to the conductor tracks 3 via thin wires 5, so-called bond wires made of aluminum or gold. Outside the connection points of the wires 5 with the conductor tracks 3 there is a raised edge 6 made of plastic, which is closed and thus encloses the plate 2 together with the wires 5, relative to the surface of the substrate 1 or the conductor tracks 3. The contour of the border 6 can be arbitrary, for. B.
circular or rectangular. The cross-section of the border 6 is approximately rectangular, the outer edge 7 of the border being sharp. The height of the border is, for example, 0.1 mm.
The inside of the border 6 is covered with a polymer 8, i. H. with a cured, originally liquid polymer, e.g. B. an epoxy resin or a silicone resin, covered or cast. According to the surfaces 9 of the polymer shown, this completely covers the plate 2 and the wires 5 and extends to the outer edge 7 or
the outer edges of the border 6. In the example of FIG. 2, the surface 9 of the covering polymer 8 is less high above the substrate 1 than in the example of FIG. 1 because
2, the plate 2 is mounted in a recess 10 of the substrate 1
The covers shown are produced in the manner described below. The substrate 1 provided with the conductor tracks 3 is provided with a photosensitive plastic layer on its surface. This plastic layer can be applied, for example, by spraying the substrate 1 with a photosensitive lacquer. Since, in order to achieve a layer thickness of approximately 0.1 mm, the lacquer must be sprayed on in several steps, it is more advantageous to apply a photosensitive film which is commercially available as a solder stop film to the substrate 1, for example by hot pressing.
The applied plastic film is then exposed in accordance with the contours of the desired border 6. The exposed plastic layer is then etched, so that only the exposed border 6 remains on the substrate 1. An undercut 11 which occurs in this case and which is indicated in FIGS. 1 and 2 is not only without disadvantage, but advantageously brings about a sharp edge 7
The substrate 1 is now equipped with the necessary components, in particular the plate 2. A drop of the liquid polymer provided as a covering or potting compound is then placed on the plate 2 in such an amount that the plate 2 together with the wires 5 is completely covered. The polymer flows here to the inner edge or the inner edges of the border 6 and then to the top of the border 6. However, the polymer drop is held on the outer edge 7 or the outer edges of the border 6, because of the large contact angle the edge 7 the adhesive tension is less than the surface tension. Thus, the polymer cannot crawl over the edge 7, even if the viscosity of the polymer initially becomes smaller during a subsequent curing, which may take place under moderate heat.
It follows that the polymer 8 shown in FIGS. 1 and 2 is independent of its height, i. H. regardless of the size of the polymer drop, can not extend beyond the outer edge 7 of the border 6.
The method according to the invention has the advantage that it allows lateral, precise, quick and cost-effective limitation of the covering of the component, so that the method is very suitable for the serial production of substrates with semiconductor components, so-called batch processes.
The applied plastic layer can also be used with appropriate exposure as a solder stop and insulating surface protection, so that separate operations are unnecessary. The method according to the invention also makes it possible to produce covers with any contours of smaller dimensions than with other means. In other processes, additives such as adhesives that are often required, which contaminate the conductor tracks and can complicate soldering processes, are completely eliminated in the process according to the invention.
Claims (4)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1332277A CH619333A5 (en) | 1977-11-01 | 1977-11-01 | Process for covering a flat component with a polymer |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1332277A CH619333A5 (en) | 1977-11-01 | 1977-11-01 | Process for covering a flat component with a polymer |
Publications (1)
Publication Number | Publication Date |
---|---|
CH619333A5 true CH619333A5 (en) | 1980-09-15 |
Family
ID=4391409
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CH1332277A CH619333A5 (en) | 1977-11-01 | 1977-11-01 | Process for covering a flat component with a polymer |
Country Status (1)
Country | Link |
---|---|
CH (1) | CH619333A5 (en) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1989000337A1 (en) * | 1987-06-29 | 1989-01-12 | Eastman Kodak Company | Encapsulation barrier for thick-film hybrid circuits |
EP0338728A2 (en) * | 1988-04-21 | 1989-10-25 | AT&T Corp. | Integrated circuit package using plastic encapsulant |
EP0470559A1 (en) * | 1990-08-07 | 1992-02-12 | Siemens Aktiengesellschaft | Method of mounting semiconductor integrated circuits |
EP0472766A1 (en) * | 1990-08-30 | 1992-03-04 | Siemens Aktiengesellschaft | Process for encapsulating a contacted semiconductor chip |
FR2677785A1 (en) * | 1991-06-17 | 1992-12-18 | Philips Composants | METHOD FOR MANUFACTURING A MICROCIRCUIT CARD |
EP0552497A2 (en) * | 1992-01-22 | 1993-07-28 | Fujikura Ltd. | Light illumination membrane switch with reduced size and improved light illumination |
WO2006102801A1 (en) * | 2005-03-26 | 2006-10-05 | Zhishan Peng | A packaging method of spot gluing liquid resin |
CN1956180B (en) * | 2005-03-26 | 2010-08-04 | 阎跃军 | Substrate structure of electronic device packed by liquid resin drip |
WO2013113660A1 (en) * | 2012-02-01 | 2013-08-08 | Osram Gmbh | Flexible led module and method for the production thereof |
EP3419393A4 (en) * | 2016-02-18 | 2019-02-27 | Mitsubishi Electric Corporation | Electronic device and manufacturing method therefor |
WO2021148438A1 (en) * | 2020-01-24 | 2021-07-29 | Robert Bosch Gmbh | Sensor casing and method for potting an open receiving space of a sensor casing |
DE102021213165A1 (en) | 2021-11-23 | 2023-05-25 | Zf Friedrichshafen Ag | Process for component protection of a printed circuit board |
-
1977
- 1977-11-01 CH CH1332277A patent/CH619333A5/en not_active IP Right Cessation
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1989000337A1 (en) * | 1987-06-29 | 1989-01-12 | Eastman Kodak Company | Encapsulation barrier for thick-film hybrid circuits |
EP0338728A2 (en) * | 1988-04-21 | 1989-10-25 | AT&T Corp. | Integrated circuit package using plastic encapsulant |
EP0338728A3 (en) * | 1988-04-21 | 1990-06-13 | American Telephone And Telegraph Company | Integrated circuit package using plastic encapsulant |
EP0470559A1 (en) * | 1990-08-07 | 1992-02-12 | Siemens Aktiengesellschaft | Method of mounting semiconductor integrated circuits |
EP0472766A1 (en) * | 1990-08-30 | 1992-03-04 | Siemens Aktiengesellschaft | Process for encapsulating a contacted semiconductor chip |
FR2677785A1 (en) * | 1991-06-17 | 1992-12-18 | Philips Composants | METHOD FOR MANUFACTURING A MICROCIRCUIT CARD |
EP0519564A1 (en) * | 1991-06-17 | 1992-12-23 | Philips Cartes Et Systemes | Method for the manufacture of a microcircuit card and microcircuit card |
EP0552497A2 (en) * | 1992-01-22 | 1993-07-28 | Fujikura Ltd. | Light illumination membrane switch with reduced size and improved light illumination |
EP0552497A3 (en) * | 1992-01-22 | 1994-06-01 | Fujikura Ltd | Light illumination membrane switch with reduced size and improved light illumination |
US5471023A (en) * | 1992-01-22 | 1995-11-28 | Fujikura Ltd. | Light illumination membrane switch with reduced size and improved light illumination |
WO2006102801A1 (en) * | 2005-03-26 | 2006-10-05 | Zhishan Peng | A packaging method of spot gluing liquid resin |
CN100356532C (en) * | 2005-03-26 | 2007-12-19 | 阎跃军 | Liquid resin dropping packaging method |
CN1956180B (en) * | 2005-03-26 | 2010-08-04 | 阎跃军 | Substrate structure of electronic device packed by liquid resin drip |
WO2013113660A1 (en) * | 2012-02-01 | 2013-08-08 | Osram Gmbh | Flexible led module and method for the production thereof |
EP3419393A4 (en) * | 2016-02-18 | 2019-02-27 | Mitsubishi Electric Corporation | Electronic device and manufacturing method therefor |
US10512168B2 (en) | 2016-02-18 | 2019-12-17 | Mitsubishi Electric Corporation | Electronic device and method of manufacturing the same |
WO2021148438A1 (en) * | 2020-01-24 | 2021-07-29 | Robert Bosch Gmbh | Sensor casing and method for potting an open receiving space of a sensor casing |
DE102021213165A1 (en) | 2021-11-23 | 2023-05-25 | Zf Friedrichshafen Ag | Process for component protection of a printed circuit board |
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