DE112017001139T5 - MICRO DEVICE INTEGRATION IN SYSTEM SUBSTRATE - Google Patents

Abstract

Post-processing steps for integrating micro devices into a system substrate (receiving substrate) or improving the performance of the micro devices after transfer. Post-processing steps for additional structures, such as reflective layers, fillers, black matrix, or other layers, may be used to enhance the decoupling or containment of the generated LED light. Dielectric and metallic layers can be used to integrate an electro-optic thin film device into the system substrate with transmitted micro devices. Color conversion layers can be integrated into the system substrate to produce different outputs from the micro devices.

Description

CROSS REFERENCE TO RELATED APPLICATION (S)

The present patent application claims the priority of U.S. Patent Application Number 15 / 060,942 , filed on 4 March 2016, to which reference is made in its entirety in this document.

FIELD OF THE INVENTION

The present disclosure relates to transferred microsystem integration on a receiving substrate. More particularly, the present disclosure relates to the post-processing steps for improving the performance of micro devices after transfer to a receiving substrate, including developing an optical structure, integrating thin-film electro-optic devices, adding color conversion layers, and properly patterning devices on one donor.

SHORT SUMMARY

Some embodiments of this description relate to post-processing steps to improve the performance of the micro devices. For example, in some embodiments, the micro device array may include micro light emitting diodes (LEDs), organic LEDs, sensors, solid state devices, integrated circuits, MEMS (micro-electro-mechanical systems), and / or other electronic components. The receptacle substrate may be, but is not limited to, a printed circuit board, a thin film transistor backplane, an integrated circuit substrate or, in the case of optical micro devices such as LEDs, a component of a display, for example a drive circuit backplane. In these embodiments, in addition to interconnecting the micro devices, post processing steps may be used for additional structures such as reflective layers, fillers, black matrix, or other layers to enhance the coupling out of the generated LED light. As another example, dielectric and metallic layers may be used to integrate an electro-optic thin film device into the system substrate with the transferred microdevices.

In one embodiment, the active area of the pixel (or subpixel) extends to be larger than the micro device using fillers, such as a dielectric. Here, the filler is patterned to define the active pixel area. Herein, an active pixel area (or subpixel area) is defined as the area emitted by the pixel (or subpixel) light produced by the micro light emitting device (or devices), or in the case of a sensor, to receive received light and to direct to a pixel (or subpixel) photochromic microdevice. In another embodiment, reflective layers are used to contain the light in the active area.

In one aspect, there is provided a method of fabricating integrated devices, the integrated device comprising a plurality of pixels, each pixel comprising at least one sub-pixel comprising a micro device integrated on a substrate, the method comprising: extending an active one Surface of a first subpixel on an area that is larger than an area of a first micro device of the first subpixel by patterning a filler layer around the first micro device and between the first micro device and at least one second micro device.

An embodiment includes making at least one reflective layer covering at least a portion of one side of the patterned fill layer, wherein the reflective layer isolates at least a portion of the incident or outgoing light in the active area of the subpixel.

In one case, the reflective layer is made as an electrode of the micro device.

In one case, the patterning of the fill layer also views the fill layer around another subpixel.

In another embodiment, the patterning of the fill layer is further performed with a dielectric fill material.

In another aspect, there is provided an integrated device comprising: a plurality of pixels, each comprising at least one sub-pixel comprising a micro device integrated on a substrate; and a patterned fill layer formed around a first micro-device of a first sub-pixel and between the first micro-device and at least one second micro-device, wherein the patterned fill layer extends an active area of the first sub-pixel to a surface larger than an area of the first micro device ,

In one case, the integrated device further comprises: at least one reflective layer comprising at least a portion of a Covered side of the patterned filling layer, wherein the reflective layer isolates at least a portion of the incident or exiting light on the active surface of the first subpixel.

In one case, the reflective layer is an electrode of the micro device.

In one embodiment, the patterned fill layer is formed around another sub-pixel.

According to another aspect, there is provided a method of fabricating an integrated device, the device comprising a plurality of pixels each comprising at least one sub-pixel comprising a micro device integrated on a substrate, the method comprising: integrating at least one micro device in a receiving substrate; and after integration of the at least one micro device, integrating at least one thin-film electro-optical device into the receiving substrate.

In some embodiments, integrating the at least one thin-film electro-optic device includes forming an optical path for the micro-device through all or some layers of the at least one electro-optic device.

In some embodiments, integrating the at least one thin film electro-optic device is such that an optical path for the microdevice passes through a surface or surface of the integrated device that is not a surface or surface of the electro-optic device.

In addition, some embodiments include fabricating an electrode of the thin-film electro-optic device, wherein the electrode of the thin-film electro-optic device defines an active area of at least one pixel and one subpixel.

Moreover, some embodiments include preparing an electrode serving as a divided electrode of both the thin-film electro-optical device and the micro light-emitting device.

In one embodiment, one of the microdevice electrodes may serve as the reflective layer.

In another embodiment, the active area may consist of several subpixels or pixels.

The active area may be greater than, less than or equal to the pixel area (or sub-pixel area).

In this description, the active pixel area and active sub-pixel area are used interchangeably. However, it will be apparent to those skilled in the art that the pixel and / or subpixel may be used in all of the embodiments described herein.

In another embodiment, the thin film electro-optic devices are deposited on the receiving substrate after the microdevices have been integrated into the receiving substrate.

In one embodiment, an optical path for the micro device is designed to emit (or absorb) light through all or some layers of the electro-optic device.

In another embodiment, the optical path for the micro device does not pass through all or some layers of the electro-optic device.

In one embodiment, the electro-optical device is a thin-film device.

In another embodiment, the electrode of the electro-optical device is used to define the active area of the pixel (or subpixel).

In another embodiment, at least one of the electrodes of the electro-optical device is shared with the micro-device electrode.

In one embodiment, color conversion material covers the surface and partially (or completely) surrounds the body of the micro device.

In one embodiment, the bank structure separates the color conversion materials.

In another embodiment, color conversion material covers the surface (and / or partially or completely the body) of the active area.

In one embodiment, the microdevices are patterned on donor substrate to conform to the array structure in the receiving substrate (system substrate). In this case, all devices in a part (or the whole) of the donor substrate transferred to the Aufhahmesubstrat.

In another embodiment, vias are created in the donor substrate to couple the micro devices on the donor substrate to the receiving substrate.

In another embodiment, the donor substrate has more than one type of micro-device, and the pattern of micro-device types on the donor substrate coincides, at least in one direction, partially or wholly with the pattern of the corresponding areas (or pads) on the system substrate.

In another embodiment, the donor substrate has more than one type of micro-device, and in at least one direction, the pitch between different microdevices in the donor substrate is a multiple of the pitch of the corresponding surfaces (or pads) on the system substrate.

In another embodiment, the donor substrate has more than one type of micro-device. In at least one direction, the pitch between two different microdevices coincides with the pitch of the corresponding areas (or pads) on the receiving substrate (or system substrate).

In one embodiment, the pattern of different types of microdevices on the donor substrate creates a two-dimensional array of each type, wherein the pitch between the respective arrays of different types coincides with the pitch of the corresponding areas on the system substrate.

In another embodiment, the pattern of different types of microdevices on the donor substrate creates a one-dimensional array, wherein the pitch of the arrays coincides with the pitch of the corresponding areas (or pads) on the system substrate.

The foregoing and additional aspects and embodiments of the present disclosure will become apparent to those of ordinary skill in the art in view of the detailed description of various embodiments and / or aspects made with reference to the drawings, a brief description of which is provided next.

list of figures

• 1 zeigt ein Aufnahmesubstrat mit Kontaktpads und ein Array übertragener Mikrovorrichtungen, die an dem Aufnahmesubstrat befestigt sind.
• 2A zeigt ein Aufnahmesubstrat mit Kontaktpads, ein Array übertragener Mikrovorrichtungen, die an dem Aufnahmesubstrat befestigt sind, und konforme dielektrische und reflektierende Schichten an der Oberseite.
• 2B zeigt ein Aufnahmesubstrat mit Kontaktpads, ein Array übertragener Mikrovorrichtungen, die an dem Aufnahmesubstrat befestigt sind, und gemusterte konforme dielektrische und reflektierende Schichten.
• 2C zeigt ein Aufnahmesubstrat mit Kontaktpads, ein Array übertragener Mikrovorrichtungen, die an dem Aufnahmesubstrat befestigt sind, gemusterte dielektrische und reflektierende Schichten und eine Schwarzmatrixschicht, die zwischen benachbarten Mikrovorrichtungen gebildet ist.
• 3A zeigt ein Aufnahmesubstrat mit Kontaktpads, ein Array übertragener Mikrovorrichtungen, die an dem Aufnahmesubstrat befestigt sind, gemusterte konforme dielektrische und reflektierende Schichten, eine Schwarzmatrixschicht und eine transparente leitfähige Schicht, die auf dem Substrat abgeschieden ist.
• 3B zeigt ein Aufnahmesubstrat mit einem integrierten Array übertragener Mikrovorrichtungen, die an dem Aufnahmesubstrat befestigt sind, und optische reflektierende Bauteile zur Verbesserung der Lichtauskopplung.
• 3C zeigt ein Aufnahmesubstrat mit einem integrierten Array übertragener Mikrovorrichtungen, die an dem Aufnahmesubstrat befestigt sind, und konkave Kontaktpads zur Verbesserung der Lichtauskopplung.
• 3D zeigt ein Aufnahmesubstrat mit einem integrierten Array übertragener Mikrovorrichtungen, die an dem Aufnahmesubstrat in einer Unterseitenemissionsausgestaltung befestigt sind.
• 3E zeigt ein Aufnahmesubstrat mit einem integrierten Array übertragener Mikrovorrichtungen, die an dem Aufnahmesubstrat befestigt sind.
• 4A zeigt ein Aufnahmesubstrat mit übertragenen Mikrovorrichtungen, einer konformen dielektrischen Schicht und einer verbundenen reflektierenden Schicht.
• 4B zeigt ein Aufnahmesubstrat mit übertragenen Mikrovorrichtungen, konformer dielektrischer Schicht, verbundener reflektierender Schicht und einer transparenten leitfähigen Schicht, abgeschieden auf dem Substrat.
• 5 zeigt ein Aufnahmesubstrat mit übertragenen Mikrovorrichtungen und einen gemusterten Füllstoff, der die Pixel (oder Subpixel) definiert.
• 6A zeigt eine pixelierte Füllstruktur, die alle Subpixel in mindestens einem Pixel (zum Beispiel beide Subpixel bei einem Pixel bedeckt, das aus zwei Subpixeln hergestellt ist) bedeckt.
• 6B zeigt ein Pixel, das aus zwei Subpixeln hergestellt ist, eine Füllschicht, die gemustert ist, um das Pixel zu definieren, und gemusterte konforme dielektrische und reflektierende Schichten um das Pixel.
• 6C zeigt ein Pixel, das aus zwei Subpixeln hergestellt ist, eine Füllschicht, die gemustert ist, um das Pixel zu definieren, gemusterte konforme dielektrische und reflektierende Schichten um das Pixel und eine Schwarzmatrixschicht, die um das Pixel gewickelt ist.
• 6D zeigt ein Pixel, das aus zwei Subpixeln hergestellt ist, eine Füllschicht, die gemustert ist, um das Pixel zu definieren, gemusterte konforme dielektrische und reflektierende Schichten um das Pixel, eine Schwarzmatrixschicht, die um das Pixel gewickelt ist, und eine transparente leitfähige Schicht, abgeschieden auf dem Substrat.
• 6E zeigt ein Pixel, das aus zwei Subpixeln hergestellt ist, mit reflektierenden optischen Bauteilen auf dem Aufnahmesubstrat für bessere Lichtauskopplung.
• 6F zeigt ein Pixel, das aus zwei Subpixeln hergestellt ist, mit konkaven Kontaktpads auf dem Aufhahmesubstrat.
• 6G zeigt ein Pixel, das aus zwei Subpixeln hergestellt ist, mit einer Unterseitenemissionsausgestaltung.
• 6H zeigt ein Pixel, das aus zwei Subpixeln hergestellt ist, mit einer Unterseitenemissionsausgestaltung, einer gemeinsamen oberen Elektrode und Seitenreflektoren.
• 7 zeigt ein Aufhahmesubstrat mit zwei Kontaktpads.
• 8 zeigt ein Aufnahmesubstrat mit einer übertragenen Mikrovorrichtung, die auf eines der Kontaktpads gebondet ist.
• 9 zeigt die Integration einer übertragenen Mikrovorrichtung mit einer elektro-optischen Dünnfilmvorrichtung in einer Hybridstruktur.
• 10 zeigt ein anderes Beispiel einer Integration einer übertragenen Mikrovorrichtung mit einer elektro-optischen Dünnfilmvorrichtung in einer Hybridstruktur.
• 11 zeigt ein Beispiel der Integration einer übertragenen Mikrovorrichtung mit einer elektro-optischen Dünnfilmvorrichtung in einer Hybridstruktur mit einer gemeinsamen oberen Elektrode.
• 12 zeigt eine Ausführungsform für die Integration einer übertragenen Mikrovorrichtung mit einer elektro-optischen Dünnfilmvorrichtung in einer Dualoberflächenhybridstruktur mit sowohl oberen als auch unteren transparenten Elektroden.
• 13A zeigt eine andere Ausführungsform für ein Systemsubstrat und eine integrierte Mikrovorrichtung mit Dünnfilm-elektro-optischer Vorrichtung.
• 13B zeigt eine andere Ausführungsform eines Systemsubstrats und eine integrierte Mikrovorrichtung mit einer Dünnfilm-elektro-optischen Vorrichtung.
• 14A zeigt eine abgewandelte Ausführungsform eines Systemsubstrats und eine integrierte Mikrovorrichtung mit zwei Dünnfilm-elektro-optischen Vorrichtungen.
• 14B zeigt ein Beispiel eines Systemsubstrats und eine integrierte Mikrovorrichtung mit zwei Dünnfilm-elektro-optischen Vorrichtungen und einer reflektierenden Schicht auf dem Aufnahmesubstrat.
• 15 veranschaulicht einen Querschnitt eines Systemsubstrats und eines Mikrovorrichtungssubstrats.
• 16 zeigt den Ausrichtungsschritt für ein Systemsubstrat und ein Mikrovorrichtungssubstrat in einem Übertragungsprozess.
• 17 zeigt den Bondingschritt für ein Systemsubstrat und ein Mikrovorrichtungssubstrat in einem Übertragungsprozess.
• 18 zeigt den Mikrovorrichtungssubstrat-Entfernschritt für ein Systemsubstrat und ein Mikrovorrichtungssubstrat in einem Übertragungsprozess.
• 19 zeigt den Opferschicht-Entfernschritt für ein Systemsubstrat und ein Mikrovorrichtungssubstrat in einem Übertragungsprozess.
• 20 zeigt den Schritt zur Bildung der gemeinsamen Elektrode für ein Systemsubstrat und ein Mikrovorrichtungssubstrat in einem Übertragungsprozess.
• 21 ist ein Querschnitt eines Mikrovorrichtungssubstrats mit einer Füllschicht(en).
• 22 ist ein Querschnitt eines Mikrovorrichtungssubstrats bedeckt mit einer Stützschicht.
• 23 zeigt den Mikrovorrichtungssubstrat-Entfernschritt für ein Mikrovorrichtungssubstrat in einem Übertragungsprozess.
• 24A zeigt den Opfer-/Pufferschicht-Entfernschritt für ein Mikrovorrichtungssubstrat in einem Übertragungsprozess. Ein Systemsubstrat mit Kontaktpads ist ebenfalls gezeigt.
• 24B zeigt die freiliegenden Mikrovorrichtungen nach dem Entfernen der Opfer-/Pufferschicht.
• 25 zeigt den Bondingschritt für ein Systemsubstrat und ein Mikrovorrichtungssubstrat in einem Übertragungsprozess.
• 26A zeigt den Stützschicht-Entfernschritt für ein Mikrovorrichtungssubstrat in einem Übertragungsprozess. Ein Systemsubstrat mit Kontaktpads und übertragenen Mikrovorrichtungen ist ebenfalls gezeigt.
• 26B zeigt die freiliegenden Mikrovorrichtungen nach Entfernen der Stützschicht und der Füllschicht.
• 27 ist ein Querschnitt eines Mikrovorrichtungssubstrats, das mit einer Füllschicht bedeckt ist.
• 28A ist ein Querschnitt eines Mikrovorrichtungssubstrats mit Durchgangslöchern in dem Substrat und der Opferschicht.
• 28B ist der in 28A gezeigte Querschnitt nach Entfernen der Pufferschicht.
• 29 ist ein Querschnitt eines Mikrovorrichtungssubstrats mit Durchgangslöchern in dem Substrat und der Opferschicht, bedeckt von einer isolierenden Schicht.
• 30 ist ein Querschnitt eines Mikrovorrichtungssubstrats mit einer leitfähigen Schicht, die über Durchgangslöcher in dem Substrat gefüllt ist, und der Opferschicht.
• 31 ist ein Querschnitt eines Mikrovorrichtungssubstrats mit einer gemeinsamen oberen Elektrode.
• 32 ist ein Querschnitt eines integrierten Systemsubstrats mit einer gemeinsamen oberen Elektrode.
• 33A zeigt eine zweidimensionale Anordnung von Mikrovorrichtungen in einem Donatorsubstrat.
• 33B ist ein Querschnitt eines Systemsubstrats und eines Mikrovorrichtungssubstrats.
• 34 ist ein Querschnitt eines gebondeten Systemsubstrats und Mikrovorrichtungssubstrats.
• 35 zeigt den Laser-Lift-Off-Schritt für ein Mikrovorrichtungssubstrat in einem Übertragungsprozess.
• 36 ist ein Querschnitt eines Systemsubstrats und eines Mikrovorrichtungssubstrats nach dem selektiven Übertragungsprozess.
• 37 zeigt ein integriertes Systemsubstrat mit einer gemeinsamen oberen Elektrode.
• 38A ist ein Querschnitt eines Mikrovorrichtungssubstrats mit Mikrovorrichtungen, die unterschiedliche Höhen aufweisen.
• 38B ist der in 38A gezeigte Querschnitt, nachdem die Pufferschicht gemustert worden ist.
• 39 ist ein Querschnitt eines Mikrovorrichtungssubstrats mit einer Füllschicht.
• 40 zeigt den Ausrichtungsschritt für ein Systemsubstrat mit Spannmechanismen und ein Mikrovorrichtungssubstrat in einem Übertragungsprozess.
• 41A zeigt eine zweidimensionale Anordnung von Mikrovorrichtungen in einem Donatorsubstrat.
• 41B ist ein Querschnitt eines Systemsubstrats und eines Mikrovorrichtungssubstrats mit unterschiedlichen Teilungen (Pitches).
• 42 zeigt den selektiven Mikrovorrichtungsübertragungsprozess für ein Systemsubstrat und ein Mikrovorrichtungssubstrat mit unterschiedlichen Teilungen (Pitches).
• 43 ist ein Querschnitt eines Systemsubstrats und eines Mikrovorrichtungssubstrats mit unterschiedlichen Teilungen (Pitches).
• 44 zeigt den selektiven Mikrovorrichtungsübertragungsprozess für ein Systemsubstrat und ein Mikrovorrichtungssubstrat mit unterschiedlichen Teilungen (Pitches).
• 45 zeigt ein integriertes Mikrovorrichtungssubstrat.
• 46A zeigt den Übertragungsprozess von Mikrovorrichtungen auf ein Systemsubstrat mit einer Planarisierungsschicht, einer gemeinsamen oberen Elektrode, Bankstrukturen und Farbumwandlungselementen.
• 46B zeigt die Struktur von 46A mit dem Zusatz einer gemeinsamen Elektrode, die auf der Planarisierungsschicht gebildet ist.
• 47 zeigt eine Struktur mit Farbumwandlung zum Definieren der Farbe der Pixel.
• 48 zeigt eine Struktur mit konformer gemeinsamer Elektrode und Farbumwandlung, die von einer Bankschicht getrennt sind.
• 49 zeigt eine Struktur mit konformer Farbumwandlung, die von einer Bankschicht getrennt ist.
• 50 zeigt eine Struktur mit Farbumwandlungselementen auf der gemeinsamen Elektrode ohne die Bankschicht.
• 51 zeigt eine Struktur mit konformer gemeinsamer Elektrode und Farbumwandlung.
• 52 zeigt eine Struktur mit konformen Farbumwandlungselementen, die direkt auf den Mikrovorrichtungen gebildet sind.
• 53A zeigt eine Struktur mit Farbumwandlung zum Definieren der Pixelfarbe, eine Planarisierungsschicht und eine gemeinsame transparente Elektrode.
• 53B zeigt die Struktur von 53A nach dem Bilden der Einkapselungsschicht.
• 54A zeigt eine Struktur mit Farbumwandlung zum Definieren der Pixelfarbe und ein separates Substrat zum Einkapseln.
• 54B zeigt die Struktur von 54B, nachdem das Substrat, das mit der Einkapselungsschicht beschichtet ist, an das integrierte Systemsubstrat gebondet ist.
• 55A zeigt eine Struktur mit einem Systemsubstrat mit Kontaktpads und ein separates Donatorsubstrat mit Mikrovorrichtungen.
• 55B zeigt die Struktur von 55A nach der Übertragung der Mikrovorrichtungen auf das Systemsubstrat.
• 55C zeigt die Struktur von 55B nach dem Nachverarbeiten, um eine gemeinsame Elektrode und Farbumwandlungsschichten abzuscheiden.

The foregoing and other advantages of the disclosure will become apparent upon reading the following detailed description and upon reference to the drawings.

• 1 Fig. 10 shows a receiving substrate with contact pads and an array of transferred micro devices attached to the receiving substrate.
• 2A Figure 11 shows a receiving substrate with contact pads, an array of transferred micro devices mounted on the receiving substrate, and conformal dielectric and reflective layers on the top.
• 2 B Fig. 10 shows a receiving substrate with contact pads, an array of transferred micro devices mounted on the receiving substrate, and patterned conformal dielectric and reflective layers.
• 2C Fig. 10 shows a receiving substrate with contact pads, an array of transferred micro devices mounted on the receiving substrate, patterned dielectric and reflective layers, and a black matrix layer formed between adjacent micro devices.
• 3A Figure 11 shows a receiving substrate with contact pads, an array of transferred micro devices mounted on the receiving substrate, patterned conformal dielectric and reflective layers, a black matrix layer, and a transparent conductive layer deposited on the substrate.
• 3B Fig. 10 shows a receiving substrate having an integrated array of transferred micro devices mounted on the receiving substrate and optical reflective components for improving light extraction.
• 3C Fig. 10 shows a receiving substrate with an integrated array of transferred micro devices mounted on the receiving substrate and concave contact pads for improving light extraction.
• 3D Fig. 10 shows a receiving substrate having an integrated array of transferred micro devices attached to the receiving substrate in a bottom-side emitting configuration.
• 3E shows a receptacle substrate with an integrated array of transferred micro devices attached to the receptacle substrate.
• 4A shows a receiving substrate with transmitted micro devices, a compliant dielectric layer and a bonded reflective layer.
• 4B shows a receiving substrate with transferred microdevices, conformal dielectric layer, associated reflective layer and a transparent conductive layer deposited on the substrate.
• 5 Figure 4 shows a receiving substrate with transferred micro devices and a patterned filler defining the pixels (or subpixels).
• 6A Figure 12 shows a pixelized fill structure covering all subpixels in at least one pixel (for example, covering both subpixels for a pixel made of two subpixels).
• 6B Figure 4 shows a pixel made of two sub-pixels, a fill layer patterned to define the pixel, and patterned conformal dielectric and reflective layers around the pixel.
• 6C For example, a pixel made up of two subpixels, a fill layer patterned to define the pixel, patterned conformal dielectric and reflective layers around the pixel, and a black matrix layer wrapped around the pixel.
• 6D Figure 4 shows a pixel made of two sub-pixels, a fill layer patterned to define the pixel, patterned conformal dielectric and reflective layers around the pixel, a black matrix layer wrapped around the pixel, and a transparent conductive layer. deposited on the substrate.
• 6E shows a pixel made of two sub-pixels with reflective optical components on the receiving substrate for better light extraction.
• 6F shows a pixel made of two sub-pixels with concave contact pads on the receiving substrate.
• 6G Fig. 12 shows a pixel made of two subpixels with a bottom emission embodiment.
• 6H Fig. 10 shows a pixel made of two subpixels with a bottom emission design, a common top electrode, and side reflectors.
• 7 shows a Aufhahmesubstrat with two contact pads.
• 8th shows a receptacle substrate with a transferred micro device bonded to one of the contact pads.
• 9 shows the integration of a transferred micro device with an electro-optical thin-film device in a hybrid structure.
• 10 shows another example of integration of a transferred micro device with an electro-optical thin-film device in a hybrid structure.
• 11 shows an example of the integration of a transferred micro device with an electro-optical thin-film device in a hybrid structure with a common upper electrode.
• 12 shows an embodiment for the integration of a transferred micro device with an electro-optical thin-film device in a dual-surface hybrid structure with both upper and lower transparent electrodes.
• 13A shows another embodiment for a system substrate and a thin film electro-optic device integrated micro device.
• 13B shows another embodiment of a system substrate and a micro device integrated with a thin-film electro-optical device.
• 14A shows a modified embodiment of a system substrate and an integrated micro device with two thin-film electro-optical devices.
• 14B Fig. 12 shows an example of a system substrate and an integrated micro device with two thin-film electro-optic devices and a reflective layer on the receiving substrate.
• 15 illustrates a cross section of a system substrate and a micro device substrate.
• 16 shows the alignment step for a system substrate and a micro device substrate in a transfer process.
• 17 shows the bonding step for a system substrate and a micro device substrate in a transfer process.
• 18 shows the micro device substrate removal step for a system substrate and a micro device substrate in a transfer process.
• 19 shows the sacrificial layer removal step for a system substrate and a micro device substrate in a transfer process.
• 20 shows the step of forming the common electrode for a system substrate and a micro device substrate in a transfer process.
• 21 Figure 10 is a cross section of a micro device substrate with a fill layer (s).
• 22 FIG. 12 is a cross section of a micro device substrate covered with a support layer. FIG.
• 23 shows the micro device substrate removal step for a micro device substrate in a transfer process.
• 24A shows the sacrificial / buffer layer removal step for a micro device substrate in a transfer process. A system substrate with contact pads is also shown.
• 24B shows the exposed micro devices after removal of the sacrificial / buffer layer.
• 25 shows the bonding step for a system substrate and a micro device substrate in a transfer process.
• 26A Fig. 10 shows the support layer removal step for a micro device substrate in a transfer process. A system substrate with contact pads and transferred micro devices is also shown.
• 26B shows the exposed micro devices after removal of the backing layer and the fill layer.
• 27 FIG. 12 is a cross section of a micro device substrate covered with a fill layer. FIG.
• 28A FIG. 12 is a cross section of a micro device substrate having through holes in the substrate and the sacrificial layer. FIG.
• 28B is the in 28A Cross section shown after removal of the buffer layer.
• 29 FIG. 12 is a cross section of a micro device substrate having through holes in the substrate and the sacrificial layer covered by an insulating layer. FIG.
• 30 FIG. 12 is a cross section of a micro device substrate with a conductive layer filled via through holes in the substrate and the sacrificial layer. FIG.
• 31 FIG. 12 is a cross section of a micro device substrate having a common top electrode. FIG.
• 32 FIG. 12 is a cross-section of an integrated system substrate having a common upper electrode. FIG.
• 33A shows a two-dimensional array of micro devices in a donor substrate.
• 33B FIG. 12 is a cross section of a system substrate and a micro device substrate. FIG.
• 34 FIG. 12 is a cross-section of a bonded system substrate and micro-device substrate. FIG.
• 35 shows the laser lift-off step for a micro device substrate in a transfer process.
• 36 FIG. 12 is a cross-section of a system substrate and a micro device substrate after the selective transfer process. FIG.
• 37 shows an integrated system substrate with a common upper electrode.
• 38A Figure 12 is a cross section of a micro device substrate with micro devices having different heights.
• 38B is the in 38A shown cross section after the buffer layer has been patterned.
• 39 is a cross-section of a micro device substrate with a fill layer.
• 40 shows the alignment step for a system substrate with tensioning mechanisms and a micro-device substrate in a transfer process.
• 41A shows a two-dimensional array of micro devices in a donor substrate.
• 41B FIG. 12 is a cross section of a system substrate and a micro device substrate having different pitches. FIG.
• 42 shows the selective micro device transfer process for a system substrate and a micro device substrate with different pitches.
• 43 FIG. 12 is a cross section of a system substrate and a micro device substrate having different pitches. FIG.
• 44 shows the selective micro device transfer process for a system substrate and a micro device substrate with different pitches.
• 45 shows an integrated micro-device substrate.
• 46A shows the transfer process of micro devices on a system substrate with a planarization layer, a common top electrode, bank structures and color conversion elements.
• 46B shows the structure of 46A with the addition of a common electrode formed on the planarization layer.
• 47 shows a color conversion structure for defining the color of the pixels.
• 48 FIG. 12 shows a conformal common electrode color conversion structure separated from a bank layer. FIG.
• 49 shows a conformal color conversion structure separated from a bank layer.
• 50 shows a structure with color conversion elements on the common electrode without the bank layer.
• 51 shows a structure with conformal common electrode and color conversion.
• 52 shows a structure with conformal color conversion elements formed directly on the micro devices.
• 53A FIG. 12 shows a color conversion structure for defining the pixel color, a planarization layer and a common transparent electrode. FIG.
• 53B shows the structure of 53A after forming the encapsulating layer.
• 54A shows a color conversion structure for defining the pixel color and a separate encapsulating substrate.
• 54B shows the structure of 54B after the substrate coated with the encapsulant layer is bonded to the integrated system substrate.
• 55A Figure 4 shows a structure with a system substrate with contact pads and a separate donor substrate with micro devices.
• 55B shows the structure of 55A after transferring the micro devices to the system substrate.
• 55C shows the structure of 55B after post-processing to deposit a common electrode and color conversion layers.

While the present disclosure may be subject to various modifications and alternative forms, specific embodiments or embodiments have been shown by way of example in the drawings and will be described in detail herein. It should be understood, however, that the disclosure is not intended to be limited to the specific forms disclosed. Rather, the disclosure is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of an invention as defined by the appended claims.

DETAILED DESCRIPTION

The development process of a system based on micro devices consists of pre-processing the devices on a donor substrate (or a temporary substrate), transferring the micro devices from the donor substrate to the receiving substrate, and post-processing to enable device functionality. The preprocessing step may include patterning and adding bonding elements. The transfer process may include bonding a pre-selected array of micro devices to the receiving substrate followed by removal of the donor substrate. Several different selected transmission processes have already been developed for microdevices. After integration of the microdevices into the receiving substrate, additional post-processing processes may be performed to produce required functional connections.

In this disclosure, "emitting device" is used to describe different integration and postprocessing methods. However, one skilled in the art will appreciate that other devices, such as sensors, may be used in these embodiments. For example, in the case of sensor micro devices, the optical path will be similar to that of emissive micro devices, but in the opposite direction.

Some embodiments of this disclosure relate to post-processing steps to improve the performance of the micro devices. For example, in some embodiments, the micro device array may include micro light emitting diodes (LEDs), organic LEDs, sensors, solid state devices, MEMS (micro-electro-mechanical systems), and / or other electronic components. The receptacle substrate may be, but is not limited to, a printed circuit board, a thin film transistor backplane, an integrated circuit substrate or, in the case of optical micro devices such as LEDs, a component of a display, for example a driver circuit backplane. In these embodiments, in addition to interconnecting the micro devices, post processing steps may be used for additional structures such as reflective layers, fillers, black matrix, or other layers to enhance the coupling out of the generated LED light. In another example, dielectric and metallic layers may be used to integrate an electro-optic thin film device into the system substrate with the transferred micro devices.

In one embodiment, the active area of the pixel (or subpixel) is extended to be larger than the micro device by using fillers (or a dielectric). Here, the filler is patterned to define the active area of the pixel (the active area is the area that emits light or absorbs incoming light). In another embodiment, reflective layers are used to contain the light in the active area.

In one embodiment, the reflective layer may be one of the micro device electrodes.

In another embodiment, the active area may consist of several subpixels or pixels.

The active area may be greater than, less than or equal to the pixel area (sub-pixel area).

In another embodiment, thin film electro-optic devices are deposited in the receiving substrate after the microdevices are integrated into the receiving substrate.

In one embodiment, an optical path for the micro device is designed to emit (or absorb) light through all or some layers of the electro-optic device.

In another embodiment, the optical path for the micro device does not pass through all or some layers of the optoelectronic device.

In one embodiment, the optoelectronic device is a thin film device.

In another embodiment, the electrode of the electro-optical device is used to define the active area of the pixel (or subpixel).

In another embodiment, at least one of the electrodes of the electro-optical device is shared with the micro-device electrode.

In one embodiment, color conversion material covers the surface and partially (or completely) surrounds the body of the micro device.

In one embodiment, the bank structure separates the color conversion materials.

In another embodiment, color conversion material covers the surface (and / or partially or completely the body) of the active area.

In one embodiment, the microdevices are patterned on donor substrate to conform to the array structure in the receiving substrate (system substrate). In this case, all devices in a part of (or in the whole) donor substrate are transferred to the receiving substrate.

In another embodiment, vias are provided in the donor substrate to couple the micro devices on the donor substrate to the receiving substrate.

In another embodiment, the donor substrate has more than one type of microdevice, and in at least one direction, the pattern of microdevice types on the donor substrate partially or completely matches the pattern of the corresponding areas (or pads) on the system substrate.

In another embodiment, the donor substrate has more than one type of micro-device, and in at least one direction, the pitch between different microdevices in the donor substrate is a multiple of the pitch of the corresponding area (or pads) on the system substrate.

In another embodiment, the donor substrate has more than one type of micro-device. In at least one direction, the pitch between two different microdevices coincides with the pitch of the corresponding areas (or pads) on the receiving substrate (or system substrate).

In one embodiment, the pattern of different types of microdevices on the donor substrate creates a two-dimensional array of each type where the pitch between the respective arrays of different types coincides with the pitch of the corresponding areas on the system substrate.

In another embodiment, the pattern of different types of microdevices on the donor substrate provides a one-dimensional array where the pitch of the arrays coincides with the pitch of the corresponding areas (or pads) on the system substrate.

1 shows a receiving substrate 100 , Contact pads 101 and 101b and micro devices 102 and 102b in an array on the receiving substrate 100 are attached. contact pads 101 on which the micro devices 102 are transferred, are in an array on the receiving substrate 100 , microdevices 102 are transferred from a donor substrate and to the contact pads 101 bonded. microdevices 102 may be any micro device typically fabricated in sheet-like lots, including, but not limited to, LEDs, OLEDs, sensors, solid state devices, integrated circuits, MEMS and / or other electronic components.

As in 2A can be shown in an embodiment in which the micro devices 102 Micro LEDs are a conformal dielectric layer 201 and a reflective layer 202 be formed over the bonded micro-LEDs. In some embodiments, the conformal dielectric layer is 201 0.1 to 1 μm thick, and may be deposited by any one of a number of different thin film deposition techniques. The conformal dielectric layer 201 isolates the micro-LED sidewalls from the reflective layer 202 , Additionally, the dielectric layer passivates and protects 201 the micro-LED sidewalls. The conformal dielectric layer 201 may also be the upper surface of the receiving substrate 100 between adjacent micro-LED devices 102 and 102b cover. The conforming reflective layer 202 can over the dielectric layer 201 be deposited. The reflective layer 202 may be a single layer or made up of multiple layers. A series of conductive materials can be considered the reflective layer 202 be used. In some embodiments, the conformal reflective layer 202 a metallic double layer with a total thickness of up to 0.5 microns.

Regarding 2 B can the dielectric layer 201 and the reflective layer 202 can then be patterned using, for example, lithographic patterning and etching to form the top surface of the micro LEDs 102 partially uncover. In an embodiment in which the micro-LEDs are integrated into a backplane of a display system, also with reference to FIG 2C , can be a black matrix 203 between adjacent micro-LEDs 102 and on the reflective layer 202 be formed to reduce the reflection of the ambient light. In one example, the black matrix 203 a layer of resins such as polyimide or polyacrylic in which particles of black pigment such as carbon black are dissolved. In some embodiments, the thickness of the black matrix 203 0.01 to 2 microns. This layer can be patterned and etched to the top surface of the micro LEDs 102 to expose, as in 2C shown. Optionally, the thickness of the black matrix 203 be constructed to the integrated substrate 100 to planarize. In another embodiment, a planarization layer, which may be made of organic insulating material, is formed and patterned to planarize the backplane substrate.

Regarding 3A can be a transparent conductive layer 301 be deposited on the substrate conforming to the black matrix 203 and the top surface of the micro LEDs 102 covered. In some embodiments, the transparent electrode 301 0.1 to 1 μm thick oxide layers, including, but not limited to, indium tin oxide (ITO) and aluminum doped zinc oxide. In a case where the integrated package is a display structure, the transparent electrode may 301 the common electrode of the micro-LED devices 102 be.

Optionally, the reflective layer 202 as a conductivity enhancer for the transparent electrode 301 be used. In this case, part of the reflective layer can not be black matrixed 203 or other Planarisierungsschichten be covered so that the transparent electrode layer 301 with the reflective layer 202 can connect.

In another embodiment, in 3B can be a reflective or other type of optical component 302 on the substrate 100 be formed to the decoupling of light from the micro device 102 and 102b was produced to improve. The common contact 301 is transparent to allow light to pass through this layer. These structures can be referred to as upper emission structures.

Regarding 3C can the contact pad 101 be formed to have a concave or otherwise shaped structure to the coupling of light from the micro device 102 is produced to improve. The contact pad shape is not limited to the concave shape and may have other shapes depending on the light emission characteristics of the micro device.

In an embodiment with reference to 3D For example, the structure is configured to emit light from the substrate. In these bottom emission structures, the substrate may be 100 be transparent, and the common electrode 303 is designed to be reflective for better light extraction.

In another embodiment, in 3E is shown, the reflective layer 202 extend to the micro devices too cover and also act as the common upper electrode.

Regarding 4A In another embodiment, the dielectric layer 201 be deposited and patterned before the reflective layer 202 is formed. As in 4 This can be a direct contact between micro LEDs 102 and the reflective layer 202 allow that as a common upper contact for the micro devices 102 can be used. It can be a black matrix 203 or, alternatively, a planarization layer.

Regarding 4B may in other embodiments a common transparent electrode 301 and / or other optical layers at the top of the substrate 100 deposited to improve conductivity and / or light outcoupling.

One of the main challenges of optoelectronic microdevices is the void space between adjacent microdevices. Display systems with this structural property can create an image artifact called a "screen-lattice effect." In one embodiment, the micro-device sizes may be optically extended to be equal to or greater than the micro-device size. In one embodiment, in 5 is shown, after transferring the array of micro devices 102 from the donor to the receiving substrate 100 , transparent filler 501 deposited and patterned to define the pixel (or subpixel). In one example, the filler size may be the smaller or the maximum size possible in a pixel area (or sub-pixel area). In another example, the filler size may be larger than the pixel area or the sub-pixel area. The filler may have a different or similar shape to the pixel area on the system substrate. The processes in 3 and 4 can then be used to enhance the light extraction from the micro devices.

Regarding 6A is in an embodiment in which the pixel 601 from two subpixels 601 and 601b is made, the filler 501 patterned to the active area of the pixel 601 (where the active area is defined as the area from which the display emits light). Here, the active area may be less than, greater than or equal to the size of the pixel area (or sub-pixel area). As in 6B . 6C and 6D can be shown, processes in 2 and 3 be applied. This design affects the discoloration at the edges due to the separation between subpixels.

Regarding 6B can be a dielectric layer 201 and a reflective layer 202 around / over pixels 601 be formed.

With reference also to 6C can be a black matrix 203 between adjacent pixels and around each pixel to reduce the reflection of the ambient light.

Regarding 6D can be a transparent conductive layer 301 are deposited on the substrate, which is the black matrix 203 and the top surface of the micro LEDs 601 and 601b covered.

In another embodiment, in 6E may be a reflective or other optical component 602 on the substrate 100 be formed to the decoupling of light from the micro devices 101 and 101b is produced to improve. The common contact 301 is transparent, so that the light is emitted through this layer. These structures may be referred to as top emission structures.

Regarding 6F can the contact pad 101 be formed to have a concave structure to the decoupling of light, the micro device 101 is produced to improve. The contact pad shape is not limited to the concave shape and may have other shapes depending on the light emission characteristics of the micro device.

Regarding 6G In another embodiment, the structure is formed to emit light from the substrate. In these bottom emission structures, the substrate may be 100 be transparent, and the common electrode 303 is designed to be reflective for better light extraction.

In another embodiment, in 6H is shown, the reflective layer 202 may be extended to cover the micro devices and also act as the common top electrode.

In other embodiments, the aforementioned pixel definition structure may cover more than one pixel (or subpixel).

In another case, a reflective layer or pads on the receiving substrate may be used to cover the receiving substrate and provide a reflective surface before the microdevices are transferred for better light outcoupling.

In all the aforementioned embodiments, the reflective layer may also be opaque be. In addition, the reflective layers may be used as one of the micro device electrodes or as one of the system substrate interconnects (electrode, signal, or power line). In another embodiment, the reflective layer may be used as a touch electrode. The reflective layers may be patterned to act as a touch screen electrode. In one case, they may be patterned in vertical and horizontal directions to form the contact screen crossing electrode. In this case, a dielectric between vertical and horizontal tracks can be used.

HYBRID STRUCTURES

In another embodiment, a thin-film electro-optical device is integrated into the receiving substrate after the micro-device arrays have been transferred to the receiving substrate.

7 shows a receiving substrate 100 and contact pads 702 to which the micro device arrays are transferred and into which the thin film electro-optic device is integrated in a number of hybrid structure embodiments.

Regarding 8th can the micro device 801 on the bonding pad 702a of the receiving substrate 100 be transferred and bonded. In one case, as in 9 shown a dielectric layer 901 above the substrate 100 formed to cover the exposed electrodes and conductive layers. Lithography and etching can be used to form the dielectric layer 901 to look at. The conductive layer 902 is then deposited and patterned around the lower electrode of the thin-film electro-optical device 904 to build. If there is no risk of unwanted coupling between lower electrode 902 and other conductive layers in the receiving substrate, the dielectric layer 901 be omitted. However, this dielectric layer may also function as a planarization layer to better fabricate electro-optic devices 904 to offer.

Continue with reference to 9 becomes a bank layer 903 on the substrate 100 deposited to the edges of the electrode 902 and the micro device 801 to cover. A thin film electro-optical device 904 is then formed over this structure. Organic LED devices (OLEDs) are an example of such a thin film electro-optic device that can be formed using a variety of techniques, such as but not limited to shadow masking, lithography, and printing patterning. Finally, the upper electrode 905 the electro-optical thin-film device 904 deposited and patterned, if necessary.

In an embodiment in which the thickness of the micro devices 801 is significantly high, can cause cracks or other structural problems in the lower electrode 902 occur. In these embodiments, a planarization layer may be used together with the dielectric layer 901 or without them being used to tackle this problem.

In another embodiment, in 10 can be shown, the micro device 801 a device electrode 1001 exhibit. This electrode may be common to other micro devices in the system substrate. In this case, the planarization layer (if present) and / or bank structure covers 903 the electrode 1001 to eliminate any short circuits between the electro-optical device 904 and the device electrode 1001 to avoid.

Regarding 11 In one embodiment, the upper electrode 905 thin-film electro-optical device 904 with the micro device 801 be connected through an opening in the planarization layer. In this case, the electro-optical device 904 be selectively formed so that it does not cover this opening.

In another case, the lower electrode of the micro device may be shared between the thin film electro-optical device and the transferred micro device.

Regarding 12 in another example, the lower electrode 902 thin-film electro-optical device 904 over the micro device 801 be extended. If the micro device 801 must have a transparent path to the outside through its upper electrode, the lower electrode must 902 (if it is not transparent) have an opening over the micro device (for example, as in FIG 13A shown in connection with another embodiment). In this case, the opening of the bank layer 903 also be covered. The opening is not limited to the specific structure used in 12 is illustrated and can be developed with different methods.

Continue with reference to 12 can the micro device 801 a transparent path through the substrate 100 through when the electrode 702 is transparent. In a case where a transparent path through its upper electrode is required, either the lower electrode must be used 902 and the upper electrode of the micro device must be transparent, or it must have an opening in the lower electrode 902 be. 13A shows a layout structure in which the lower electrode 902 an opening to a transparent path through the upper electrode 905 to enable. It can be an opening 1301 in the bank layer 903 for the common upper electrode 905 be. If there is no common upper electrode 905 there and if the bank layer 903 is transparent, the opening is in the bank layer 903 not required. In some embodiments, when the top electrode is 905 is also opaque, an opening in the upper electrode 905 also required for a topside emission.

Regarding 13B in another embodiment, the lower electrode covers 902 the micro device 801 not to provide a transparent path for the micro device 801 provide. It can be an opening 1301 in the bank layer 903 for a common upper electrode. If there is no common electrode and the bank layer 903 is transparent, the opening is in the bank layer 903 not required.

In another case, the contact of the thin-film electro-optical device may be extended to function as a reflective layer. As in 14A As can be seen, the two juxtaposed pixels can control the light coming from the micro device 801 is generated, in which pixels curb. In another embodiment, in 14B is shown, the reflective layer 1401 on the surface of the substrate 100 more of the light to the upper electrode 905 reflect. Consequently, the coupling out of the light that is from the micro device 801 is generated, improved. In this case, the best practice is to make either both the top and bottom electrodes of the thin-film electro-optic device transparent, or to make openings when those electrodes are opaque.

In another embodiment, the thin-film electro-optic devices and micro devices may be on two opposite sides of the system substrate. In this case, the circuits of the system substrate may either be on one side of the system substrate and connected to the other side via vias, or the circuits may be on both sides of the system substrate.

In another case, the micro device may be on one system substrate and the thin film electro-optic device on another system substrate. These two substrates can then be bonded together. In this case, the circuit may be on one of the system substrates or on both substrates.

INTEGRATION

1. 1. Vorderseitiges Bonden
2. 2. Rückseitiges Bonden
3. 3. Substratbonden über Verbindungskontaktloch

This document also discloses various methods for integrating a monolithic array of micro devices into a system substrate or selectively transferring an array of micro devices to a system substrate. Here the proposed processes are divided into two categories. In the first category, the pitch of the bonding pads on the system substrate is the same as the pitch of the bonding pads on the microdevices. In the second category, the bonding pads on the system substrate have a larger pitch compared to that of the micro devices. For the first category, three different integration or transmission schemes are presented.

1. 1. Front bonding
2. 2. Back bonding
3. 3. Substrate bonding via connection via hole

In this embodiment, micro devices may be of the same type or different types in terms of functionality. In one embodiment, the micro devices are micro LEDs of the same color or a variety of different colors (eg, red, green, and blue), and the system substrate is the backplane that controls individual micro LEDs. Such multicolor LED arrays are fabricated directly on a substrate or transferred to a temporary substrate from the build substrate. In an example that is in 15 have been shown to be RGB micro-LED devices 1503 . 1504 and 1505 on a sacrificial / buffer layer 1502 and the substrate 1501 built up. In one case, the system substrate 1506 , the contact pads 1507 has, aligned ( 16 ) and to the micro device substrate 1501 be bonded, as in 17 shown. After removing the micro device substrate 1501 ( 18 ) and the sacrificial / buffer layer 1502 ( 19 ) may be a filler dielectric coating 2001 (eg polyimide resist) are spin-coated / deposited on the integrated sample ( 20 ). This step may be followed by an etching process to expose the tops of the micro-LED devices. In the case of micro-LED devices, a common transparent electrode 2002 be deposited on the sample. In another embodiment, an upper electrode may be deposited and patterned to isolate micro devices for subsequent processes.

In another embodiment, as in 21 shown the micro devices 1503 . 1504 and 1505 on a buffer / sacrificial layer 1502 built up. A dielectric filling layer 2101 is deposited on the substrate / rotationally coated to completely cover the microdevices. In an example that is in 21 is illustrated, this step is followed by an etching process to the tops of the micro devices 1503 . 1504 and 1505 in order to form the upper common contact and the seed layer for subsequent processes (eg electroplating). Regarding 22 then becomes a thick mechanical support layer 2102 deposited on the tops of the sample, built or bonded. Here is the filling layer 2101 a black matrix layer or a reflective material. Also, an electrode (either as a patterned or a common layer) may be deposited before the mechanical support is deposited. The mechanical support layer is then deposited. In the case of optoelectronic devices such as LEDs, the mechanical support layer must be transparent. As in 23 and 24 is shown, the micro device substrate 1501 or the sacrificial / buffer layer is then removed using various processes such as laser lift-off or etching. In one case, the thickness of the substrate is initially reduced to a few microns using processes such as, but not limited to, Deep Reactive Ion Etching (DRIE). The remaining substrate is then removed by processes such as, but not limited to, a wet chemical etch process. In this case, the buffer / sacrificial layer 1502 act as an etch stop layer to ensure a uniform etched substrate and to avoid any damage to the micro devices. After removing the buffer layer 1502 , as in 24 As shown, another etch (eg, Reactive Ion Etching - RIE) is performed to expose the microdevices. A metallic layer may be deposited and patterned to serve as upper contact and bonding pads for the micro devices, if not formed during fabrication of the micro device. The system substrate 1506 , the contact pads 1507 can then be aligned and bonded to the micro device array, as in FIG 25 shown. Depending on the type and functionality of the micro devices, the mechanical support layer may 2102 and filling layer 2101 then be removed, as in 26A and 26B shown.

In other embodiments, interconnect contact holes are implemented by the substrate to make contacts to the backside of the microdevices.

Regarding 27 In one embodiment, the micro devices may 1503 . 1504 and 1505 Multi-color micro-LEDs that are on an insulating buffer layer 1502 were built. This buffer layer may also function as an etch stop layer. A dielectric layer 2701 is deposited as a filling layer.

Regarding 28A and 28B become patterns on the back of the substrate 1501 using processes such as, but not limited to, photolithography. In one embodiment, a method such as DRIE is used to make holes through the substrate in the substrate 1501 manufacture. The buffer layer 1502 which may function as an etch stop layer may be removed using, for example, a wet etch process, as shown in FIG 28B illustrated.

Regarding 29 becomes an insulating film 2901 on the back of the substrate 1501 deposited. This insulating layer 2901 may be partially from the back of the micro devices 1503 . 1504 and 1505 are removed to allow the formation of electrical contacts to these micro devices.

Regarding 30 become the through holes with a conductive material 3001 filled using processes such as, but not limited to, electroplating. Here, the connection via holes may function as the micro device contacts and bonding pads.

As in 31 illustrates, becomes a common front contact 3101 the micro devices 1503 . 1504 and 1505 is formed by performing an etching process (eg, using RIE) to expose the tops of the microdevices, followed by the deposition of a transparent conductive layer around the front contact 3101 to build.

Regarding 32 then becomes the micro device substrate 1501 aligned and to the system substrate 1506 bonded, the contact pads 1507 which, in this example, may be a backplane that controls individual devices.

In another embodiment, micro devices have been fabricated on a substrate with arbitrary pitches to maximize production yield. For example, the micro devices may be multicolor micro LEDs (eg RGB). The system substrate for this example may be a display backplane having contact pads having a different pitch from that of the micro LEDs.

Regarding 33A has the donor substrate 1501 in one embodiment, micro device types 3301 . 3302 and 3303 on, and these are in the form of one-dimensional arrays 3304 patterned, in which it is for each micro device 3301 . 3302 or 3303 a type at least one Micro device of another type whose pitch is 3305 coincides with the pitch of the corresponding areas (or pads) on the receiving substrate (or system substrate).

As an example, in one embodiment, which is incorporated in 33B shown is the pitch 3404 the contact pads 1507 twice larger than the pitch 3402 the micro devices 3401 , as in 33 shown.

Regarding 34 become the system substrate 1506 and the micro device substrate 1501 brought together, aligned and brought into contact.

As in 35 and 36 As shown, methods such as laser lift-off (LLO) can be used to manipulate the microdevices 3401 selectively on the contact pads 3403 on the system substrate 1506 transferred to. As in 37 shown, the transfer of the deposition of a filling layer 3701 and a conformal conductive layer 3702 be followed on top of the system substrate as a common electrode.

In another embodiment, in 38 is shown is a buffer layer 3801 as a material template for making the micro devices 1503 . 1504 and 1505 required.

Continue with reference to 38A and 38B becomes the buffer layer 3801 on the sacrificial layer 1502 deposited and patterned to micro devices 1503 . 1504 and 1505 to isolate. In some cases, the sacrificial layer may as well 1502 be patterned.

In one embodiment, rather than isolating individual microdevices, groups of microdevices may be isolated from each other (as in FIG 38 shown) to simplify the transmission process.

Regarding 39 can be a filler 3901 such as, but not limited to, polyimide may be spin-coated on the substrate to fill the gap between the individual microdevices. This filling step ensures the mechanical strength during the transfer process. This is especially important when using a process such as laser lift-off to release micro devices from the carrier substrate.

Regarding 40 For example, micro devices may not have the same height, making them difficult to bond to the system substrate. In these cases, an electrostatic clamping mechanism 4001 or another clamping mechanism may be implemented in the system substrate to temporarily hold the micro devices on the system substrate for the final bonding steps. The clamping mechanism may be local to micro devices or global stress to a group of micro devices, as in the case of the same pitch transfer for the whole wafer. The tensioning mechanism may be on a layer above the contact electrode. In this case, a planarization layer can be used.

In an embodiment with reference to 41A forms the pattern of different micro device types 3301 . 3302 and 3303 on the donor substrate a two-dimensional array of the respective type (for example, array 4100 ), where the pitch (pitch) between the arrays 4101 , which is defined as the pitch between adjacent arrays, matches the pitch of the corresponding area on the system substrate.

In one embodiment, in 41B and 42 is shown is the micro device substrate 1501 when the sub-device pitch (pitch) 4101 greater than the normal distance between fabricated individual micro devices on their substrate (e.g., in large displays), designed as two-dimensional single color arrays. Here are the contact pad division (-Pitch) 4102 and micro device array division (pitch) 4103 equal. Using this technique, the manufacturing requirements of the microdevices can be relaxed and the selected transfer process can be reduced compared to that described above.

43 and 44 show an alternative pattern in which micro devices are not formed in two-dimensional groups and the different micro devices are uniformly placed over the substrate for three different micro devices, as in FIG 43 shown.

Regarding 45 In another embodiment, micro devices are first deposited on a conductive semitransparent common substrate 4501 then transfer them to a system substrate 4502 bonded.

COLOR TRANSFORMATION STRUCTURE

In some embodiments, where micro devices are optical devices such as LEDs, either color conversion or color filters can be used to define a different functionality (different colors in the case of pixels). In this embodiment, two or more contact pads on the system substrate are populated with the same type of optical device. Once placed, the devices on the system substrates then become distinguished according to different color conversion layers.

Regarding 46A and 46B In one embodiment, the whole structure is a planarization layer 4601 covered after micro devices 1503 on the system substrate 1506 were transferred. A common electrode 4602 is then on the planarization layer 4601 educated. The planarization layer may be the same height or higher or lower than the stacked devices. If the planarization layer is lower (or there is no planarization layer), the wall of the device may be conformally covered by passivation materials.

Regarding 47 becomes a bank structure 4701 (especially when a printing process is used to deposit the color conversion layers). The bank can separate every pixel or just different color conversion materials 4702 separate.

48 shows an integrated structure in which the color conversion layer 4702 completely covers the top of the transferred micro devices and partially covers their sides. Bank 4701 separates the color conversion layers 4702 , and the electrode 4602 is a common contact for all transmitted micro devices.

49 shows an integrated structure in which the color conversion layer 4702 completely covers the top of the transferred micro devices and partially covers their sides. Bank 4701 separates the color conversion layers, and contacts to the micro devices are only across the system substrate 1506 produced.

50 shows an integrated structure in which the color conversion layer directly on the common electrode 4602 is formed. In this case, no bank layer is used.

51 shows an integrated structure in which the color conversion layer 4702 completely covers the top of the transferred micro devices and partially covers their sides. The electrode 4602 is a common contact for all transmitted micro devices. In this case, no bank layer is used.

52 shows an integrated structure in which the color conversion layer 4702 completely covers the top of the transferred micro devices and partially covers their sides. The contacts to the micro devices are made only through the system substrate. In this case, no bank layer is used.

In one embodiment, in 53A and 53B is shown, a planarization layer 5301 deposited on the structure after the color conversion material 4702 on the integrated system substrate 1506 is formed. In some instances, where the color conversion material and / or other components of the integrated substrate must be protected from environmental conditions, an encapsulating layer is formed 5302 formed over the entire structure. It should be noted that the encapsulation layer 5302 may be formed from a stack of different layers to effectively protect the integrated substrate from environmental conditions.

Regarding 54A and 54B may be a separate substrate in another embodiment 5401 that with the encapsulation layer 5302 coated to the integrated system substrate.

The embodiments that are in 53 and 54 can be combined, wherein the encapsulation layer 5302 is formed on both the structure and on the separate substrate for more efficient encapsulation.

The common electrode is a transparent conductive layer which is deposited on the substrate in the form of a blanket. In one embodiment, this layer may function as a planarization layer. In some embodiments, the thickness of this layer is chosen to meet both optical and electrical requirements.

The distance between the optical devices may be made large enough to reduce crosstalk between the optical devices, or a blocking layer may be deposited between the optical devices to achieve this. In one case, the planarization layer also functions as a blocking layer.

After the color conversion layers are deposited, different layers such as polarizers can be deposited.

In another aspect, color filters are deposited on the color conversion layers. In this case, a wider color spectrum and higher efficiency can be achieved. A planarization layer and / or bank layer after the color conversion layer may be used before the color filter layers are deposited.

The color filters may be larger than the color conversion layer to prevent any loss of light To block. In addition, a black matrix can be formed between the color conversion islands or color filters.

55A . 55B and 55C illustrate structures in which the device is shared by a few pixels (or sub-pixels). Here is the micro device 1503 not completely patterned, but the horizontal state is constructed so that the contacts 1507 define the area associated with each pixel. 55A shows the system substrate 1506 with contact pads 1507 and a donor substrate 1501 with micro devices 1503 , After the micro devices 1503 on the system substrate (shown in FIG 55B ), a post-processing ( 55C ), such as depositing a common electrode 4602 , of color conversion layers 4702 , Color filters and so on. 55C shows an example of deposition of color conversion layers 4702 on top of the micro device 1503 , However, the methods described in this disclosure and another possible method may be used.

It is possible to add the color conversion layers into active pixel areas (or sub-pixel areas) after forming the active area as described. This may provide a higher fill factor and higher performance and also avoid color leakage from the side pixel (or subpixel) when the active area of the pixel (or subpixel) is covered by reflective layers.

While particular embodiments and applications of the present disclosure have been disclosed and described, it is to be understood that the present disclosure is not limited to the precise construction and compositions described herein and that various modifications, changes and variations of the foregoing descriptions may be apparent without departing from the spirit and scope of an invention as defined in the appended claims.

QUOTES INCLUDE IN THE DESCRIPTION

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

Cited patent literature

• US 15060942 [0001]

Claims (15)

Claimed is: A method of fabricating an integrated device, the integrated device comprising a plurality of pixels each comprising at least one subpixel, comprising a micro device integrated on a substrate, the method comprising: Extending an active area of a first subpixel to an area larger than an area of a first micro device of the first subpixel by patterning a fill layer around the first micro device and between the first micro device and at least one second micro device. Method according to Claim 1 further comprising: forming at least one reflective layer covering at least a portion of one side of the patterned fill layer, the reflective layer serving to contain at least a portion of incident or outgoing light in the active area of the subpixel. Method according to Claim 2 wherein the reflective layer is made as an electrode of the micro device. Method according to Claim 1 In addition, the patterning of the fill layer also scans the fill layer for another subpixel. Method according to Claim 1 Moreover, the patterning of the filling layer is carried out with a dielectric filling material. Integrated device comprising: a plurality of pixels, each comprising at least one subpixel, comprising a micro device integrated on a substrate; and a patterned fill layer surrounding a first micro device of a first subpixel and is formed between the first microdevice and at least one second microdevice, the patterned fill layer extending an active area of the first subpixel to an area larger than an area of the first microdevice. Integrated device according to Claim 6 and further comprising: at least one reflective layer covering at least a portion of one side of the patterned filler layer, the reflective layer serving to contain at least a portion of incident and outgoing light on the active surface of the first subpixel. Integrated device according to Claim 7 wherein the reflective layer is an electrode of the micro device. Integrated device according to Claim 7 wherein the patterned fill layer is formed around another sub-pixel. A method of fabricating an integrated device, the device comprising a plurality of pixels, each comprising at least one subpixel, comprising a micro device integrated on a substrate, the method comprising: Integrating at least one micro device into a receiving substrate; and subsequent to the integration of the at least one micro device, integrating at least one thin-film electro-optical device into the receiving substrate. Method according to Claim 10 wherein integrating the at least one thin-film electro-optic device comprises forming an optical path for the micro-device through all or some layers of the at least one electro-optic device. Method according to Claim 10 wherein integrating the at least one thin-film electro-optic device is such that an optical path for the micro-device passes through a surface or surface of the integrated device that is other than a surface or surface of the electro-optic device. Method according to Claim 10 and further comprising fabricating an electrode of the thin-film electro-optic device, wherein the electrode of the thin-film electro-optic device defines an active area of at least one of a pixel and a subpixel. Method according to Claim 10 and further comprising preparing an electrode serving as a divided electrode of both the thin-film electro-optical device and the micro light-emitting device.

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