KR20200008936A - High precision shadow mask deposition system and method - Google Patents

Abstract

A direct deposition system is disclosed that forms a high resolution material pattern on a substrate. Atoms evaporated from the evaporation source pass through the pattern of through holes in the shadow mask and are deposited on the substrate in the desired pattern. The shadow mask is held in a mask chuck that allows the shadow mask and the substrate to be spaced a distance that may be less than 10 microns. Before reaching the shadow mask, the evaporated atoms pass through a collimator that acts as a spatial filter that blocks all atoms that do not move along a direction that is nearly perpendicular to the substrate surface. Evaporated atoms passing through the shadow mask show little or no lateral diffusion after passing through the through hole, and the material is deposited on the substrate in a pattern with a very high fidelity with the through hole pattern of the shadow mask.

Description

High precision shadow mask deposition system and method

This application claims the priority of U.S. Provisional Patent Application No. 62 / 340,793 filed on May 24, 2016 (Agent No. 6494-208PR1), which is incorporated herein by reference in its entirety. This application also claims U.S. Regular Patent Application No. 15 / 597,635, filed May 17, 2017 (Agent No. 6494-208US1) and U.S. Regular Patent Application No. 15, filed May 23, 2017. / 602,939 (Agent No. 6494-209US1), which are incorporated by reference in their entirety.

The present invention relates generally to thin film deposition, and more particularly to evaporation based thin film deposition.

Shadow-mask-based deposition is a process of depositing a layer of material on the surface of a substrate where a desired pattern of that layer is defined during the self deposition process. This is a deposition technique and is often referred to as "direct patterning."

In a typical shadow mask deposition process, the desired material is evaporated in a source located at a distance from the substrate, and a shadow mask is placed between the substrate and the source. As evaporated atoms of material move towards the substrate, these atoms pass through a set of through-holes in the shadow mask located just in front of the substrate surface. The through holes ( ie apertures) are arranged in a desired pattern for the material on the substrate. As a result, the shadow mask passes through the through-holes and blocks the passage of all evaporated atoms except the atoms deposited on the substrate surface in the desired pattern. Shadow mask based deposition is similar to the silk-screening technique used to form patterns ( eg, uniform numbers, etc.) on clothing articles or the stenciling technique used to develop works of art.

Shadow mask based deposition has been used in the integrated circuit (IC) industry for many years to deposit patterns of materials on substrates, in part because shadow mask based deposition may deposit a material layer and then pattern the material layer. Because there is no need. As a result, its use eliminates the need to expose harmful chemicals (eg, acid-based etchant, corrosive photolithography developing chemicals, etc.) to pattern the deposited material. In addition, shadow mask based deposition requires less handling and processing of the substrate, thereby reducing the risk of substrate breakage and increasing manufacturing yield. Also, because many materials, such as organic materials, cannot be treated with photolithographic chemistry without damaging the material, the deposition of such materials by shadow masks is essential.

Unfortunately, the feature resolution that can be obtained by conventional shadow mask deposition is because the deposited material tends to diffuse laterally after passing through the shadow mask (called "feathering"). Is reduced. Feathering increases with the separation distance between the substrate and the shadow mask. To mitigate feathering, this separation is kept as small as possible without compromising the integrity of the chuck holding the substrate and shadow mask. In addition, any non-uniformity in this spacing over the deposition area will cause a change in the amount of feathering. Such non-uniformity may arise, for example, from a lack of parallelism between the substrate and the shadow mask, bending or sagging of one or both of the substrate and the shadow mask, and the like.

Unfortunately, it can be difficult to position the shadow mask and the substrate close enough to not cause a significant amount of feathering. In addition, the shadow mask should be supported only at its periphery so as not to block the passage of evaporated atoms into the through-hole pattern. As a result, the center of the shadow mask may be sag due to gravity, which may exacerbate the feathering problem.

Thus, in practice, important features formed by prior art shadow mask based deposition techniques are separated by a relatively large area of open space to accommodate feathering, which limits the device density that can be obtained. For example, each pixel of an active matrix organic light emitting diode (AMOLED) display generally includes several areas of organic light emitting material, each area emitting light of a different color. Due to feathering issues, conventional AMOLED displays are typically limited to about 600 ppi (pixels per inch) or less, which is insufficient for many applications such as near-to-eye augmented reality applications and virtual reality applications. Has been. In addition, the need for large gaps in and between pixels leads to a reduction in pixel fill factor, thereby reducing display brightness. As a result, the current density through the organic layer must be increased to provide the desired brightness, which can negatively affect the display lifetime.

Another method uses a shadow mask with an aperture as large as the active area of the display itself to deposit a monochromatic white luminescent organic layer over the entire display, and then pattern or deposit the red, green and blue color filters on top of the OLED. will be. These color filters can absorb all emitted white light except the red, green or blue portions of the spectrum (depending on the color filter) to produce a full color image. However, these color filters absorb up to 80% of the emitted light, significantly reducing display brightness, and also require operation at currents higher than the desired drive current.

The need for a process that enables high resolution direct patterning remains unmet in the prior art.

The present invention enables high resolution direct deposition of a patterned material layer on a substrate without having some of the costs and disadvantages of the prior art. Embodiments of the present invention filter the propagation angle of evaporated atoms to a narrow range in a direction approximately perpendicular to the surface of the substrate. As a result, feathering of the deposited material outside the lateral dimensions of the feature of the shadow mask is relaxed. Embodiments of the present invention are particularly well suited for use in the deposition of photosensitive materials such as organic light emitting materials. Embodiments of the present invention are also well suited for the deposition of other thin and thick film layers for packaging applications, integrated circuit processing applications, and the like.

The invention also allows for high precision alignment of the substrate with the shadow mask which can be contacted or can be spaced only a few microns apart. The present invention also provides relief of gravity-induced sag caused by the gravity of the shadow mask, which is supported only at the periphery of the shadow mask. Embodiments of the present invention are particularly suitable for applications requiring high density patterns of materials on a substrate, such as high density pixel displays (DPDs), high definition displays, and the like.

An exemplary embodiment of the present invention is a direct-patterning deposition system in which material is deposited on the surface of a substrate after the material evaporates at the source and passes through the aperture pattern of the shadow mask. The atoms to be evaporated pass through the collimator before reaching the shadow mask, which blocks all evaporated atoms except the evaporated atoms with a propagation angle close to the direction perpendicular to the substrate surface. As a result, the lateral deviation between the aperture and each region of the deposited material is reduced compared to the prior art.

The collimator includes a plurality of channels having a high height-to-width aspect ratio, wherein the longitudinal axis of the channel is substantially aligned with the vertical direction. As a result, evaporated atoms that move along directions other than those close to the vertical direction are blocked by the inner wall of the channel.

In some embodiments, the source is sized and arranged to provide a conically shaped vapor plume of vaporized atoms such that the entire substrate surface simultaneously receives the vaporized material. In some of these embodiments, the source is moved along a path such that the uniformity of the thickness of the deposited material is improved over a two dimensional area of the substrate surface.

In some embodiments, the source is a linear source that emits a scalloped vapor column, the linear source being moved along a direction that is not aligned with its longitudinal axis. In some of these embodiments, the source is moved along a direction substantially perpendicular to both the longitudinal axis of the source and the vertical direction. In some of these embodiments, the source is moved along a nonlinear path.

In some embodiments, the source comprises a plurality of individual nozzles, each nozzle emitting a conical vapor column, as a result of which the nozzles aggregate a stream of evaporated atoms that is substantially uniform over an area of the substrate surface. Will be provided as

In some embodiments, the source is a two-dimensional planar source arranged opposite to the substrate such that when heated, the organic material evaporates uniformly over the planar surface of the two-dimensional planar source. In some embodiments, relative motion is provided between the source and the shadow mask to improve the thickness uniformity of the deposited material over the two dimensional region of the substrate surface.

Another exemplary embodiment of the present invention is a direct patterning comprising a first chuck having a first mounting surface for holding a substrate and a second chuck having a second mounting surface for holding a shadow mask comprising a pattern of through holes. Deposition system. The second chuck includes a frame surrounding the central opening that exposes the pattern of through holes of the shadow mask. As a result, during deposition, evaporated atoms of material can pass through the second chuck and the through-holes and be deposited in a desired pattern on the deposition region in front of the substrate.

The first chuck produces a first electrostatic force that is selectively applied to the backside of the substrate. The first chuck is also sized and arranged such that it does not protrude above the front surface of the substrate. In a similar manner, the second chuck generates a second electrostatic force that is selectively applied to the back side of the shadow mask. The second chuck is also sized and arranged such that it does not protrude above the front of the shadow mask. Once the shadow mask and the substrate are aligned for deposition, no portion of the first chuck and the second chuck intrudes into the three-dimensional space between the substrate and the shadow mask. As a result, the substrate and shadow mask can be placed very close during deposition, or even contacted, to mitigate feathering.

In some embodiments, at least one of the first attraction force and the second attraction force is a force other than static electricity, such as a force generated in a vacuum, a magnetic force, and the like.

In some embodiments, the second mounting surface is sized and arranged to create a tensile stress on the front side of the shadow mask that mitigates the sag caused by gravity of the central area of the shadow mask. In some such embodiments, the frame of the second chuck is shaped such that its mounting surface is inclined from the upper edge of the inner perimeter of the frame. As a result, when the shadow mask is mounted on the second chuck, the shadow mask bends slightly, causing tensile stress on the front surface of the shadow mask. In some of these embodiments, the mounting surface is curved downward from the upper edge of the inner circumference of the frame.

An embodiment of the present invention is a system for depositing a first material on a plurality of deposition points in a deposition region of a substrate, the plurality of deposition points being arranged in a first arrangement, the substrate having a first major surface, and the And a second major surface comprising a deposition region, the system comprising: a source for providing a first plurality of evaporated atoms of the first material—each evaporated atoms of the first plurality of evaporated atoms Propagates along a propagation direction characterized by a propagation angle with respect to a first direction perpendicular to a first plane defined by the substrate, wherein the range of propagation angles of the first plurality of evaporated atoms is in a first angle range. Over-W; A shadow mask comprising a plurality of through holes arranged in said first arrangement, said shadow mask comprising a third major surface and a fourth major surface comprising said through holes; A first chuck for holding the substrate, the first chuck sized and arranged to selectively impart a first attractive force on the first major surface; A second chuck for holding the shadow mask, the second chuck comprising a frame surrounding a first opening that allows the material to pass through the second chuck and pass through the through hole, the second chuck Is sized and arranged to selectively impart a second attractive force on the third major surface; A collimator comprising a plurality of channels, wherein the collimator is between the source and the shadow mask, each channel of the plurality of channels having only evaporated atoms having a propagation angle within a second angle range less than the first angle range. Sized and arranged to pass through; And a positioning system that controls the relative position of the first chuck and the second chuck to align the shadow mask with the substrate.

Another embodiment of the present invention is a system for depositing a first material on a plurality of deposition points in a deposition region of a substrate, the plurality of deposition points being arranged in a first arrangement, the substrate having a first major surface, and And a second major surface having a first lateral range, the system comprising: a source operative to provide a plurality of evaporated atoms, each evaporated atom of the plurality of evaporated atoms having a propagation direction defining a propagation angle Moving along the plurality of propagation angles within a first angular range; A shadow mask comprising a plurality of through holes arranged in said first arrangement, said shadow mask comprising a third major surface and a fourth major surface comprising said through holes, said shadow mask and said plurality of deposition points collectively Define an acceptable angle range less than the first angle range; A first chuck for holding the substrate; A second chuck for retaining the shadow mask, the second chuck including a frame surrounding a first opening that allows the material to pass through the second chuck and pass through the through hole, the shadow mask and When the substrate is aligned, the shadow mask and the substrate collectively define a second region, the second region having (1) a second lateral range equal to or greater than the first lateral range, ( 2) has a thickness equal to the separation distance between the substrate and the shadow mask, (3) excludes the first chuck and the second chuck, and the first chuck and the second chuck are sized such that their thickness is less than 10 microns And arranged—and; A collimator positioned between the source and the shadow mask, the collimator comprising a plurality of channels, each channel of the plurality of channels defining a height-to-width aspect ratio that defines a filtered angular range below an acceptable range; Have

Yet another embodiment of the present invention is a method of depositing a first material on a plurality of deposition points arranged in a first arrangement on a substrate, the substrate having a first major surface, and a second major surface having a first lateral range. Wherein the second major surface comprises a first region, the method comprising: a first plurality of evaporated in a collimator positioned between a source and a shadow mask having a plurality of through holes arranged in the first arrangement Receiving atoms, the shadow mask comprising a third major surface, and a fourth major surface comprising the through hole, wherein the first plurality of evaporated atoms are characterized by a first propagation angle range and; Maintaining the substrate in a first chuck that selectively imparts a first attractive force on the first major surface; Maintaining the shadow mask in a second chuck that selectively imparts a second attractive force on the third major surface, wherein the second chuck allows particles comprising the material to pass through the through hole through the second chuck. To enable-and; Selectively passing a second plurality of evaporated atoms through the collimator to the shadow mask, wherein the second plurality of evaporated atoms is characterized by a second propagation angle range narrower than the first propagation angle range and; Positioning the substrate and the shadow mask such that the second major surface and the fourth major surface are separated by a distance of 10 microns or less; Allowing at least some of the second plurality of evaporated atoms to be deposited on the substrate through the second chuck and the plurality of through holes.

1 is a schematic diagram of a cross section of a salient feature of a direct patterned deposition system according to the prior art.
2 is a schematic diagram of a cross section of a salient feature of a high precision, direct patterned deposition system in accordance with an exemplary embodiment of the present invention.
3 illustrates the operation of a method of depositing a patterned material layer directly on a substrate in accordance with an exemplary embodiment.
4A and 4B are schematic views illustrating a plane and a cross section, respectively, of a mask chuck according to an exemplary embodiment.
5 is a cross-sectional view of the shadow mask 106 mounted on the mask chuck 206.
6A schematically illustrates a cross section of a portion of a mask chuck 206 in accordance with a first alternative embodiment of the present invention.
6B schematically illustrates a cross section of a portion of a mask chuck 206 according to a second alternative embodiment of the present invention.
7A and 7B schematically illustrate a plane and a cross section, respectively, of a mask chuck according to a third alternative embodiment of the invention.
8A is a schematic cross-sectional view of a mask chuck in accordance with an exemplary embodiment.
8B schematically illustrates a cross section of the substrate chuck 204 while holding the substrate 102.
9 is a schematic illustration of a cross section of a portion of system 100 with substrate 102 and shadow mask 106 aligned for deposition of material 116.
FIG. 10 schematically illustrates an enlarged view of a pixel region of a substrate 102 and the aperture 120 of its shadow mask 106.
11A is a schematic diagram of a cross-sectional view of a collimator in accordance with an exemplary embodiment.
11B and 11C schematically show plan and cross-sectional views of regions of the collimator 208, respectively.

1 is a schematic diagram of a cross section of a salient feature of a direct patterned deposition system according to the prior art. System 100 is a conventional evaporation system that deposits a desired pattern of material on a substrate by evaporating the material through a shadow mask located in front of the substrate. System 100 includes a source 104 and a shadow mask 106, which are arranged in a low pressure vacuum chamber (not shown).

Substrate 102 is a glass substrate suitable for the formation of an Active-Matrix Organic Light Emitting Diode (AMOLED) display. The substrate 102 includes a surface 114 that defines a plane 108 and a vertical axis 110. Vertical axis 110 is orthogonal to plane 108. The surface 114 includes a plurality of deposition points G for receiving a material emitting green light, a plurality of deposition points B for receiving a material emitting blue light, and a material emitting red light. A plurality of deposition points R for receiving. The deposition points are arranged into a plurality of pixel regions 112, whereby each pixel region includes one deposition point for the luminescent material of each color.

Source 104 is a crucible for evaporating material 116, which is an organic material that emits light at a desired wavelength. In the example shown, material 116 is an organic light emitting material that emits red light. In the example shown, the source 104 is a single chamber crucible centered relative to the substrate 102; In some embodiments, source 104 includes a plurality of chambers arranged in a one-dimensional array and / or a two-dimensional array. When material 116 is melted or sublimed in the low pressure atmosphere of vacuum chamber 110, vaporized atoms 122 of material 116 are released from the source and propagate substantially in a ballistic manner towards substrate 102. . The evaporated atoms emitted by the source 104 collectively define a vapor plume 124.

The shadow mask 106 is a plate of structural material that includes the aperture 120. The shadow mask is substantially flat and defines plane 118. The shadow mask is located between the source 104 and the substrate 102 to block the passage of all evaporated atoms except atoms that penetrate the aperture. The shadow mask and the substrate are spaced apart by a distance S (typically tens or hundreds of microns), the planes 108 and 118 are substantially parallel, and the aperture 120 is aligned at the deposition point R.

Ideally, when depositing the red light emitting material 116, the evaporated atoms are only incident onto the deposition point R. Unfortunately, vapor column 124 includes evaporated atoms moving along many different propagation directions 126, many of which are not aligned in the direction of vertical axis 110. As a result, most of the evaporated atoms passing through the aperture 120 are moving along the direction of propagation with important lateral components. The point of incidence of each evaporated valence surface 114 is due to its propagation angle and the spatial relationship between the substrate and the shadow mask, specifically the spacing S and the alignment of the aperture 120 with the deposition point R. Determined geometrically. For the purposes of this specification, including the appended claims, the term “propagation angle” refers to a vertical direction 128 that is aligned with a direction perpendicular to the plane 108 of the substrate 102 ( ie , aligned with the vertical axis 110). Is defined as the angle formed by the direction of propagation of the evaporated atoms relative to. For example, the evaporated atoms 122 move along the propagation direction 126 forming a propagation angle θp with respect to the vertical axis 128.

The propagation angle of the evaporated atoms of the vapor column 124 spans a relatively large angular range of −θ m to + θ m, which causes a major disadvantage for the prior art direct deposition systems. In particular, this results in the deposition of material 118 on the front surface 114 outside of the periphery of the aperture 120, which is generally referred to as "feathering". Also, the amount of feathering at the aperture increases with the distance of its opening from the center of the substrate 102.

For an aperture located near the center of the vapor column 124, the vaporized atoms 122 reaching the shadow mask 106 have a propagation angle that is within a relatively small angular range. That is, the evaporated atoms move along a direction in which only a slight misalignment with the vertical axis 110 occurs. As a result, evaporated atoms passing through this aperture show only minimal lateral drift (ie, feathering) after passing through the shadow mask. Thus, in this region, the lateral extent of the deposited material 116 is typically nearly aligned with the edge of the aperture 120 ( ie , the evaporated atoms are mainly deposited at the targeted deposition point R).

However, for the aperture further away from the center of the vapor column 124, the vaporized atoms arriving at the shadow mask span a relatively large angular range and include a propagation angle closer to | θm |. As a result, in these regions, the lateral distance traveled by the evaporated atoms after passing through the shadow mask becomes larger, resulting in the deposited material feathering out far beyond the lateral range of the aperture. This causes a lateral offset δf between the edge of the aperture opening and the periphery of the region where the material 116 is deposited. Thus, the deposited material extends beyond the area of the targeted deposition point. In some cases, such feathering may induce deposition of material on adjacent deposition points ( ie , deposition point B and / or deposition point G) intended for different luminescent materials, resulting in mixing of colors. have.

It should be noted that the feathering is caused by any additional misalignment between the shadow mask and the substrate, for example a deviation from the parallelism of the planes 108 and 118 ( i.e. , the relative pitch between the mask and the substrate). And / or yaw), unevenness of the shadow mask and / or substrate, and translation and / or rotational misalignment between the shadow mask and the substrate. In addition, in many prior art deposition systems ( eg, systems for depositing more than one material, etc.), the source 104 is located off-center from the substrate, which further increases the feathering problem.

Those skilled in the art will appreciate that placing the shadow mask 106 in contact with the substrate 102 during deposition will alleviate or even eliminate the feathering problem. Unfortunately, this is undesirable or impossible in many cases, for a variety of reasons. First, prior art substrate and shadow mask chucks typically include features protruding over the substrate and shadow mask, respectively. As a result, these features serve as a blocking element that limits how closely the substrate and shadow mask can be located. Second, contact with the shadow mask can damage structures present on the surface of the substrate. Third, damage to the shadow mask may occur due to contact with the substrate. Fourth, residue may remain on the shadow mask surface when separated from contact with the substrate. Frequent cleaning of the shadow mask is then required, which increases the processing time and overall cost, while causing the possibility of mask damage during the cleaning operation. As a result, prior art shadow mask deposition has been substantially limited to non-contact configurations in which feathering has a significant negative impact. Fifth, conventional shadow masks are usually made of metal, which inevitably becomes quite thick. When placed in contact with the substrate, thick shadow masks cause shadowing within each opening area to make the edges of the deposited features thinner. In the case of thicker shadow masks such as those commonly used in the prior art, more material is lost due to the thinner edges of the walls of the aperture and the subpixels.

However, the present invention allows for direct deposition without some of the disadvantages of the prior art. A first aspect of the invention provides a deposited material having higher resolution and fidelity for the aperture pattern of the shadow mask, such that only evaporated atoms propagating along a direction substantially perpendicular to the surface of the substrate reach the shadow mask. By enabling the patterning of, the feathering can be significantly reduced.

Another aspect of the invention is that by using a non-metallic material such as silicon nitride for the shadow mask, the shadow mask can be made very thin (≦ 1 micron), thereby significantly reducing the shadowing that occurs in prior art shadow masks. .

Another aspect of the present invention is that by using a shadow mask chuck sized and arranged to counteract the effects of gravity on the shadow mask, the sag of the shadow mask caused by gravity can be reduced or eliminated.

Another aspect of the invention is that a substrate chuck and a shadow mask chuck that does not have a structure protruding above the top surface of the substrate and the shadow mask can mitigate feathering by allowing an extremely small separation or even contact between the substrate and the shadow mask. Is there. In addition, substrate / shadow mask contact can increase their stability during deposition, improve material utilization by reducing waste, enable faster deposition and higher throughput, and enable deposition at lower temperatures.

2 is a schematic diagram of a cross section of a salient feature of a high precision, direct patterned deposition system in accordance with an exemplary embodiment of the present invention. The system 200 includes a vacuum chamber 202, a substrate chuck 204, a source 104, a shadow mask 106, a mask chuck 206, a collimator 208, and a positioning system. 212. System 200 operates to evaporate the desired pattern of material on the substrate surface without the need for subsequent subtractive patterning operations such as photolithography and etching.

System 200 is described herein in connection with depositing a pattern of luminescent material on a glass substrate as part of the manufacture of an AMOLED display. However, after reading this specification, the present invention provides substantially any thin film on any of a wide variety of substrates such as semiconductor substrates ( eg , silicon, silicon carbide, germanium, etc.), ceramic substrates, metal substrates, plastic substrates, and the like. And to form a directly patterned layer of thick (organic or inorganic) material. Further, although the exemplary embodiment is a thermal evaporation system, those skilled in the art will appreciate that after reading this specification, the present invention may relate to virtually any material deposition process, such as e-beam deposition, sputtering, and the like. . In addition, although the illustrated example is a deposition system suitable for use in a planarization process of a single substrate, the present invention also provides for cluster tool processing, track processing, and roll-to-roll processing. It is suitable for use in other manufacturing methods such as processing, reel-to-reel processing and the like. As a result, the invention is suitable for use in a myriad of applications including, but not limited to, packaging applications, IC manufacturing, MEMS manufacturing, nanotechnology device manufacturing, ball-grid array (BGA) manufacturing, and the like. .

In the example shown, the shadow mask 106 is a high precision shadow mask comprising a handle substrate 224 and a membrane 226, which is suspended over a central opening formed in the handle substrate. The membrane 226 includes a through hole pattern 228. The shadow mask 106 includes two major surfaces, namely the front surface 230 and the rear surface 232. Front surface 230 is the top surface of membrane 226 ( ie , the membrane surface farther to handle substrate 224), which defines plane 118. The back surface 232 is the surface of the handle substrate 224 ( ie , the substrate surface far away from the membrane 226). It should be noted that although the shadow mask 106 is a high precision membrane based shadow mask, the mask chuck according to the present invention can be used to hold virtually any type of shadow mask. Preferably, membrane 226 comprises silicon nitride; Other materials may be used without departing from the scope of the present invention. Preferably, membrane 226 has a thickness of less than 1 micron; Other thicknesses may be used for the membrane without departing from the scope of the present invention.

As mentioned above, by using a shadow mask membrane having a thickness of 1 micron or less, the shadowing effect can be reduced during direct deposition as compared to prior art shadow masks.

Vacuum chamber 202 is a conventional pressure vessel that includes a low pressure environment necessary for evaporation of material 116. In the example shown, the vacuum chamber 110 is a standalone device; Without departing from the scope of the present invention it may also be realized as part of a cluster deposition system or track deposition system in which multiple evaporation chambers are arranged in a preceding chain. In some embodiments, the vacuum chamber 110 may be formed of different materials on the substrate 102, such as, for example, multiple light emitting subpixels that emit light in different colors ( eg, red, green, and blue). Several evaporation source / shadow mask combinations are provided that allow the formation of different patterns.

Controller 240 is a conventional instrument controller, among other things, providing control signals 236 and 238 to substrate chuck 204 and mask chuck 206, respectively.

3 illustrates the operation of a method of depositing a patterned material layer directly on a substrate in accordance with an exemplary embodiment. Method 300 herein refers not only to FIGS. 4A, 4B, 5, 6A, 6B, 7A, 7B, 8A, 8B, 9, 10 and 11A-11C. This is described with continued reference to FIG. 2. The method 300 begins with operation 301, where the collimator 208 is mounted within the collimator chuck 210.

The collimator 208 is a mechanically rigid plate that includes a plurality of channels separated by thin walls, as described in more detail below with respect to FIGS. 11A-11C. The collimator 208 is sized and arranged to function as a spatial filter that selectively passes evaporated atoms propagating along a direction that is nearly perpendicular to the plane 108 ( ie , having a very small propagation angle). Thus, the collimator 202 relaxes feathering throughout the substrate 102.

Collimator chuck 210 is an annular clamping mechanism for holding and positioning the collimator relative to shadow mask 106.

In operation 302, the shadow mask 106 is mounted within the mask chuck 206.

The mask chuck 206 is a fixture for holding the shadow mask 106 through the attraction force imparted only on its backside. In the example shown, the mask chuck 206 maintains the shadow mask 106 using electrostatic force. In some embodiments, the mask chuck 206 maintains the shadow mask through different attractive forces, such as forces generated in a vacuum, magnetic forces, and the like. In another embodiment, the mask chuck 206 is a mechanical clamp.

4A and 4B are schematic views illustrating a plane and a cross section, respectively, of a mask chuck according to an exemplary embodiment. The cross section shown in FIG. 4B is taken through the line a-a shown in FIG. 4A. Mask chuck 206 includes frame 402, electrodes 404-1 and 404-2, and pad 406.

Frame 402 is a circular ring of structurally robust electrically insulating material. Frame 402 surrounds opening 408, which is large enough to expose the entirety of through-hole pattern 228. In some embodiments, frame 402 has a shape other than circular, such as square, rectangular, irregular, and the like. In some embodiments, frame 402 comprises an electrically conductive material coated with an electrical insulator.

Electrodes 404-1 and 404-2 are electrically conductive elements formed on the surface of frame 402. The electrodes 404-1 and 404-2 are electrically coupled with the controller 240.

Pad 406 is a plate of structurally rigid electrically insulating material disposed on electrodes 404-1 and 404-2. Each pad 406 includes a mounting surface 410, and the shadow mask is held relative to the mounting surface when the shadow mask 106 is mounted in the mask chuck.

5 is a cross-sectional view of the shadow mask 106 mounted on the mask chuck 206.

The shadow mask 106 is maintained in the mask chuck 206 by the electrostatic force applied between the mounting surface 410 and the back surface 232. The electrostatic force is generated in response to the voltage potential between the electrodes 404-1 and 404-2 generated by the control signal 238. When the back surface 232 is in contact with the mounting surface 410, a sympathetic charge region occurs in the handle substrate 224 as shown. As a result, electrostatic force is selectively imparted between the back surface 232 and the mounting surface 410.

In general, the shadow mask 106 is only supported at its periphery. As a result, shadow masks in the prior art tend to sag down by gravity. In some embodiments, the mask chuck according to the present invention includes one or more features to mitigate or eliminate the sag caused by gravity of the shadow mask when the shadow mask is mounted. As described above, the shadow mask may be deflected by several microns at the center due to the influence of its mass and gravity. This gravity-induced sag causes some important problems that make feathering worse. First, this deflection increases the separation distance between the shadow mask and the substrate at the center of the deposition region, which is typically the center of the shadow mask. As mentioned above, feathering increases with substrate / shadow mask spacing. Second, this deflection causes non-uniform spacing between the substrate and the shadow mask, which causes a change in the degree of feathering that occurs across the substrate surface. This nonuniformity makes it difficult, if not impossible, to compensate for feathering through creative mask layout.

Another aspect of the invention is that the mask chuck can include features to mitigate the sagging of the shadow mask caused by gravity.

In some embodiments, the mask chuck 206 includes some curvature ( eg, upward tilt) that biases the shadow mask upwards to offset the shadow mask sag due to gravity. In some embodiments, a fine support structure can extend across the opening of the mask chuck 206 to support the mask and reduce gravity deflection. This feature is described in more detail below with reference to FIGS. 6A, 6B, 7A, and 7B.

6A and 6B schematically illustrate a cross section of a portion of a mask chuck according to a first alternative embodiment of the invention. The cross section shown in FIG. 6A is taken through line a-a shown in FIG. 4A. Mask chuck 600 includes frame 402, electrodes 404-1 and 404-2, and pad 702.

Pad 602 is similar to pad 406 described above; Each pad 602 has a mounting surface designed to induce tensile strain in or increase tensile strain in the shadow mask when the shadow mask is mounted to the mask chuck. The pad 602 has a mounting surface 604 linearly tapered downward from the inner edge 606 ( ie , the edge close to the opening 408) to the outer edge 608. That is, the mounting surface 604 is, as shown, from point 614 to point 616 ( ie , outside of plane 612 from where the mounting surface meets the inner edge 606 of plane 610). Tapered in the negative z direction to where it meets edge 608. Thus, in embodiments where the inner edge 606 is perpendicular to the plane 610, the inner edge 606 and mounting surface 604 form an interior angle θ that is acute.

When the shadow mask 106 is held within the mask chuck 600, the back surface 232 is pulled to the mounting surface 604, inducing the curvature of the shadow mask to increase the lateral tension at the front surface 230 of the shadow mask. do. As a result, the membrane is pulled more firmly, and the deflection caused by gravity is reduced or eliminated.

6B schematically illustrates a cross section of a portion of a mask chuck in accordance with a second alternative embodiment of the present invention. The cross section shown in FIG. 6B is taken through line a-a shown in FIG. 4A. Mask chuck 618 includes frame 402, electrodes 404-1 and 404-2, and pad 720.

Pad 620 is similar to pad 406 described above; Like pad 602, each pad 620 has a mounting surface designed to induce tensile strain in or increase tensile strain in the shadow mask when the shadow mask is mounted to the mask chuck. The pad 620 has a mounting surface 622 that curves downward from the inner edge 606 to the outer edge 608 ( ie , in the negative z direction as shown). That is, mounting surface 622 is tapered in the negative z direction from point 614 to point 616, as shown.

When the shadow mask 106 is held within the mask chuck 618, the back surface 232 is pulled to the mounting surface 622 to induce the curvature of the shadow mask to increase the lateral tension at the front surface 230 of the shadow mask. do. As a result, the membrane is pulled more firmly, and the deflection caused by gravity is reduced or eliminated. In some embodiments, the amount of additional tension induced in the front face 230 may be controlled by controlling the magnitude of the voltage potential applied to the electrodes 404-1 and 404-2.

After reading this specification, it will be apparent to one skilled in the art that the direction in which the tabbed surfaces 604 and 622 are inclined will be reversed for the deposition system in which the mask is mounted upside down compared to the orientation shown in FIG. will be. Also in this configuration, the substrate chuck 204 will generally need to be designed such that the substrate 102 resides in the opening 408 such that the substrate / shadow mask spacing is less than 10 microns.

7A and 7B schematically illustrate a plane and a cross section, respectively, of a mask chuck according to a third alternative embodiment of the invention. Mask chuck 700 includes mask chuck 206 and support grid 702.

The support grid 702 includes a plate 704 and a support rib 706.

Plate 704 is a rigid plate from which support ribs 706 extend. In some embodiments, plate 704 and support ribs 706 are processed from a solid body of structural material. Suitable materials for use in the plate 704 and support ribs 706 include, but are not limited to, metals, plastics, ceramics, composites, glass, and the like. The plate 704 is designed to mount a frame 402 that locates the support grid 702 in the opening 408 to mechanically mount the membrane 226 when the shadow mask 106 is mounted to the mask chuck 700. Will be supported.

The support ribs 706 are arranged to support the shadow mask 106 in areas that exist between the through holes of the through hole arrangement 228. Typically, the through holes of the shadow mask are arranged in clusters corresponding to different die regions on the substrate. Since these die regions are generally separated by "lanes" intended for removal by a dicing saw, the support ribs 706 are preferably arranged to match the arrangement of these lanes. However, it should be appreciated that any suitable arrangement of support ribs may be used for the support grid 702.

The support grid 702 is formed such that its top surface 708 forms the same plane and defines a plane 710. Plane 710 lies on mounting surface 410 a distance equal to the thickness of frame 224. As a result, when the frame 224 is in contact with the mounting surface 410, the support ribs 706 are in contact with the membrane 226.

In some embodiments, the shadow mask 106 is held upside down in the mask chuck 700 such that the membrane 226 is in contact with the mounting surface 410. In this embodiment, the support grid 702 is designed to fit the opening 408 such that the plane 710 is coplanar with the mounting surface 410. As a result, the membrane 226 is supported by the support grid 702, which is perfectly horizontal in all directions across the opening 408.

In operation 303, the substrate 102 is mounted in the substrate chuck 204.

The substrate chuck 204 is a platen for holding the substrate 102 through an attractive force applied only to its rear surface. In the example shown, the substrate chuck 204 generates electrostatic force to hold the substrate; In some embodiments, the substrate chuck 204 holds the substrate through different attractive forces, such as forces generated in a vacuum, magnetic forces, and the like. For the purposes of this specification, including the appended claims, the term “magnetic force” includes any force generated due to the use of permanent magnets and / or electromagnets. The substrate chuck 204 is described in more detail below with respect to FIGS. 8A and 8B.

In some embodiments, the substrate chuck 204 is sized and arranged to contact the substrate 102 only from the front surface to mitigate interference with material deposition on the other side of the substrate. In some embodiments, the substrate chuck 204 holds the substrate through different means, such as vacuum, mechanical clamps, etc. from both sides of the substrate. In some embodiments, the substrate chuck 204 uses in-situ gap sensors that operate to control the spacing and parallelism between the substrate 102 and the shadow mask 106 using the positioning system 212. Comprise.

In the example shown, the substrate 102 is a glass substrate suitable for use in an Active-Matrix Organic Light Emitting Diode (AMOLED) display. Substrate 102 includes two major surfaces on which display elements are defined, namely back surface 115 and front surface 114. Front side 114 defines plane 108.

8A is a schematic cross-sectional view of a substrate chuck in accordance with an exemplary embodiment. The substrate chuck 204 includes a platen 802 and electrodes 804-1 and 804-2.

Platen 802 is a structurally rigid platform that includes substrate 806 and dielectric layer 808. Each of the substrate 806 and the dielectric layer 808 includes an electrically insulating material such as glass, ceramic, anodized aluminum, a composite material, Bakelite, and the like, so that the electrodes 804-1 and 804-2 are separated from each other. Then, the substrate 102 is electrically insulated from the substrate 102 when mounted on the substrate chuck.

Electrodes 804-1 and 804-2 are electrically conductive elements formed on the surface of substrate 806 and are overcoated by dielectric layer 808 and embedded within platen 802. The electrodes 804-1 and 804-2 are electrically coupled with the controller 240. It should be noted that electrodes 804-1 and 804-2 are shown in simple plates; Indeed, the substrate chuck 204 may have electrodes shaped in any manner, such as interdigitated comb fingers, concentric rings, irregular shapes, and the like.

Dielectric layer 808 is a structurally rigid glass layer disposed over electrodes 804-1 and 804-2 to cause mounting surface 810.

8B schematically illustrates a cross section of the substrate chuck 204 while holding the substrate 102.

To maintain the substrate 102 in the substrate chuck 204, the control signal 236 generates a voltage potential between the electrodes 804-1 and 804-2. When the back surface 115 contacts the mounting surface 810 ( ie , top surface of the dielectric layer 808), sympathetic charge regions occur in the substrate 102 as shown. As a result, electrostatic force is selectively imparted to the rear surface 115, attracting the rear surface to the mounting surface 610.

Although an exemplary embodiment includes a substrate chuck 102 for holding a substrate through electrostatic force, after reading this specification, the substrate is held within the substrate chuck through an attraction force other than electrostatic force, such as force generated in a vacuum, magnetic force, and the like. It will be apparent to those skilled in the art how to identify, manufacture, and use alternative embodiments.

In operation 304, the relative positions of the substrate 102, the source 104, the shadow mask 106 and the collimator 208 are controlled by the positioning system 212.

Positioning system 212 aligns the substrate 102 with the shadow mask 106 by controlling the position of the substrate chuck 204. In some embodiments, the positioning system aligns the shadow mask with the substrate by controlling the position of the mask chuck 206. In some embodiments, the position of the two chucks is controlled to align the substrate and the shadow mask. Operation 304 and positioning system 212 are described in more detail below with respect to FIGS. 1, 2, 9, 10 and 11A-11C.

The positioning system includes three six-axis manipulators and an optical alignment system to control the alignment between the substrate 102 and the shadow mask 106. Each of the six-axis manipulator is operatively connected to each of the substrate chuck 204, the mask chuck 206, and the collimator chuck 210, such that its position along the x-axis, y-axis, and z-axis and the x-axis , control its rotation about each of the y and z axes. In some embodiments, the position of at least one of the mask chuck 206 and the collimator chuck 210 is not controlled by a six-axis positioner. In some embodiments, positioning system 212 also includes a rotation stage for controlling the relative rotational alignment of substrate 102 and shadow mask 106.

In operation 304, the positioning system 212 includes the deposition point R in the deposition region 216 aligned with the aperture 120, the planes 108 and 118 being parallel, and the substrate and shadow mask Position the substrate and the shadow mask so that the spacing S therebetween is as close to zero as possible, preferably within a few microns (eg, 1 to 5 microns). In some embodiments, S is another suitable separation distance. It should be noted that for clarity, the separation distance s is shown larger than the typical one.

One aspect of the invention is that, in some embodiments, neither the substrate chuck 204 nor the mask chuck 206 includes any structural element that projects beyond the respective mounting surface. As a result, the substrate and shadow mask can be aligned with little or no separation between the substrate and the shadow mask to mitigate feathering during deposition. Those skilled in the art will appreciate that in conventional direct deposition systems, the separation between the substrate and the shadow mask should be at least tens or even hundreds of microns.

9 is a schematic illustration of a cross section of a portion of system 100 with substrate 102 and shadow mask 106 aligned for deposition of material 116.

When the substrate and shadow mask are aligned, they collectively define the region 902 between them. Region 902 has the same lateral range L1 as that of front side 114. Region 902 also has the same thickness as the spacing s1 ( ie , the spacing between the substrate and the shadow mask) between plane 108 and plane 118.

Since no portion of the substrate chuck 204 extends beyond the plane 108 into the area 902, there are no obstacles between the substrate and the shadow mask. As a result, the separation distance s1 between the substrate 102 and the shadow mask 106 can be very small (≦ 10 microns). Indeed, if necessary, the substrate and the shadow mask may be in contact with each other. The ability to perform direct patterning with substrate / shadow mask spacing of less than 10 microns provides particularly advantageous advantages of prior art direct patterning deposition systems to embodiments of the present invention, which can significantly reduce or eliminate feathering. Because. In some embodiments, there are no gaps or zero gaps between the substrate and the shadow mask to completely eliminate feathering.

In operation 305, the source 104 generates a vapor column 124. As described in connection with FIG. 1 above, the propagation angle of the evaporated atoms of the vapor column 124 spans a relatively large angular range of −θ m to + θ m. In the prior art, this large angular range exacerbates feathering, which is incident on the lateral and rotational alignments between the substrate 102 and the shadow mask 106, the spacing between them (s), and the shadow mask. It becomes a function of the propagation angle range θp of the evaporated atoms.

However, in the present invention, the range of propagation angles for the evaporated atoms reaching the substrate surface is reduced by placing a spatial filter ( ie, collimator 208) in its path from the source 104 to the shadow mask 106. . Thus, including the collimator 208 in the system 200 significantly reduces feathering during direct deposition.

FIG. 10 schematically illustrates an enlarged view of a pixel region 112 of a substrate 102 and an aperture 120 of a corresponding shadow mask 106. As shown in the figure, for complete fidelity between the aperture 120 and the deposition of the material on the deposition point R, the propagation angle of the evaporated atoms penetrated by the shadow mask 106 ranges from -θa to + θa. It must be within an acceptable range. For purposes of this specification, including the appended claims, the term “acceptable angle range” is defined as the range of propagation angles desired to be penetrated by the shadow mask, which range of angles of −θa to + θa It is in range. Typically, the acceptable angle range is the range of angles that allow material 116 to be deposited only on deposition point R after passing through aperture 120. In some embodiments, the acceptable angular range allows for less than half of the spacing between the nearest points, including a small guard zone around the deposition point. Any evaporated atoms incident on the shadow mask having a propagation angle outside this acceptable angle range will deposit on the surface 114 beyond the lateral range of the deposition point R.

In operation 306, the steam column 124 is filtered by the collimator 208 to generate the steam column 214.

11A is a schematic diagram of a cross-sectional view of a collimator in accordance with an exemplary embodiment. The collimator 208 includes a body 1102 patterned to form a plurality of channels 1104, each channel extending through the thickness of the body 1102.

The main body 1102 is a glass plate suitable for the planarization process. In the example shown, the body 1102 has a thickness of about 25 millimeters (mm); Any actual thickness may be used without departing from the scope of the present invention. In some embodiments, the body 1102 comprises different structurally rigid materials suitable to withstand the temperatures associated with heat and / or e-beam evaporation without significant deformation. Suitable materials for use in the body 1102 include, without limitation, semiconductors ( eg, silicon, silicon carbide, etc.), ceramics ( eg, aluminum, etc.), composite materials ( eg, carbon fibers, etc.), Glass fibers, printed circuit boards, metals, polymers ( eg, polyetheretherketone (PEEK), and the like) and the like.

Channel 1104 may be formed using conventional processing operations such as metal forming, drilling, electron-discharge machining, deep reactive-ion etching (DRIE), and the like. It is a through hole formed in 1102. In the example shown, the channel 1104 has a circular cross section with a diameter of approximately 3 mm. Channel 1104 thus has an aspect ratio of height to width of about 8: 1. Preferably, the aspect ratio of height to width is at least equal to 3: 1. Also for height to width aspect ratios greater than 100: 1, the flow of evaporated atoms through the collimator begins to decrease to undesirable levels; Aspect ratios of height to width in excess of 100: 1 are within the scope of the present invention. In some embodiments, channel 1104 has a cross-sectional shape other than circular ( eg, square, rectangular, hexagonal, octagonal, irregular, etc.).

Formation of channel 1104 creates a plurality of walls 1106 that reside between the channels. Preferably, to enable high throughput, the walls 1106 are formed as thin as possible without sacrificing the structural integrity of the body 1102. In the example shown, wall 506 has an average thickness of about 500 microns; Any actual thickness can be used for the wall 1106.

11B and 11C schematically show plan and cross-sectional views of regions of the collimator 208, respectively. Channels 1106 are arranged in a honeycomb arrangement in which the columns are periodic and adjacent columns are offset half their period from their neighbors. In some embodiments, the channels are arranged in other arrangements, such as two-dimensional periodic, hexagonally packed, random, and the like.

As shown in FIG. 11C, the aspect ratio of the channel 1104 defines a filtered angular range. For purposes of this specification, including the appended claims, the term "filtered angle range" is defined as the range of propagation angles that will pass through collimator 208, which ranges from -θc to + θc. Spans the range. As a result, | θc | Evaporated atoms with larger propagation angle will be blocked by the collimator.

Those skilled in the art will appreciate that the dimensions provided above for the body 1102, the channels 1104 and the walls 1106 are merely exemplary and other dimensions may be used without departing from the scope of the present invention.

In operation 307, aperture 120 passes through the evaporated atoms of vapor column 214 such that the evaporated atoms are deposited on deposition point R in deposition region 216.

In optional operation 308, positioning system 212 imparts motion to collimator 208, thereby improving the uniformity of evaporated atomic density over the lateral range of vapor column 214, thereby Improve deposition uniformity across deposition points on 102. In some embodiments, positioning system 212 operates to impart vibratory movement to collimator 208.

It should be noted that in an exemplary embodiment, the source 104 is substantially a point source for the material 116 because the open area of the crucible is much larger than the area of the substrate 102. Because it is smaller.

In optional operation 309, positioning system 212 improves deposition uniformity by moving source 102 relative to the substrate in the x-y plane.

In some embodiments, source 104 is a linear evaporation source that includes a plurality of nozzles that emit a fan shaped vapor column of vaporized atoms. In some embodiments, positioning system 212 moves the linear source along a direction that is not aligned with its longitudinal axis in the x-y plane to improve the uniformity of the deposited material on substrate 102. In some embodiments, this path is a line that is substantially perpendicular to both the linear arrangement of nozzles and the straight axis 110. In some embodiments, the source is moved along a nonlinear path in the x-y plane.

In some embodiments, source 104 includes a two-dimensional nozzle arrangement, with each nozzle emitting a conical vapor column, such that the plurality of nozzles are vaporized substantially uniformly over an area of the substrate surface. It provides the flow of atoms collectively. In some embodiments, positioning system 212 moves the two-dimensional nozzle arrangement to enable deposition uniformity. In some embodiments, the two-dimensional nozzle arrangement is rotated in plane to enable deposition uniformity.

In some embodiments, source 104 is a two-dimensional planar source that includes a layer of material 116 distributed over the top surface. The source is arranged such that its upper surface is parallel to and opposite the substrate 102. When heated, the material 116 evaporates uniformly over the plane. Exemplary planar deposition sources suitable for use in the embodiments of the present invention are described in Tung, et al ., “OLED Fabrication Using New Planar Deposition Techniques” Int. J. of Photoenergy , Vol. 2014 (18), pp. 1-8 (2014), which is incorporated herein by reference.

In some embodiments, positioning system 212 is moved with source 104 by moving at least one of the substrate / mask combination and the source to improve uniformity in which material 116 is deposited over two-dimensional surface 114 regions. Imparts relative movement between the combination of substrate 102 and shadow mask 106.

The present disclosure teaches only some embodiments according to the present invention, and it is understood that many modifications of the present invention can be readily devised by those skilled in the art after reading the present disclosure and the scope of the present invention should be determined by the following claims. It must be understood.

Claims (55)

A system for depositing a first material on a plurality of deposition points in a deposition region of a substrate, the system comprising:
The plurality of deposition points are arranged in a first arrangement, the substrate comprising a first major surface, and a second major surface comprising the deposition region,
The deposition system is:
A source providing a first plurality of evaporated atoms of the first material, wherein each of the first plurality of evaporated atoms is characterized by a propagation angle in a first direction perpendicular to a first plane defined by the substrate Propagates along a propagation direction built up, wherein a range of propagation angles of the first plurality of evaporated atoms spans a first angle range;
A shadow mask comprising a plurality of through holes arranged in said first arrangement, said shadow mask comprising a third major surface and a fourth major surface comprising said through holes;
A first chuck for holding the substrate, the first chuck sized and arranged to selectively impart a first attractive force on the first major surface;
A second chuck for holding the shadow mask, the second chuck including a frame surrounding a first opening that allows the material to pass through the through hole through the second chuck, the second chuck Sized and arranged to selectively impart a second attractive force on the third major surface;
A collimator comprising a plurality of channels, wherein the collimator is between the source and the shadow mask, each of the plurality of channels passing only evaporated atoms having a propagation angle within a second angle range less than the first angle range. Sized and arranged such that-and;
And a positioning system for controlling the relative position of the first chuck and the second chuck to align the shadow mask with the substrate.
Deposition system. The method of claim 1,
The first material is an organic material
Deposition system. The method of claim 2,
The first material is an organic material operative to emit light
Deposition system. The method of claim 1,
The plurality of deposition points and the plurality of through holes collectively define an acceptable angle range, and the second angle range is less than or equal to the allowable angle range.
Deposition system. The method of claim 1,
Each of the plurality of channels is characterized by an aspect ratio of height to width equal to or greater than approximately 3: 1.
Deposition system. The method of claim 1,
Each of the plurality of channels is characterized by an aspect ratio of height to width of at least 8: 1.
Deposition system. The method of claim 1,
The positioning system is operative to impart relative motion between the substrate and the collimator.
Deposition system. The method of claim 1,
The first chuck, the second chuck, and the positioning system collectively enable alignment of the shadow mask with the substrate such that the separation distance between the substrate and the shadow mask is less than about 10 microns.
Deposition system. The method of claim 8,
The first chuck, the second chuck, and the positioning system collectively enable alignment of the substrate and the shadow mask such that the separation distance between the substrate and the shadow mask is greater than 0 microns and less than about 10 microns.
Deposition system. The method of claim 1,
The first chuck, the second chuck, and the positioning system collectively enable alignment of the substrate and the shadow mask such that the separation distance between the substrate and the shadow mask is within a range from about 2 microns to about 5 microns. doing
Deposition system. The method of claim 1,
The second attraction force is an electrostatic force
Deposition system. The method of claim 1,
The second attraction force is selected from the group consisting of a force and a magnetic force generated in a vacuum
Deposition system. The method of claim 1,
The second chuck is sized and arranged to relieve sag caused by gravity of the shadow mask.
Deposition system. The method of claim 13,
The frame has a cross section defining a mounting surface extending between a first edge close to the first opening and a second edge farther from the first opening, the mounting surface retaining the shadow mask on the second chuck. The mounting surface and the first edge meet at a point in a first plane, the mounting surface and the second edge meet at a point in a second plane, and the first plane Closer to the substrate than the second plane when the shadow mask and the substrate are aligned
Deposition system. The method of claim 14,
The mounting surface is nonlinear
Deposition system. The method of claim 1,
The second chuck further includes a support grid in the first opening, the support grid being sized and arranged to mitigate the sag caused by gravity of the shadow mask.
Deposition system. The method of claim 1,
Each of the first attraction force and the second attraction force is an electrostatic force
Deposition system. The method of claim 1,
The shadow mask includes silicon nitride
Deposition system. The method of claim 1,
The shadow mask has a thickness of less than 1 micron
Deposition system. A system for depositing a first material on a plurality of deposition points in a deposition region of a substrate, the system comprising:
The plurality of deposition points are arranged in a first arrangement, the substrate comprising a first major surface, and a second major surface having a first lateral range,
The deposition system is:
A source operative to provide a first plurality of evaporated atoms—each evaporated atoms of the first plurality of evaporated atoms move along a direction of propagation defining a propagation angle such that the first plurality of evaporated atoms Characterized by a first plurality of propagation angles over a first angular range;
A shadow mask comprising a plurality of through holes arranged in said first arrangement, said shadow mask comprising a third major surface and a fourth major surface comprising said through holes, said shadow mask and said plurality of deposition points collectively Define an acceptable angle range less than the first angle range;
A first chuck for holding the substrate;
A second chuck for holding the shadow mask, the second chuck comprising a frame surrounding a first opening that allows the material to pass through the through hole through the second chuck, the shadow mask and the When the substrate is aligned, the shadow mask and the substrate collectively define a first region, the first region having (1) a second lateral range equal to or greater than the first lateral range, (2 A thickness equal to the separation distance between the substrate and the shadow mask, (3) excluding the first chuck and the second chuck, the first chuck and the second chuck being sized such that the thickness is less than 10 microns. And arranged—and;
A collimator positioned between the source and the shadow mask,
The collimator includes a plurality of channels for selectively passing a second plurality of evaporated atoms, wherein the first plurality of evaporated atoms includes the second plurality of evaporated atoms, each of the plurality of channels The channel has a height-to-width aspect ratio that defines a filtered angular range that is less than or equal to the acceptable angular range, and wherein the second plurality of evaporated atoms is characterized by a second plurality of propagation angles that are less than or equal to the filtered angular range. Built
Deposition system. The method of claim 20,
The substrate defines a first plane and a first direction perpendicular to the first plane, the source includes a plurality of nozzles for emitting the plurality of evaporated atoms, the plurality of nozzles in the first plane Arranged in a second arrangement having a first length along a second direction in a second plane substantially parallel to the source, wherein the source is movable along a path in the second plane, the path aligned with the second direction Not
Deposition system. The method of claim 20,
The deposition region has a first region in the first plane, the source comprising a first nozzle for emitting the plurality of evaporated atoms, the source being a second plane substantially parallel to the first plane Movable within
Deposition system. The method of claim 20,
And a positioning system operative to impart relative motion between the substrate and the collimator.
Deposition system. The method of claim 20,
The first chuck and the second chuck are sized and arranged such that the thickness is 0 micron so that the substrate and the shadow mask are in contact.
Deposition system. The method of claim 20,
The first and second chucks are sized and arranged such that the thickness is greater than 0 microns and less than 10 microns.
Deposition system. The method of claim 20,
The second chuck is operative to impart a first attraction force only on the third major surface
Deposition system. The method of claim 26,
The first attraction force is an electrostatic force
Deposition system. The method of claim 26,
The first attraction force is selected from the group consisting of a force and a magnetic force generated in a vacuum
Deposition system. The method of claim 26,
The first chuck is operative to impart a second attraction force only on the first major surface.
Deposition system. The method of claim 29,
Each of the first attraction force and the second attraction force is an electrostatic force
Deposition system. The method of claim 20,
The second chuck is sized and arranged to mitigate the sag caused by gravity of the shadow mask when a second shadow mask is held at the second chuck.
Deposition system. The method of claim 31, wherein
The second chuck is sized and arranged to mitigate the sag caused by gravity of the shadow mask by inducing tensile stress on the fourth major surface.
Deposition system. The method of claim 31, wherein
The second chuck is sized and arranged to produce curvature of the shadow mask.
Deposition system. The method of claim 31, wherein
The second chuck includes a support grid located within the first opening, the support grid being sized and arranged to physically support the shadow mask.
Deposition system. The method of claim 20,
The shadow mask includes silicon nitride
Deposition system. The method of claim 20,
The shadow mask has a thickness of less than 1 micron
Deposition system. A method of depositing a first material on a plurality of deposition points arranged in a first array on a substrate, the method comprising:
The substrate comprises a first major surface and a second major surface having a first lateral range, the second major surface comprising the first region,
The method is:
Providing a shadow mask comprising a plurality of through holes, the shadow mask comprising a third major surface and a fourth major surface comprising the through holes;
Maintaining the substrate in a first chuck that selectively imparts a first attractive force on the first major surface;
Maintaining the shadow mask in a second chuck that selectively imparts a second attractive force on the third major surface, the second chuck through which the evaporated valences of the material pass through the plurality of through holes through the second chuck. To pass through-and;
Positioning the substrate and the shadow mask such that the second major surface and the fourth major surface are separated by a distance of 10 microns or less;
Receiving a first plurality of evaporated atoms in a collimator positioned between a source and the shadow mask, wherein the first plurality of evaporated atoms are characterized by a first propagation angle range;
Selectively passing a second plurality of evaporated atoms through the collimator through the shadow mask, wherein the first plurality of evaporated atoms comprises the second plurality of evaporated atoms and wherein the second plurality of evaporated atoms The atom is characterized by a second propagation angle range narrower than the first propagation angle range;
Allowing at least some of the second plurality of evaporated atoms to be deposited on the substrate through the second chuck and the plurality of through holes.
Way. The method of claim 37, wherein
Providing the collimator comprising a plurality of channels, each of the plurality of channels having a height-to-width aspect ratio that determines the second propagation angle range.
Way. The method of claim 38,
The aspect ratio of the height to width is based on an acceptable angular range, which is defined by the substrate and the shadow mask.
Way. The method of claim 39,
The aspect ratio of the height to width defines a filtered angle range that is less than or equal to the allowable angle range.
Way. The method of claim 37, wherein
Producing the first plurality of evaporated atoms in a source;
Further comprising moving the source relative to the substrate.
Way. 42. The method of claim 41 wherein
Providing the source as a linear nozzle arrangement
Way. 42. The method of claim 41 wherein
Further comprising providing the source as a two-dimensional nozzle arrangement
Way. The method of claim 37, wherein
Further imparting relative movement between the collimator and the substrate
Way. The method of claim 37, wherein
The substrate and the shadow mask are aligned such that the second major surface and the fourth major surface are spaced apart by a distance greater than 0 microns and less than 10 microns.
Way. The method of claim 37, wherein
The substrate and the shadow mask are aligned such that the second major surface and the fourth major surface are spaced apart by a distance in the range of about 2 microns to about 5 microns.
Way. The method of claim 37, wherein
Generating the second attractive force as an electrostatic force
Way. The method of claim 47,
Generating the first attractive force as an electrostatic force
Way. The method of claim 37, wherein
Alleviating the sag caused by gravity of the shadow mask
Way. The method of claim 49,
The gravity induced deflection is mitigated by inducing tensile strain on the fourth major surface.
Way. 51. The method of claim 50 wherein
The tensile strain is induced on the fourth major surface by creating a curvature of the shadow mask.
Way. The method of claim 49,
The deflection caused by gravity is mitigated by mechanically supporting the shadow mask in the area of the shadow mask including the through hole.
Way. The method of claim 52, wherein
Further comprising providing the second chuck,
The second chuck is:
A frame surrounding a first opening operative to allow particles comprising the material to pass through the through hole through the second chuck;
A support grid located within the first opening, the support grid being sized and arranged to physically support the shadow mask.
Way. The method of claim 37, wherein
The shadow mask includes silicon nitride
Deposition system. The method of claim 37, wherein
The shadow mask has a thickness of less than 1 micron
Deposition system.

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