The present disclosure generally relates to the development of variable deposition profiles for augmented/virtual reality, meta-surfaces, or other optical hardware. More specifically, the disclosure relates to masks and masking techniques to produce variable deposition profiles.
In various applications, such as augmented reality, virtual reality, holographics, and waveguides, one or more lithography processes are often used to achieve a target deposition profile. For example, forming a complex deposition profile having different depths across the surface of a substrate has conventionally been performed via a series of lithographic steps, such as gray-tone lithography, used in combination with subtractive manufacturing and wet etch-dry etch combinations. However, this process is time-consuming and complex, for example, due to dependence on etch chemistry and/or selectivity, which adds considerable costs to devices fabricated using the process.
Accordingly, improved methods and related equipment are needed for forming complex target deposition profiles on substrates.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended as an aid in determining the scope of the claimed subject matter.
In some embodiments, a method may include positioning a mask over a substrate, wherein the mask has a planar surface separated from a top surface of the substrate by a mask distance, and wherein a mask opening is provided through the planar surface. The method may further include positioning a mask element across the mask opening, the mask element including one or more solid portions and one or more openings, and depositing, through the mask opening, a deposition material onto the substrate, wherein the deposition material has a variable profile as a result of the one or more solid portions and the one or more openings.
In some embodiments, a mask for variable deposition profiles may include a planar plate with a mask opening, a mask element with one or more solid portions and a set of openings, wherein the mask element extends across at least a portion of the mask opening. The mask element is arranged to block deposition of a deposition material onto one or more portions of a substrate to produce a target deposition profile of the deposition material.
In some embodiments, a system may include a substrate within a plasma chamber, and a mask positioned over the substrate, wherein the mask includes a planar plate with a mask opening, and a mask element with one or more solid portions and a set of openings, wherein the mask element extends across at least a portion of the mask opening, and wherein the mask element is arranged to control deposition of a deposition material onto one or more portions of the substrate to produce a target deposition profile of the deposition material.
The accompanying drawings illustrate exemplary approaches of the disclosure, including the practical application of the principles thereof, as follows:
The drawings are not necessarily to scale. The drawings are merely representations, not intended to portray specific parameters of the disclosure. The drawings are intended to depict exemplary embodiments of the disclosure, and therefore are not be considered as limiting in scope. In the drawings, like numbering represents like elements.
Furthermore, certain elements in some of the figures may be omitted, or illustrated not-to-scale, for illustrative clarity. The cross-sectional views may be in the form of “slices”, or “near-sighted” cross-sectional views, omitting certain background lines otherwise visible in a “true” cross-sectional view, for illustrative clarity. Furthermore, for clarity, some reference numbers may be omitted in certain drawings.
Apparatuses, systems, and methods in accordance with the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, where various embodiments are shown. The apparatuses, systems, methods may be embodied in many different forms and are not to be construed as being limited to the embodiments set forth herein. Instead, these embodiments are provided so the disclosure will be thorough and complete, and will fully convey the scope of the apparatuses, systems, and methods to those skilled in the art.
In one or more embodiments of the present disclosure, target deposition profiles and patterns may be obtained by varying one or more of deposition process parameters (e.g., pressure, gas ratios, chemistry), plasma sources (e.g., an inductively coupled plasma (ICP) or a capacitively coupled plasma), masks or mask elements (e.g., variable mask shapes, Moiré stacking, mask rotation, pitch changes and height from substrate), etc. In many embodiments, a plasma gradient is generated using a shadow mask, which causes the plasma density to vary due to the shadowing. In several embodiments, one or more masks may be utilized in the stitching of multiple patterns. Oftentimes the target deposition profiles may be utilized for augmented reality, virtual reality, holographic, and/or waveguide applications, such as for electromagnetic metasurfaces. Embodiments herein are not limited in this context, however.
In one or more embodiments of the present disclosure, components of operating environment 100 may be utilized to efficiently obtain target deposition profiles atop the substrate 102. For instance, one or more characteristics of the substrate 102, mask 104, plasma chamber 108, reacting gas 110, gas inlet(s) 118, deposition plasma 112, pedestal 114, and pump 116 may be tuned to efficiently obtain a target deposition profile. In some embodiments, as will be discussed in more detail below, the mask 104 may control or alter the deposition of material onto the substrate 102 to facilitate creation of a target deposition profile of material on the substrate 102. It will be appreciated that the position the mask 104 may be modified relative to the substrate 102. For example, one or more of a target height, angle, rotation, pitch, and slope with respect to the substrate 102 may be configured as desired. In some embodiments, the mask 104 may comprise a metal or metal alloy, such as aluminum. Embodiments herein are not limited in this context.
As shown in
As shown by deposit 220 in
As used herein, the variable deposition profile 222 of the deposit 220 may refer to the shape, thickness, and/or height of the deposit 220 atop the substrate 202. In some embodiments, the variable deposition profile 222 may also refer to characteristics of the deposit 220 including, but not limited to, electromagnetic properties, material, index of refraction, weight, concentration, density, volume, transparency, translucency, cross-section, layers, and the like.
Deposit 220 may include a material that can be applied by a PECVD process. In various embodiments, deposit 220 may comprise a dielectric thin film, such as one or more of silicon mononitride (SiN), silicon carbonitride (SiCN), silicon oxynitride (SiON), silicon dioxide (SiO2), amorphous silicon (a-Si), polycrystalline silicon (poly-Si), metal oxides, metals, and various alloys. In some embodiments, deposit 220 may comprise a plurality of materials and/or layers.
As shown in
In another embodiments, as shown in
The mask 304 may further include an opening 317, wherein the deposition material 320 may generally pass freely through the opening 317 to the substrate 302. A first interior portion 327A may include a first plurality of openings 335 extending through a first plate 336, while a second interior portion 327B may include a second plurality of openings 337 through a second plate 338. In some embodiments, a size (e.g., diameter) of the first and second plurality of openings 335, 337 may be the same or different. As demonstrated in portion ‘C’, larger-sized openings 335 generally allow more of the deposition material 320 to pass through the first plate 336 and reach the substrate 302. As demonstrated in portion ‘E’, smaller-sized openings 337 generally allow less of the deposition material 320 to pass through the second plate 338 and reach the substrate 302. The smaller-sized openings 337 provide additional control over the resolution of the profile 333. In other words, the smaller the diameter of the openings, the higher the resolution.
It will be appreciated that mask 304 represents one non-limiting example. For example, although the first and second plurality of openings 335, 337 are shown as being circular, any variety of opening shape/profile may be possible. Furthermore, in various embodiments, different target deposition profiles may be obtained through intricate shape stitching in the mask 304. For example, the mask 304 may include a protruding structure or feature (not shown), such as a flap, covering, overhang, tab, etc., which covers or partially covers any one of opening 317, openings 335, and openings 337, and which extends away from the mask 304. Although non-limiting, the feature may include a fixed end coupled to the mask 304 and a free end angling away from the mask 304. As a result, plasma of the deposition material 320, which may have a uniform density above the mask 304, may have a gradient density in an area beneath the feature and above a processing area of the substrate 302.
It will be appreciated that the feature of the mask 304 may take on a variety of shapes and configurations in various embodiments. By varying the shape, configuration, and/or distance of the feature from the mask 304, as well as by varying a width, height and/or size of the corresponding opening, the plasma density gradient in the area beneath the feature and above the processing area may also be varied.
Masks 404-1, 404-2 may comprise a planar surface with one or more mask openings 429. In some embodiments, masks 404-1, 404-2 may include one or more layers (e.g., layer 438 comprising mask element(s) 430) covering one or more portions of the mask opening(s) 429. In other embodiments, masks 404-1, 404-2 may not include any layers covering one or more portions of the mask opening 429. In the illustrated embodiments, the mask opening 429 is rectangular. In other embodiments, the mask opening 429 may have any geometric shape, such as circular, triangular, and the like, or a combination thereof. As shown in
When no mask is present over the substrate, deposition profiles 433-0, 435-0, 437-0, which have a relatively uniform thickness, may result. The deposition profiles 433-0, 435-0, 437-0 may be referred to as having one deposit component. The relatively uniform thickness may be the thickest in the middle and the thinnest at the extents.
Mask 404-1 (
Mask 404-2 can result in deposition profiles 433-2, 435-2, 437-2, which have a central hump and additional humps at the extents with a greater thickness than the central hump. The deposition profiles 433-2, 435-2, 437-2 may be referred to as having five deposit portions with a first deposit portion comprising the hump proximate the −100 mm extent of the charts, a second deposit portion comprising the zero thickness portion proximate the −50 mm portion of the charts, a third deposit portion comprising the central hump proximate the 0 mm portion of the charts, a fourth deposit portion comprising the zero thickness portion proximate the 50 mm portion of the charts, and a fifth deposit portion comprising the hump proximate the 100 mm extent of the charts. In various embodiments, the central hump (e.g., third deposit portion) may result from layer 438 covering a portion of the mask opening 429 of mask 404-2, the additional humps (e.g., first and fifth deposit portion) may result from being beyond the extents of the planar surface of the mask 404-2, and the zero thickness portions (e.g., second and fourth deposit portions) may result from the solid planar surface of the mask 404-2. Additionally, the reduced thickness of the central hump (e.g., third deposit portion) and the individual crests along a top thereof may result from shaped openings 431 of layer 438 of shaped openings 431 of the mask element(s) 430.
In some embodiments, mask layer/element stitching may be utilized to obtain Moiré patterned deposits. Further, mask elements, or layers, may comprise one or more meshes of various sizes. For example, micron-sized meshes and/or stacked masks (or stacked layers) may be used to obtain Moiré patterned deposits with finer feature control. In
Compound layers may also be stacked and translated and/or rotated with other layers or compound layers to produce layer sets. For example, in
Furthermore, in some embodiments, layer sets may also be stacked to form layer stacks, such as for finer feature control. Referring to
Accordingly, stacking copies of the same pattern on top of one another can provide finer feature control. One of ordinary skill in the art will appreciate that distinctions between layers, compound layers, layer sets, and layer stacks herein are for clarity of description, but more generally the terms may be used interchangeably. For example, a layer may comprise or refer to a compound layer, a layer set, or a layer stack.
In many embodiments, a deposit, or deposition profile, may include one or more deposit components. In many such embodiments, the one or more deposit components may be discrete or continuous. In
An electromagnetic metasurface may include a thin film materials with sub-wavelength thickness to allow for exotic optical/electromagnetic properties. More generally, metasurfaces may modulate behaviors of electromagnetic waves through specific boundary conditions. In some embodiments, metasurfaces may be the same as or similar to a two-dimensional version of a three-dimensional metamaterial. Metasurfaces may be structured with scaled patterns of constant/variable height (see e.g.,
Target deposition profile 642-1 on substrate 602-2 illustrates a first exemplary deposition profile that may be obtained through mask stitching and/or controlling other aspects of the deposition process. Target deposition profile 642-1 incorporates a variety of discrete deposition components arranged to form a metasurface. Target deposition profile 642-2 illustrates a second exemplary deposition profile for a metasurface that may be obtained through mask stitching and/or controlling other aspects of the deposition process.
Turning to
In some embodiments, a second mask element is positioned across the mask opening, wherein the second mask element includes one or more second openings. In some embodiments, the mask element and the second mask element are stacked relative to one another. In some embodiments, the mask element and the second mask element are rotated/translated relative to one another to limit deposition of the first material onto the first target portion of the substrate. In some embodiments, the method includes varying a diameter between the one or more openings of the mask element and the one or more second openings of the second mask element. In some embodiments, the mask element and the second mask element may be positioned between the planar surface of the mask and the top surface of the substrate.
At block 706, the method 700 may include depositing, through the mask opening, a deposition material onto the substrate, wherein the deposition material has a variable profile as a result of the one or more solid portions and the one or more openings.
At block 708, the method 700 may optionally include etching the first material to form plurality of fins and a plurality of trenches. In some embodiments, the etch is a vertical etch. In some embodiments, the etch is an angled ion (e.g., ribbon beam) delivered at a non-zero angle of inclination relative to a perpendicular to a top surface of the substrate. Once formed, the plurality of fins and plurality of trenches may be part of an optical grating with slanted fins/structures. Embodiments herein are not limited in this context.
For the sake of convenience and clarity, terms such as “top,” “bottom,” “upper,” “lower,” “vertical,” “horizontal,” “lateral,” and “longitudinal” will be used herein to describe the relative placement and orientation of components and their constituent parts as appearing in the figures. The terminology will include the words specifically mentioned, derivatives thereof, and words of similar import.
As used herein, an element or operation recited in the singular and proceeded with the word “a” or “an” is to be understood as including plural elements or operations, until such exclusion is explicitly recited. Furthermore, references to “one embodiment” of the present disclosure are not intended as limiting. Additional embodiments may also incorporate the recited features.
Furthermore, the terms “substantial” or “substantially,” as well as the terms “approximate” or “approximately,” can be used interchangeably in some embodiments, and can be described using any relative measures acceptable by one of ordinary skill in the art. For example, these terms can serve as a comparison to a reference parameter, to indicate a deviation capable of providing the intended function. Although non-limiting, the deviation from the reference parameter can be, for example, in an amount of less than 1%, less than 3%, less than 5%, less than 10%, less than 15%, less than 20%, and so on.
Still furthermore, one of ordinary skill will understand when an element such as a layer, region, or substrate is referred to as being formed on, deposited on, or disposed “on,” “over” or “atop” another element, the element can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on,” “directly over” or “directly atop” another element, no intervening elements are present.
In various embodiments, design tools can be provided and configured to create datasets used to obtain target deposition profiles. For example, data sets can be created to determine mask and/or process characteristics to obtain a target deposition profile. In some such examples, the data sets may be created based on historical data from previous depositions. Such design tools can include a collection of one or more modules and can also be comprised of hardware, software or a combination thereof. Thus, for example, a tool can be a collection of one or more software modules, hardware modules, software/hardware modules or any combination or permutation thereof. As another example, a tool can be a computing device or other appliance running software, or implemented in hardware.
As used herein, a module might be implemented utilizing any form of hardware, software, or a combination thereof. For example, one or more processors, controllers, ASICs, PLAs, logical components, software routines or other mechanisms might be implemented to make up a module. In implementation, the various modules of the present disclosure might be implemented as discrete modules or the functions and features described can be shared in part or in total among one or more modules. In other words, as would be apparent to one of ordinary skill in the art after reading the description, the various features and functionality of the present disclosure may be implemented in any given application. Furthermore, the various features and functionality can be implemented in one or more separate or shared modules in various combinations and permutations. Although various features or elements of functionality may be individually described or claimed as separate modules, one of ordinary skill in the art will understand these features and functionality can be shared among one or more common software and hardware elements.
By utilizing the embodiments of the present disclosure, target deposition profiles and patterns may be efficiently obtained by combining (e.g., via stacking, rotating, translating, displacing) masks and/or mask elements relative to one or more other components, such as masks, mask elements, and substrates. Oftentimes this may include one or more of selecting the shapes and patterns utilized in one or more layers of a mask, the orientation of a layer relative to one or more other layers, and the spacing of the mask relative to a substrate to apply the target deposition profile. A first technical advantage of the masks and mask elements of the present embodiments includes improved manufacturing efficiency by eliminating more time consuming, costly, and difficult processes, such as gray-tone lithography, to achieve target deposition profiles.
Further, a second technical advantage of the present embodiments includes applicability to a wide range of chemistries, such as to efficiently accommodate a variety of etching methods. In many embodiments, utilization of an additive line-of-sight deposition process based on plasma gradients may allow a wide variety of dielectric films, such as SiN, SiCN, SiON, SiO2, amorphous-Si, and metals, to be used in deposition profiles. Further, additive line-of-sight deposition processes can remove complexity of subtractive methods, such as where final profiles are dependent on the etching chemistry, selectivity, and are only valid for a specific material or combination of materials.
The present disclosure is not to be limited in scope by the specific embodiments of the present disclosure. Indeed, other various embodiments of and modifications to the present disclosure, in addition to those of the present disclosure, will be apparent to those of ordinary skill in the art from the foregoing description and accompanying drawings. Thus, such other embodiments and modifications are intended to fall within the scope of the present disclosure. Those of ordinary skill in the art will recognize the usefulness is not limited thereto and the present disclosure may be beneficially implemented in any number of environments for any number of purposes. Thus, the claims set forth below are to be construed in view of the full breadth and spirit of the present disclosure as of the present disclosure.