Methods and apparatus for photolithographically patterning materials in integrated circuit packages

Abstract

To provide systems, an apparatus, articles of manufacture, and methods for photolithographically patterning materials in integrated circuit packages.SOLUTION: A photolithography mask 212 includes a transparent substrate, and an opaque material supported by the transparent substrate. The opaque material covers a first area of the transparent substrate. The photolithography mask further includes an optical filter supported by the transparent substrate. The optical filter covers a second area of the transparent substrate. The second area is distinct from the first area. Both the opaque material and the optical material are separated apart from a third area of the transparent substrate.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates generally to semiconductor device manufacturing, and more specifically, to methods and apparatus for photolithographically patterning materials in integrated circuit packages. [Background technology]

[0002] Semiconductor device manufacturing involves a variety of processes to manufacture integrated circuits or chips. Many processes involved in semiconductor device manufacturing involve the use of photolithography. Photolithography involves directing light onto a layer of a light-sensitive material (e.g., photoresist, sometimes simply referred to as resist) in a controlled manner to generate a pattern in the layer of material to retain some portions of the layer of material and remove other portions. Depending on the particular material and technique involved, the retained portions may correspond to areas of the layer of material that were exposed to the light, and the removed portions correspond to areas that were not exposed to the light. However, in other situations, the retained portions may correspond to areas that were not exposed to the light, and the removed portions correspond to areas that were exposed to the light. Often, the exposure of light onto the photoresist is controlled by using a photolithography mask (e.g., photomask or simply mask) between the light source and the photoresist. [Brief description of the drawings]

[0003] [Figure 1] 1 illustrates an exemplary integrated circuit (IC) package constructed in accordance with the teachings disclosed herein.

[0004] [Diagram 2] 2 illustrates an exemplary system for photolithographically patterning material in the IC package of FIG. 1.

[0005] [Diagram 3] 1 illustrates i-line light being exposed onto solder resist after passing through a photomask.

[0006] [Figure 4] 4 illustrates h-line light being exposed onto the same solder resist as in FIG. 3 after passing through the same photomask as in FIG. 3.

[0007] [Diagram 5] 1 shows the photomask aligned over the solder resist after being exposed to i-line light through the photomask.

[0008] [Figure 6] Another photomask is shown aligned over another solder resist after exposure to h-line light through the photomask.

[0009] [Figure 7] 1 is a cross-sectional side view of an exemplary photomask constructed in accordance with the teachings disclosed herein.

[0010] [Figure 8] FIG. 8 is a bottom view of the example photomask of FIG.

[0011] [Figure 9] 7 and 8 illustrate an exemplary photomask used to pattern the solder resist of FIGS. 3 and 4 with the filtered light of FIG.

[0012] [Figure 10] 1 illustrates an exemplary photomask aligned over solder resist after being simultaneously exposed to both i-line and h-line light through the exemplary photomask.

[0013] [Figure 11] 1 illustrates different exemplary photomasks constructed in accordance with the teachings disclosed herein. [Figure 12] 1 illustrates different exemplary photomasks constructed in accordance with the teachings disclosed herein. [Figure 13]1 illustrates different exemplary photomasks constructed in accordance with the teachings disclosed herein. [Figure 14] 1 illustrates different exemplary photomasks constructed in accordance with the teachings disclosed herein. [Figure 15] 1 illustrates different exemplary photomasks constructed in accordance with the teachings disclosed herein. [Figure 16] 1 illustrates different exemplary photomasks constructed in accordance with the teachings disclosed herein. [Figure 17] 1 illustrates different exemplary photomasks constructed in accordance with the teachings disclosed herein. [Figure 18] 1 illustrates different exemplary photomasks constructed in accordance with the teachings disclosed herein. [Figure 19] 1 illustrates different exemplary photomasks constructed in accordance with the teachings disclosed herein.

[0014] [Figure 20] 1 illustrates an exemplary stage in a manufacturing process for adding distinct areas of opaque material to a transparent substrate for a photomask. [Figure 21] 1 illustrates an exemplary stage in a manufacturing process for adding distinct areas of opaque material to a transparent substrate for a photomask. [Figure 22] 1 illustrates an exemplary stage in a manufacturing process for adding distinct areas of opaque material to a transparent substrate for a photomask. [Diagram 23] 1 illustrates an exemplary stage in a manufacturing process for adding distinct areas of opaque material to a transparent substrate for a photomask. [Figure 24] 1 illustrates an exemplary stage in a manufacturing process for adding distinct areas of opaque material to a transparent substrate for a photomask.

[0015] [Diagram 25]25 illustrates an exemplary stage in the manufacturing process for adding an optical filter adjacent to the discrete region of opaque material shown in FIG. 24. [Figure 26] 25 illustrates an exemplary stage in the manufacturing process for adding an optical filter adjacent to the discrete region of opaque material shown in FIG. 24. [Figure 27] 25 illustrates an exemplary stage in the manufacturing process for adding an optical filter adjacent to the discrete region of opaque material shown in FIG. 24.

[0016] [Figure 28] 25 illustrates an alternative exemplary stage in the manufacturing process of adding an optical filter adjacent to a discrete region of opaque material, such as the opaque material shown in FIG. 24. [Figure 29] 25 illustrates an alternative exemplary stage in the manufacturing process of adding an optical filter adjacent to a discrete region of opaque material, such as the opaque material shown in FIG. 24. [Diagram 30] 25 illustrates an alternative exemplary stage in the manufacturing process of adding an optical filter adjacent to a discrete region of opaque material, such as the opaque material shown in FIG. 24. [Diagram 31] 25 illustrates an alternative exemplary stage in the manufacturing process of adding an optical filter adjacent to a discrete region of opaque material, such as the opaque material shown in FIG. 24. [Diagram 32] 25 illustrates an alternative exemplary stage in the manufacturing process of adding an optical filter adjacent to a discrete region of opaque material, such as the opaque material shown in FIG. 24.

[0017] [Diagram 33] 1 is a flow chart illustrating an example method of manufacturing any of the example photomasks disclosed herein. [Diagram 34] 1 is a flow chart illustrating an example method of manufacturing any of the example photomasks disclosed herein. [Diagram 35]1 is a flow chart illustrating an example method of manufacturing any of the example photomasks disclosed herein.

[0018] Generally, the same reference numbers are used throughout the drawings and the accompanying written description to refer to the same or similar parts. The figures are not necessarily to scale. Alternatively, thicknesses of layers or regions may be exaggerated in the drawings. While layers and regions having clear lines and boundaries are shown in the figures, some or all of these lines and / or boundaries may be idealized. In reality, the boundaries and / or lines may be unobservable, blended, and / or irregular. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] FIG. 1 illustrates an exemplary integrated circuit (IC) package 100 constructed in accordance with the teachings disclosed herein. In the illustrated example, the IC package 100 is electrically coupled to a circuit board 102 via an array of bumps or balls 104 (e.g., a ball grid array (BGA)) that protrude from a mounting surface (e.g., an outer surface) 106 of the package 100. In this example, the bumps 104 are electrically coupled to corresponding contacts or landing pads 108 on an opposing mounting surface (e.g., a top surface) 110 of the circuit board 102. In this example, the landing pads 108 are flush with the top surface 110 of the circuit board 102. In other examples, the landing pads 108 are recessed relative to the top surface 110. In other examples, the landing pads 108 protrude beyond the top surface 110. In this example, the package 100 includes a semiconductor (e.g., silicon) die 112 mounted to a package substrate 114 and surrounded by a package lid or mold compound 116. 1 includes a single die 112, in other examples, package 100 may have multiple dies (e.g., two or more positioned side-by-side and / or two or more stacked on top of each other on package substrate 114). Die 112 may provide any suitable type of functionality (e.g., data processing, memory capacity, etc.).

[0020] As shown in the illustrated example, the die 112 is electrically and mechanically coupled to the package substrate 114 via an array of corresponding bumps or balls 118. The electrical connection between the die 112 and the package substrate 114 (e.g., bumps 118) is sometimes referred to as a first level interconnect 120. In contrast, the electrical connection between the IC package 100 and the circuit board 102 (e.g., bumps 104) is sometimes referred to as a second level interconnect 122. In some examples, when multiple dies are included in the package 100, a die may be stacked on top of one or more other dies and / or interposers. In such examples, a die may be coupled to an underlying die and / or interposer via a first set of first level interconnects, and the underlying die and / or interposer may be connected to the package substrate 114 via a separate set of first level interconnects associated with the underlying die and / or interposer. Thus, as used herein, a first level interconnect refers to a bump or ball, or other type of interconnect between the die and the package substrate, or between the die and the underlying die and / or interposer.

[0021] As shown in FIG. 1 , the bumps 118 of the first level interconnect 120 are physically connected and electrically coupled to contact pads 124 on an inner surface 126 of the substrate 114. For illustrative purposes, the contact pads 124 are shown to be flush with the inner surface 126 of the substrate 114. However, in some examples, the contact pads 124 are inlaid with respect to the inner surface 126. Specifically, in some such examples, the inner surface 126 is defined by a solder resist 202 (shown in FIG. 2 ) and includes a number of openings that expose corresponding ones of the plurality of contact pads 124. The contact pads 124 along the inner surface 126 of the package substrate 114 are electrically coupled to the bumps 104 on the bottom (outer) surface 106 of the substrate 114 (e.g., the surface opposite the inner surface 126) via internal interconnects 128 within the substrate 114. As a result, there is a complete signal path between the bumps 118 of the die 112 and the landing pads 108 on the circuit board 102, passing through the contact pads 124, the interconnects 128, and the bumps 104 therebetween. The interconnects 128 are shown as simple lines for illustrative purposes in the depicted example of FIG. 1. However, the internal interconnects 128 may be implemented by traces or electrical wiring in different metal layers in the board 114 separated by layers of dielectric material. The traces in the different metal layers are electrically coupled by metal vias that extend through the layers of dielectric material.

[0022] Figure 2 illustrates an example system 200 for photolithographically patterning material in the IC package 100 of Figure 1. For purposes of illustration, Figure 2 is described with respect to patterning solder resist 202 on the interior surface 126 of the package substrate 114 of Figure 1. However, the example methods and apparatus disclosed herein may be suitably adapted to photolithographically pattern material in other layers within the package substrate 114. Additionally, the teachings disclosed herein may also be used to photolithographically pattern material in the die 112.

[0023] At the manufacturing stage depicted in Figure 2, the contact pads 124 of the package substrate 114 of Figure 1 are covered with solder resist. Thus, the photolithography process illustrated in Figure 2 is to pattern the solder resist 202 to define openings that expose the contact pads 124 and allow electrical and mechanical coupling with the bumps 118 on the die 112 as shown in Figure 1.

[0024] The exemplary system 200 of FIG. 2 includes a light source 204 that generates light 206 (e.g., unfiltered light) having a particular spectral profile. In this example, the light source 204 is a high pressure mercury lamp. The spectrum of light generated by the mercury lamp includes several spikes of relatively high intensity light at particular wavelengths. Different ones of the spikes of high intensity light from the mercury lamp are referred to herein as different lines, including i-line light, h-line light, and g-line light. As used herein, i-line light is light having a wavelength of about 365 nanometers (nm), h-line light is light having a wavelength of about 405 nm, and g-line light is light having a wavelength of about 435 nm.

[0025] As shown in the illustrated example, light 206 (e.g., unfiltered light) emitted from light source 204 passes through optical filter 208 (also referred to as a cut filter) to generate filtered light 210. Many known lithography techniques employ optical filters that filter or cut all light except a single specific ray (e.g., all except i-line light, or all except h-line light). Unlike these existing approaches, optical filter 208 of FIG. 2 is constructed to allow the passage of both i-line and h-line light, but filter or cut g-line light and other wavelengths of light.

[0026] As shown in the illustrated example, the filtered light 210 passes through a photomask 212 (or simply mask) and a projection lens 214 to generate masked light 216 that is illuminated onto the solder resist 202 of the package substrate 114. Typically, a photomask includes a transparent base or substrate. In some examples, the transparent substrate is a solid piece of glass (e.g., a glass pane, panel, or sheet). In some examples, the transparent (e.g., glass) substrate includes at least one of: aluminosilicate, borosilicate, aluminoborosilicate, silica, and / or fused silica. In some examples, the transparent (e.g., glass) substrate includes one or more additives including: aluminum oxide (Al2O3), boron trioxide (BO3), magnesia oxide (MgO), calcium oxide (CaO), stoichiometric silicon oxide (SrO), barium oxide (BaO), tin oxide (SnO2), nickel alloy (Na2O), potassium oxide (KO), phosphorus trioxide (PO3), zirconium dioxide (ZrO2), lithium oxide (Li2O), titanium (Ti), and / or zinc (Zn). In some examples, the transparent (e.g., glass) substrate includes silicon or oxygen. In some examples, the transparent (e.g., glass) substrate includes silicon, oxygen, and / or one or more of aluminum, boron, magnesium, calcium, barium, tin, sodium, potassium, strontium, phosphorus, zirconium, lithium, titanium, and / or zinc. In some examples, the transparent (e.g., glass) substrate comprises at least 23 weight percent silicon and at least 26 weight percent oxygen. In some examples, the transparent (e.g., glass) substrate is a layer of glass comprising silicon, oxygen, and aluminum. In some examples, the transparent (e.g., glass) substrate comprises at least 23 weight percent silicon, at least 26 weight percent oxygen, and at least 5 weight percent aluminum. In some examples, the transparent (e.g., glass) substrate is an amorphous solid glass layer.

[0027] In addition to a transparent (e.g., glass) substrate, the photomask typically includes an opaque material that partially covers the transparent substrate in areas that correspond to the pattern to be transferred to the solder resist 202. That is, the areas that correspond to the opaque material block the filtered light 210 from reaching the solder resist 202, while the areas without the opaque material allow the light to pass through and illuminate the solder resist 202. The solder resist is a photosensitive material, such that the portions of the solder resist 202 that are exposed to the masked light 216 will change properties in response to the light. Specifically, in some instances, the solder resist 202 that is exposed to the light will harden, such that when a developer is applied to the solder resist 202, the portions that remain relatively soft (e.g., the portions that were not exposed to the light) will be removed, while the hardened portions will remain. In this manner, the pattern defined by the opaque areas on the photomask 212 will be transferred to the solder resist 202.

[0028] Known photomasks typically modify light in a binary manner, either by blocking the light (e.g., by an opaque material) or by allowing the light to pass (e.g., where there is no opaque material). Unlike known photomasks, the example photomask 212 of FIG. 2 is not binary, but selectively allows certain wavelengths of light in some regions and other wavelengths in other regions. More specifically, as labeled in FIG. 2, the masked light 216 in the illustrated example includes i-line light from filtered light 210, where the h-line light has been partially filtered. That is, in this example, the photomask 212 filters or blocks the h-line light in some regions, but allows the i-line light to pass through these same regions. However, there are other regions where both i-line light and h-line light (e.g., all of the i-line and h-line light) are allowed to pass through the mask 212. Additionally, in some examples, the photomask 212 includes regions blocked by opaque material that does not allow either the i-line light or the h-line light to pass through. Thus, the photomask 212 in the illustrated example includes a binary first region that allows most (e.g., all) light to pass through, and a second region that blocks the light, but the light that passes through the first region is further divided into multiple subregions that allow different wavelengths of light to pass through (e.g., some subregions allow both i-line and h-line light, while other subregions allow only i-line light).

[0029] Although FIG. 2 is shown and described as partially filtering h-line light but allowing i-line light to pass through the photomask 212 at certain locations, in other examples, the h-line light is allowed wherever there is no opaque material, and the i-line light is selectively filtered at certain locations where the h-line light is allowed to pass. Furthermore, in some examples, both the i-line light and the h-line light may be filtered (e.g., blocked) in certain areas where other lines of light are allowed to pass. Furthermore, while the examples shown in FIG. 2 focus on i-line light and h-line light, the teachings disclosed herein may be applied to any other wavelengths of light. For example, in some examples, the optical filter 208 is modified to allow g-line light (or any other suitable wavelengths of light) to pass and be included in the filtered light 210. In some such examples, the photomask 212 is constructed to selectively filter the g-line light at locations where other wavelengths of light are still allowed to pass. Additionally, in some examples, a different type of light source 204 may be used that emits different wavelengths of light (e.g., having a different spectral profile) than the mercury lamp described above. In such examples, the photomask 212, as disclosed herein, may selectively filter certain wavelengths of light from passing, while allowing other wavelengths of light. In some examples, the filtering function of the photomask 212 may perform the function of the optical filter 208 by completely filtering certain wavelengths of light while still allowing other wavelengths of light to pass. As such, in some such examples, the optical filter 208 is omitted.

[0030] While the teachings disclosed herein may be applied to any wavelength of light, the example shown in FIG. 2 in which the filtered light 210 incident on the photomask 212 includes i-line light and h-line light will be described in detail for purposes of illustration. I-line light and h-line light are two common wavelengths of light used in photolithography, each with advantages and disadvantages as illustrated with reference to FIGS. 3 to 6. FIG. 3 illustrates i-line light 302 exposed on the solder resist 304 after passing through a photomask 306. FIG. 4 illustrates h-line light 402 exposed on the same solder resist 304 as in FIG. 3 after passing through the same photomask 306 as in FIG. 3. For purposes of illustration, the i-line light 302 is represented by a lighter shade, a short dashed line, and an arrow with an open chevron head. In contrast, the h-line light 402 is represented by a darker shade, a long dashed line, and an arrow with a closed chevron head.

[0031] As shown in Figures 3 and 4, the photomask 306 includes a transparent base or substrate 308 that supports an opaque material 310. In many known photomasks, the transparent substrate 308 corresponds to a pane of glass (e.g., a glass panel, a glass sheet), and the opaque material 310 is composed of chrome. The opaque material 310, as its name suggests, prevents or impedes light 302, 402 incident thereon from passing through the photomask 306. However, for purposes of simplicity, the light 302, 402 incident on the opaque material 310 is not shown in Figures 3 and 4.

[0032] As shown by a comparison of Figures 3 and 4, there are two main differences between the i-line light 302 (Figure 3) and the h-line light 402 (Figure 4). The first difference is the depth to which each wavelength of light penetrates into the solder resist 304. Specifically, the i-line light 302 has a shorter wavelength than the h-line light 402 (e.g., 365 nm compared to 405 nm for the h-line light). Due to the shorter wavelength, the i-line light 302 reaches a first depth 312 that is shallower than the second depth 404 reached by the h-line light 402. The i-line light 302 is limited to a relatively shallow depth due to the absorption and / or scattering of the relatively short wavelength light by the solder resist 304. The second difference between the i-line light 302 and the h-line light 402, also based on different wavelengths, is the diffraction angle of the light at the edge of the opaque material 310. As shown in FIGS. 2 and 3, the i-line light 302 is diffracted at a first angle 314 that is less than the second angle 406 encountered by the h-line light 402 .

[0033] The two differences between the i-line light 302 and the h-line light 402 noted above represent advantages and disadvantages of each wavelength of light over the other. In particular, the shallow reach (e.g., relatively shallow depth) of the i-line light 302 represents a limit to the depth to which the solder resist 304 can be patterned. In contrast, the h-line light 402 extends to a deeper depth 404 for more reliable patterning of deeper openings in the solder resist 304. Thus, in terms of exposure depth, the h-line light 402 is generally preferred over the i-line light 302. On the other hand, the smaller diffraction angle 314 of the i-line light 302 is advantageous over the larger diffraction angle 406 of the h-line light 402 because the smaller angle 314 results in higher resolution in transferring the pattern on the mask (e.g., the pattern of the opaque material 310 on the photomask 306) to the solder resist 304. The higher resolution means that it is possible to create finer features and / or position multiple openings closer together in the solder resist 304 exposed to the i-line light 302 than is possible using the h-line light 402. In essence, there is a trade-off between the two light beams 302, 402, each having advantages over the other. The importance of these advantages (and / or corresponding disadvantages) is illustrated with reference to Figures 5 and 6.

[0034] Figure 5 shows a photomask 502 aligned over a solder resist 504 after exposure to an i-line light (e.g., i-line light 302 depicted in Figure 3) through the mask 502. Figure 6 shows another photomask 602 aligned over another solder resist 604 after exposure to an h-line light (e.g., h-line light 402 depicted in Figure 4) through the mask 602. As shown, the photomasks 502, 602 in each of Figures 5 and 6 include similar transparent substrates 506, 606 supporting first and second regions of opaque material 508, 510, 608, 610, respectively. The regions of opaque material 508, 510, 608, 610 are aligned with and define the size and shape of corresponding openings 512, 514, 612, 614 in the solder resist 504, 604 that were created through a photolithography process to expose or reveal underlying contact pads 516, 518, 616, 618 (e.g., similar to contact pads 124 at the base of solder resist 202 shown in FIG. 2). Specifically, the solder resist 504, 604 is selectively exposed to light (e.g., either an i-line light as in FIG. 5 or an h-line light as in FIG. 6) that passes through the photomask 502, 602 between the regions of the opaque material 508, 510, 608, 610. The portions of the solder resist 504, 604 that are exposed to the light respond to the light by hardening compared to the portions that were not exposed to the light. As a result, when developer is applied to the solder resist 504, 604, the uncured portions (e.g., portions not exposed to light) are removed, while the cured portions (e.g., portions exposed to light) remain. In other words, the openings 512, 514, 612, 614 correspond to the portions of the solder resist 504, 604 that were not exposed to light. Thus, the difference in shape of the openings 512, 514, 612, 614 between Figures 5 and 6 is based on the effect of using different wavelengths of light (e.g., either i-line light (Figure 5) or h-line light (Figure 6)).

[0035] 5 and 6, the first opening 512, 612 (left side of the figure) is a solder mask limited (SMD) opening because the innermost dimension 520, 620 of the first opening 512, 612 in the solder resist 504, 604 corresponds to a critical dimension associated with the extent to which the underlying contact pad 516, 616 is exposed. In contrast, the second opening 514, 614 (right side of the figure) is a solder mask non-limited (NSMD) opening because the innermost dimension 522, 622 of the second opening 514, 614 is wider than the associated contact pad 518, 618 (and thus does not define a critical dimension corresponding to the dimension of the contact pad 518, 618).

[0036] In Figures 5 and 6, the photomasks 502, 602 are constructed such that the innermost dimensions 520, 620 of the first openings 512, 612 are the same and the innermost dimensions 522, 622 of the second openings 514, 614 are the same. This is achieved by designing the areas of opaque material 508, 510, 608, 610 with different dimensions 524, 526, 624, 626, as between Figures 5 and 6. Specifically, the dimensions 524, 526 of the opaque material 508, 510 in Figure 5 are smaller than the dimensions 624, 626 of the opaque material 608, 610 in Figure 6. The dimensions 524, 526 of the opaque materials 508, 510 in Figure 5 can be smaller than the corresponding dimensions 624, 626 in Figure 6 and still produce the same innermost dimensions 520, 522, 620, 622 due to the different angles of diffraction 314, 406 of the different wavelengths of light associated with i-line light (Figure 5) and h-line light (Figure 6). In particular, the angles of diffraction of light correspond to the wall angles 528, 628 of each opening 512, 514, 612, 614 in Figures 5 and 6. That is, due to the smaller diffraction angle 314 of the i-line light 302 (used in FIG. 5), the difference between the innermost dimensions 520, 522 of the openings 512, 514 in FIG. 5 and the uppermost (e.g., top) dimensions at the rims of the openings 512, 514 in FIG. 5 (corresponding to the dimensions 524, 526 of the opaque materials 508, 510) is less than the difference between the innermost and uppermost (e.g., top) dimensions of the openings 612, 614 in FIG. 6. As a result, the opaque materials 508, 510 on the photomask 502 in FIG. 5 can be smaller while still achieving the same critical dimensions of the SMD openings, thereby allowing multiple openings to be made close together (e.g., with higher resolution).

[0037] Although i-line light provides higher resolution for smaller and / or closer features (e.g., openings) than h-line light, the disadvantages of i-line light become clear with reference to the NSMD openings 514, 614 (on the right) of FIGS. 5 and 6. As explained above, i-line light cannot penetrate deep into the solder resist 504. As a result, only the upper portion of the solder resist 504 is exposed to light and hardened, while the solder resist material at the deeper depth remains soft (unhardened). As a result, when developer is applied to remove the unhardened solder resist below the exposure depth, the developer may begin to erode or remove the solder resist material directly below the hardened solder resist material. As a result, the developer may create an undercut 530 below the protruding inflection point 532 (e.g., overhang or outcrop) on the sidewall of the second opening 514 in FIG. 5. The protruding inflection point 532 is generally located at the depth 312 reached by the i-line light 302 shown in Figure 3. The NSMD opening in Figure 6 (e.g., second opening 614) is also defined by an undercut 630 below the protruding inflection point 632 on the sidewall of the opening 614. However, the undercut 630 in Figure 6 is much smaller than the undercut 530 in Figure 5 because the h-line light (used in Figure 6) reaches much deeper into the solder resist 604 and hardens the solder resist material to a greater depth (e.g., below inflection point 632), resulting in less solder resist being removed by the developer below inflection point 632. Importantly, the smaller undercut 630 in FIG. 6 results in a larger area 634 of solder resist 604 remaining between the contact pad 618 and the adjacent contact pad 616 in the corresponding NSMD opening 614 than the remaining area 534 of solder resist 504 between the contact pads 516, 518 in FIG. 5.The larger coverage 634 of the solder resist 604 between the contact pads 616, 618 reduces the likelihood of shorts occurring and / or allows the NSMD opening (e.g., the second opening 614 in FIG. 6) to be positioned closer to adjacent contact pads and / or other electrically conductive components.

[0038] The exemplary photomasks disclosed herein allow for the benefits of both i-line light (which has higher resolution patterns allowing for smaller / closer features) and h-line light (which reaches deeper into the photoresist material reducing the degree of any undercutting). Moreover, the examples disclosed herein capture both of these benefits during a single exposure process. That is, both i-line light and h-line light are simultaneously applied to the photoresist being processed (e.g., solder resist 202, 304, 504, 604 of Figures 2-6). This is made possible by adding optical filters to multiple regions of the photomask to block, cut, or filter certain wavelengths of light in those regions, while still allowing other wavelengths in those regions. However, in other regions, the optical filters are omitted to allow the wavelengths blocked in the first region due to the optical filters. Moreover, the exemplary photomask also includes regions of opaque material through which light does not pass.

[0039] 7 is a cross-sectional side view of an exemplary photomask 700 constructed in accordance with the teachings disclosed herein. The exemplary photomask 700 includes a transparent base or substrate 702 (e.g., a glass panel, pane, sheet) that supports an opaque material 704 similar to the photomasks 306, 502, 602 shown in FIGS. 3 through 6. In some examples, the opaque material 704 is chrome. However, any other opaque material may additionally or alternatively be used.

[0040] Unlike the photomasks 306, 502, 602 of Figures 3-6, the transparent substrate 702 of the exemplary photomask 700 of Figure 7 also supports an optical filter 706. As shown in the illustrated example, the optical filter 706 extends over (e.g., extends across) the opaque material 704 such that the opaque material 704 is between the transparent substrate 702 and the optical filter 706. Furthermore, in the illustrated example, the optical filter 706 extends along a side or edge 708 of the opaque material, encasing or surrounding the opaque material against the surface of the transparent substrate 702. Thus, in some examples, both the opaque material 704 and the optical filter 706 contact the same surface of the transparent substrate 702 such that the opaque material 704 and the optical filter 706 are adjacent to one another along the surface of the substrate 702.

[0041] 8 is a bottom view of the exemplary photomask 700 of FIG. 7. Thus, in FIG. 8, both the opaque material 704 and the optical filter 706 are visible through the transparent substrate 702. In this example, the opaque material 704 covers a first region 802 of the transparent substrate 702, and the optical filter 706 covers a second region 804 of the transparent substrate 702. As shown in FIG. 8, the first region 802 comprises a circle having a first diameter, and the second region comprises a circle (e.g., an annular ring) having a second diameter larger than the first diameter. In this example, the first region 802 is disposed in the center of the second region 804 such that the second region surrounds the first region (e.g., the optical filter 706 surrounds the opaque material 704). In some examples, the second region 804 (associated with the optical filter 706) does not completely surround the first region 802 (associated with the opaque material 704), but instead abuts and / or extends along a portion of the first region 802. Although the first and second regions 802, 804 are shown to have circular shapes suitable for creating round openings in the underlying photoresist (e.g., openings 512, 514, 612, 614 in FIGS. 5 and 6), one or both of the regions may have any other suitable shape. For example, in some examples, the first and / or second regions 802, 804 correspond to elongated lines or strips that may be implemented to pattern elongated trenches in the photoresist. Furthermore, although only one region of the opaque material 704 and one region of the optical filter 706 are shown, any suitable number of regions on the transparent substrate 702 may include one or both of the opaque material 704 and the optical filter 706.

[0042] In addition to the first and second regions 802, 804, the exemplary transparent substrate 702 includes a third region 806 that is not covered by the opaque material 704 and is not covered by the optical filter 706. More wavelengths of light can pass through the transparent substrate 702 than can pass through the optical filter 706, and more wavelengths of light can pass through the optical filter 706 than can pass through the opaque material 704. In some examples, the opaque material 704 does not allow any wavelengths of light to pass through (because it is opaque), but allows all wavelengths of light to pass through the transparent substrate 702 (because it is transparent). However, only certain wavelengths can pass through the optical filter 706, while other wavelengths are filtered or blocked by the optical filter. Specifically, in this example, the transparent substrate 702 allows both i-line and h-line light to pass, and the optical filter 706 allows the i-line light to pass but filters the h-line light. In other examples, different wavelengths of light are filtered by the optical filter 706.

[0043] In some examples, the optical filter 706 is an absorptive filter that filters or cuts selected wavelengths of light by absorbing the light while allowing other wavelengths to pass. Absorptive filters achieve these optical filter properties by being colored with dyes selected based on the wavelengths of light they absorb and / or transmit. Such filters can be made from any suitable material (e.g., glass, polymer, etc.). In other examples, the optical filter 706 is an interference filter (e.g., a dichroic filter) that filters or cuts selected wavelengths from a light source by reflecting those wavelengths while allowing other wavelengths to pass. Interference filters are implemented with multiple thin film layers made of different dielectric and / or metallic materials with different refractive indices that generate interference for selected wavelengths resulting in a filtering function. The particular materials used in the interference filter and / or the design and thickness of the layers depend on the particular wavelengths that are to be filtered and allowed to pass through the filter.

[0044] Because the opaque material 704 blocks the passage of light, the opaque material 704 is an exemplary means for blocking the passage of light. Because the optical filter 706 filters light (e.g., blocks some but not all wavelengths of light), the optical filter 706 is an exemplary means for filtering light. Because the transparent substrate 702 supports (e.g., holds) both the opaque material 704 and the optical filter 706, the transparent substrate 702 is an exemplary means for adjacent to the means for blocking and supporting the means for filtering.

[0045] FIG. 9 illustrates the exemplary photomask 700 of FIGS. 7 and 8 used to pattern the solder resist 304 of FIGS. 3 and 4 with the filtered light 216 of FIG. 2. As explained above, the filtered light 216 includes both the i-line light 302 and the h-line light 402 shown and described in connection with FIGS. 3 and 4. Thus, FIG. 9 is similar to FIGS. 3 and 4, except that both wavelengths of light are applied to the mask 700 simultaneously. As explained above in connection with FIGS. 3 and 4, for illustrative purposes, the i-line light 302 is represented by a light shading, short dashed lines, and an arrow with an open chevron head. In contrast, the h-line light 402 is represented by a darker shading, long dashed lines, and an arrow with a closed chevron head. The areas where both wavelengths shine are represented by a darker shading. A first region 902 in FIG. 9 corresponds to a first region 802 of the transparent substrate 702 covered by the opaque material 704 as shown in FIG. 8. As described above and depicted in FIG. 9, no light passes through the opaque material 704. For purposes of clarity and simplicity, light incident on the opaque material 704 (e.g., as described above) is not shown in FIG. 9. The second region 904 (surrounding the first region 902) corresponds to the second region 804 of the transparent substrate 702 that is covered by the optical filter 706 as shown in FIG. 8. As described above and depicted in FIG. 9, the optical filter 706 allows the i-line light 302 to pass through but blocks or filters (either by absorption or reflection / interference) the h-line light 402. Finally, the third region 906 (surrounding the second region 904) corresponds to the uncovered third region 806 of the transparent substrate 702 as shown in FIG. 8. As described above and depicted in FIG. 9, both the i-line light 302 and the h-line light 402 can pass through the transparent substrate 702 in the third region 904.

[0046] Because the optical filter 706 allows the i-line light 302 to pass through, the i-line light 302 passes through the photomask 700 of FIG. 9 in substantially the same manner as if the optical filter were omitted (as in FIG. 3). That is, the i-line light 302 still extends a first depth 312 into the solder resist 304, and the i-line light 302 still diffracts the same diffraction angle 314 as described above in connection with FIG. 3. Furthermore, because the optical filter 706 prevents the h-line light 402 from passing through, the h-line light 402 passes through the photomask 700 of FIG. 9 in substantially the same manner as if the optical filter were omitted and the opaque material 704 extended to the extent of the optical filter 706. That is, the h-line light 402 still extends a second depth 404 into the solder resist 304, and the h-line light 402 still diffracts the same diffraction angle 406 as described above in connection with FIG. 4. However, the origin of diffraction of the h-line light 402 is shifted outward (to the outer edge of the optical filter 706) compared to the origin of diffraction of the i-line light 302 (at the outer edge of the opaque material 704). In this example, the amount of this shift (e.g., the amount that the optical filter 706 extends beyond the boundary, edge, or perimeter of the opaque material 704) is defined such that the closest dimension 908 between the diffracted portions of the h-line light 402 on opposite sides of the optical filter 706 is approximately the same as the closest dimension 910 between the diffracted portions of the i-line light 302 on opposite sides of the opaque material 704. As a result, as shown in Figure 10, exposures with both lights can be performed simultaneously to achieve the advantages of both wavelengths of light discussed above in connection with Figures 5 and 6.

[0047] FIG. 10 illustrates an exemplary photomask 1000 aligned over solder resist 1004 after being simultaneously exposed to both i-line light 302 and h-line light 402 (as depicted in FIGS. 3 and 4) through the exemplary mask 1000. The exemplary photomask 1000 of FIG. 10 is constructed similarly to the photomask 700 of FIG. 9 with a transparent substrate 1006 supporting first and second regions of opaque material 1008, 1010 and corresponding optical filters 1012, 1014, respectively. In this example, the opaque material 1008, 1010 is shaped to similar dimensions as the opaque material 508, 510 of FIG. 5. That is, both first regions of the opaque material 508, 1008 in FIGS. 5 and 10 have the same dimension 524, and both second regions of the opaque material 510, 1010 in FIGS. 5 and 10 have the same dimension 526. Further, in this example, the optical filters 1012, 1014 are shaped to similar dimensions as the opaque materials 608, 610 in Figure 6. That is, both the first opaque material 608 in Figure 6 and the first optical filter 1012 in Figure 10 have the same dimension 624, and both the second opaque material 610 in Figure 6 and the second optical filter 1014 in Figure 10 have the same dimension 626.

[0048] The opaque materials 1008, 1010 and optical filters 1012, 1014 of Figure 10 constructed with the dimensions outlined above effectively combine the exposure results of the i-line light 302 depicted in Figure 5 with the exposure results of the h-line light 402 depicted in Figure 6. In particular, the SMD opening 1016 (left side of Figure 10) has the same innermost dimension 520 as the first opening 512 of Figure 5, and the narrow top (top) dimension at the rim of the opening 1016 corresponds to the dimension 524 of the opaque material 1008. Thus, the higher resolution (of smaller and / or closer features) achieved by the i-line light 302 is achieved. Additionally, the NSMD opening 1018 (right side of FIG. 10 ) is defined by a sidewall having a first undercut 1020 between first and second protruding inflection points 1022, 1024, and a second undercut 1026 below the second (lower) inflection point 1024. In this example, the first (upper) inflection point 1022 is provided by the i-line light 302, similar to the protruding inflection point 532 of FIG. 5 . Additionally, the first undercut 1020 of FIG. 10 is similar to the undercut 530 occurring below the corresponding inflection point 532 of FIG. 5 . However, because the second inflection point 1022 is provided by the h-line light 402, similar to the protruding inflection point 632 of FIG. 6 , the first undercut 1020 does not extend as far in the illustrated example of FIG. 10 compared to the undercut 530 of FIG. 5 . 5. Thus, the second undercut 1026 below the second inflection point 1024 is similar to the undercut 630 of FIG. 6. As a result, the solder resist 1004 extends between the contact pads 1030, 1032 by the same extent 634 as the solder resist 604 of FIG. 6, thereby reducing the possibility of shorting and / or allowing the contact pads to be placed closer together, as described above in connection with FIG. 6. Furthermore, exposure of the i-line light 302 at the top of the solder resist 1004 at a location corresponding to the outer edge of the opaque material 1010 results in an uppermost (e.g., top) dimension at the rim of the opening 1018 being the same dimension 526 as the opaque material 1010, which is the same dimension 526 as the rim of the opening 514 of FIG. 5.As a result, the top dimension of the opening 514 is smaller than if only h-line light were used (as shown in FIG. 6), thereby allowing smaller (higher resolution) features to be positioned closer together.

[0049] The exemplary photomasks 700, 1000 of FIGS. 7 to 10 have been described in detail. However, many other implementations are possible. In particular, FIGS. 11 to 19 illustrate different exemplary photomasks constructed in accordance with the teachings disclosed herein. For example, FIG. 11 illustrates an exemplary photomask 1100 in which two regions of opaque material 1102 are supported on a transparent substrate 1104, only one of which is surrounded by and / or otherwise adjacent to an optical filter 1106, while the other region of opaque material 1102 is spaced apart from any optical filter 1106. In other words, in some instances, the optical filter 1106 is not necessarily included in association with all regions of opaque material 1102 on the photomask 1100. Similarly, as shown in the exemplary photomask 1200 of FIG. 12, the opaque material 1102 is not necessarily included in association with all regions associated with the optical filter 1106. Specifically, as shown in Figure 12, photomask 1200 includes an optical filter 1106 (on the right) that is spaced apart from any opaque material 1102. Furthermore, in some examples, multiple regions of opaque material 1102 may be associated with, adjacent to, covered by, and / or in contact with a single (e.g., integral) optical filter 1106. For example, the exemplary photomask 1300 of Figure 13 includes a single optical filter 1106 that extends continuously between and / or across two adjacent regions of opaque material 1102.

[0050] In the aforementioned examples, the optical filter 1106 extends over the opaque material 1102 such that the optical filter 1106 (combined with the transparent substrate 1104) surrounds and / or encases the opaque material 1102. However, in some examples, the optical filter 1106 may be spaced apart from the top surface of the opaque material 1102 (e.g., the surface facing away from the transparent substrate 1104), as shown in the illustrated example of FIG. 14. Specifically, the exemplary photomask 1400 of FIG. 14 includes an optical filter 1106 that is constrained to be laterally adjacent to an outer edge and / or periphery of the opaque material 1102. In some examples, the optical filter 1106 partially (but not completely) covers the corresponding surface of the opaque material 1102 facing away from the transparent substrate 1104. In the illustrated example of FIG. 14, the optical filter 1106 has a thickness that is approximately equal to the thickness of the opaque material 1102. However, the example photomask 1500 of FIG. 15 includes an optical filter 1106 having a thickness greater than the thickness of the opaque material 1102. In other examples, the optical filter 1106 has a thickness less than the thickness of the opaque material 1102. In some examples, the thickness of the optical filter 1106 and / or the opaque material 1102 may vary among different locations on the transparent substrate 1104. In some examples, the thickness of the optical filter 1106 is determined by the intended filtering properties of the optical filter 1106. For example, if the optical filter 1106 is implemented as an absorptive filter, the optical filter 1106 may be designed to be thick enough to adequately absorb the relevant wavelengths to be filtered during exposure. Similarly, if the optical filter 1106 is implemented as an interference filter, the optical filter 1106 may be designed with a thickness defined by the number of thin film layers (and their associated thicknesses) to generate an interference effect that results in the relevant wavelengths being filtered during exposure.

[0051] In some examples, the stacked relationship of the transparent substrate 1104, the opaque material 1102, and the optical filter 1106 may vary. For example, Figure 16 illustrates another example photomask 1600 in which the optical filter 1106 is between the transparent substrate 1104 and the opaque material 1102. Additionally, Figure 17 illustrates another example photomask 1700 in which the opaque material 1102 and the optical filter 1106 are on opposing sides of the transparent substrate 1104 (e.g., the transparent substrate 1104 is between the opaque material 1102 and the optical filter 1106).

[0052] In some examples, multiple types of optical filters may be employed on the same transparent substrate to selectively filter different wavelengths of light. For example, FIG. 18 illustrates another example photomask 1800 in which a first region of opaque material 1102 (on the right) is associated with (e.g., covered by) a first optical filter 1106 that filters a first wavelength of light (e.g., h-line light). The example photomask 1800 of FIG. 18 further includes a second region of opaque material 1102 (on the left) that is associated with (e.g., covered by) a second optical filter 1106 that filters a second wavelength of light different from the first wavelength of light (e.g., i-line light). Additionally or alternatively, in some examples, a separate optical filter extends across the surface of the transparent substrate 1104 to filter certain wavelengths across that surface, while still allowing others to be selectively passed or filtered based on other optical filters. In particular, Figure 19 illustrates another exemplary photomask 1900 that is identical to the photomask 1800 of Figure 18, except that the third optical filter 1902 extends continuously across both the first and second optical filters 1106, 1802 and across the exposed portion of the transparent substrate 1104 in the gap between the first and second optical filters 1106, 1802. In some instances, the third optical filter 1902 may function similarly to the optical filter 208 of Figure 2 to filter wavelengths of light that are never intended to reach the underlying substrate being lithographically processed. Thus, in some such instances, the optical filter 208 of Figure 2 may be omitted.

[0053] The above-mentioned examples of photomasks 700, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900 in Figures 7 to 19 teach or suggest different features. Although each of the exemplary photomasks 700, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900 disclosed above has specific features, it should be understood that a specific feature of one example need not be used exclusively in that example. Instead, any of the features described above and / or depicted in the drawings can be combined with any of the examples in addition to or instead of any of the other features of these examples. Features of one example are not mutually exclusive with features of another example. Instead, the scope of the present disclosure encompasses any combination of any of the features.

[0054] 20 through 24 illustrate exemplary stages in a manufacturing process for adding distinct regions of opaque material to a transparent substrate (e.g., glass panel, pane, sheet). FIG. 20 represents a manufacturing stage after depositing a layer of opaque material 2002 on a transparent substrate 2004, and after depositing a layer of photosensitive material (e.g., photoresist) 2006 on the layer of opaque material 2002. FIG. 21 represents selective exposure of photoresist 2006 to light 2102 (e.g., by a laser). In some examples, the portions of photoresist 2006 exposed to light 2102 are the portions that are removed. FIG. 22 represents removal (e.g., by a development process) of the portions of photoresist 2006 exposed to light 2102, thereby exposing the underlying portions of opaque material 2002. FIG. 23 represents removal (e.g., by etching) of the exposed portions of opaque material 2002. 24 depicts the removal (e.g., by stripping) of the remaining portions of photoresist 2006, thereby revealing the final distinct areas of opaque material 2002. In some examples, the distinct areas of opaque material 2002 correspond to opaque material 704 of example photomask 700 of FIGS.

[0055] 25-27 illustrate exemplary stages in a manufacturing process that adds an optical filter adjacent to the distinct regions of opaque material 2002 shown in FIG. 24. That is, FIGS. 25-27 are a continuation of the manufacturing process depicted in FIGS. 20-24. FIG. 25 illustrates a transparent substrate 2004 and the deposition (e.g., by vapor deposition (e.g., chemical vapor deposition (CVD), physical vapor deposition (PVD)) and / or any other suitable vapor deposition technique) of a layer of material 2502 for the optical filter across the distinct regions of opaque material 2002. In this example, the layer of material 2502 is a mixture of a light absorbing material and a photosensitive material. The light absorbing material can be any suitable material capable of absorbing the particular wavelength of light to be filtered or cut. For example, in some examples, a light absorbing material is selected that absorbs h-line light (e.g., by being dyed a suitable color). FIG. 26 illustrates selective exposure of the layer of material 2502 to light 2602 (e.g., by a laser). Because the layer of material 2502 includes a photosensitive material, the layer of material 2502 will be responsive to light 2602. In this example, the portions of the layer of material 2502 exposed to light 2602 correspond to the portions of material 2502 that are retained. Figure 27 depicts the removal (e.g., by a development process) of the portions of the layer of material 2502 that were not exposed to light 2102, thereby leaving portions that correspond to the final optical filter 2702 adjacent opaque material 2002. In some examples, the end result of the manufacturing process depicted in Figure 27 is the example photomask 700 of Figures 7 and 8.

[0056] 28 through 32 illustrate an alternative exemplary stage in the manufacturing process of adding an optical filter adjacent to the distinct regions of the opaque material 2002 shown in FIG. 24. That is, FIGS. 28 through 32 are continuations of the manufacturing process depicted in FIGS. 20 through 24 that may be implemented instead of the process described in detail in connection with FIGS. 25 through 27. FIG. 28 illustrates the deposition (e.g., by vapor deposition (e.g., chemical vapor deposition (CVD), physical vapor deposition (PVD)) and / or any other suitable deposition technique) of photoresist 2802 across the transparent substrate 2004 and the distinct regions of the opaque material 2002. FIG. 29 illustrates the selective exposure of the photoresist 2802 to light 2902 (e.g., by a laser). In this example, the portions of the photoresist 2802 exposed to the light 2902 correspond to the portions of the photoresist 2802 that are retained. FIG. 30 illustrates the removal (e.g., by a development process) of portions of the photoresist 2802 that were not exposed to the light 2902, thereby defining an opening 3002 that includes a distinct region of the opaque material 2002. As shown in the illustrated example, the opening 3002 is larger than the distinct region of the opaque material 2002 to reveal an underlying portion of the transparent substrate 2004 adjacent the opaque material 2002. FIG. 31 illustrates the deposition (e.g., by deposition (e.g., chemical vapor deposition (CVD), physical vapor deposition (PVD)), sputtering, and / or any other suitable deposition technique) of a plurality of thin film layers 3102 to generate an interference filter within the opening 3002. FIG. 32 illustrates the removal (e.g., by stripping) of the remaining portions of the photoresist 2802 to expose the transparent substrate 2004. In some examples, the remaining configuration of the thin film layers 3102 corresponds to the optical filter 706 of the exemplary photomask 700 of FIGS. 7 and 8.

[0057] 33 to 35 are flow charts illustrating an exemplary method of manufacturing the exemplary photomask 700 of FIGS. 7 and 8 and the corresponding photomasks shown in FIGS. 27 and 32. However, the method may be suitably adapted to manufacture any one of the other exemplary photomasks 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900 disclosed herein. In some examples, some or all of the operations outlined in the exemplary method are performed automatically by a manufacturing facility programmed to perform the operations. Although the exemplary method of manufacturing is described with reference to the flow charts illustrated in FIGS. 33 to 35, other methods of the invention may alternatively be used. For example, the order of execution of the blocks may be changed, and / or some of the blocks described may be combined, divided, rearranged, omitted, deleted, and / or implemented in any other manner.

[0058] The example method 3300 of FIG. 33 begins in block 3302 by depositing a layer of opaque material (e.g., opaque material 2002 of FIG. 20) on a transparent substrate (e.g., transparent substrate 2004 of FIG. 20). In block 3304, the example method includes patterning the opaque material 2002 into distinct regions of opaque material 2002. In some examples, the implementation of block 3304 includes the processes described in detail in connection with FIGS. 20-24. In block 3306, the example method includes adding optical filters adjacent the distinct regions of opaque material 2002. Different ways of implementing block 3306 are described in further detail below in connection with FIGS. 34 and 35, respectively. In particular, FIG. 34 is a flow chart generally corresponding to the processes described in detail in connection with FIGS. 25-27, and FIG. 35 is a flow chart generally corresponding to the processes described in detail in connection with FIGS. 28-32.

[0059] FIG. 34 is a flow chart depicting an example method 3400 for implementing block 3306 of FIG. 33. The example method 3400 of FIG. 34 begins by generating a mixture of optically absorbing and photosensitive materials at block 3402. At block 3404, the method includes depositing a mixture layer on a transparent substrate 2004 including an area of ​​opaque material 2002 (as depicted in FIG. 25). At block 3406, the method includes exposing the mixture layer to light at a plurality of locations aligned with and extending beyond the area of ​​opaque material 2002 (as depicted in FIG. 26). At block 3408, the method includes removing excess portions of the mixture layer (as depicted in FIG. 27).

[0060] FIG. 35 is a flow chart depicting another exemplary method 3500 for implementing block 3306 of FIG. 33. The exemplary method 3500 of FIG. 35 begins in block 3502 by depositing a photoresist (e.g., photoresist 2802 of FIG. 28) on a transparent substrate 2004 including an area of ​​opaque material 2002. In block 3504, the method includes providing a plurality of openings (e.g., openings 3002 of FIG. 30) in the photoresist 2802 to expose a plurality of areas of the opaque material 2002 (as depicted in FIGS. 29 and 30) and to expose a plurality of portions of the transparent substrate 2004 adjacent to the plurality of areas of the opaque material 2002. In block 3506, the method includes depositing a material for an optical filter in the openings 3002. In some examples, the material corresponds to a plurality of thin film layers to produce an interference filter (as depicted in FIG. 31). In other examples, the openings 3002 can be filled with an absorbing material to produce an absorbing filter. At block 3508, the method includes removing remaining portions of the photoresist 2802 (as depicted in FIG. 32).

[0061] "Including" and "comprising" (and all forms and tenses thereof) are used herein as open-ended terms. Thus, whenever a claim uses any form of "include" or "comprise" (e.g., "comprises," "includes," "comprising," "including," "having," etc.) as a preamble or in any type of claim recitation, it is to be understood that additional elements, terms, etc. may be present without departing from the scope of the corresponding claim or recitation. As used herein, the phrase "at least" is open-ended in the same manner that the terms "including" and "comprising" are open-ended, for example, when used as a transition in the preamble of a claim. When the term "and / or" is used in the form, for example, A, B, and / or C, it refers to any combination or subset of A, B, C, such as (1) A alone, (2) B alone, (3) C alone, (4) A and B, (5) A and C, (6) B and C, or (7) A and B and C. When used herein in the context of describing structures, components, items, objects, and / or things, the phrase "at least one of A and B" is intended to refer to an implementation that includes either (1) at least one A, (2) at least one B, or (3) at least one A and at least one B. Similarly, when used herein in the context of describing structures, components, items, objects, and / or things, the phrase "at least one of A or B" is intended to refer to an implementation that includes either (1) at least one A, (2) at least one B, or (3) at least one A and at least one B. When used herein in the context of describing the performance or execution of a process, instruction, operation, activity, and / or step, the phrase “at least one of A and B” is intended to refer to an implementation that includes either (1) at least one A, (2) at least one B, or (3) at least one A and at least one B.Similarly, when used herein in the context of describing the performance or execution of a process, instruction, operation, activity, and / or step, the phrase “at least one of A or B” is intended to refer to an implementation that includes either (1) at least one A, (2) at least one B, or (3) at least one A and at least one B.

[0062] As used herein, a singular reference (e.g., "a", "an", "first", "second", etc.) does not exclude a plurality. The term "a" or "an" object as used herein refers to one or more of that object. The terms "a" (or "an"), "one or more", and "at least one" are used interchangeably herein. Furthermore, although individually recited, multiple means, elements or actions may be implemented by, for example, the same entity or object. Additionally, although individual features may be included in different embodiments or different claims, they may be potentially combined, and their inclusion in different embodiments or different claims does not imply that a combination of features is not feasible and / or advantageous.

[0063] As used herein, unless otherwise specified, the term "above" describes the relationship of two portions to the Earth. A first portion is above a second portion if the second portion has at least one portion between the Earth and the first portion. Similarly, as used herein, a first portion is "below" a second portion if the first portion is closer to the Earth than the second portion. As described above, a first portion can be above or below a second portion, with one or more of: with other portions therebetween, without other portions therebetween, with the first and second portions in contact, or without the first and second portions in direct contact with each other.

[0064] Notwithstanding the above, when referring to a semiconductor device (e.g., a transistor), a semiconductor die including a semiconductor device, and / or an integrated circuit (IC) package including a semiconductor die during fabrication or manufacturing, "on" does not refer to the earth, but instead to a substrate upon which the associated components are made, assembled, mounted, supported, or otherwise provided. Thus, as used herein, unless otherwise stated or implied by context, a first component (e.g., a transistor or other semiconductor device) in a semiconductor die is "on" a second component in the semiconductor die if, during fabrication / manufacturing, the first component is farther away from the substrate (e.g., a semiconductor wafer) upon which the two components are made or otherwise provided than is the second component. Similarly, unless otherwise stated or implied by context, a first component (e.g., a semiconductor die) in an IC package is "on" a second component in the IC package if, during fabrication, the first component is farther away from the printed circuit board (PCB) upon which the IC package will be mounted or attached. It is understood that a semiconductor device is often used in an orientation different from its orientation during manufacture. Thus, when referring to a semiconductor device (e.g., a transistor), a semiconductor die that includes a semiconductor device, and / or an integrated circuit (IC) package that includes the semiconductor die during use, the definition of "on" in the previous paragraph (i.e., the term "on" describes the relationship of two parts relative to the Earth) may be determined based on the context of use.

[0065] As used in this patent, a description of any part (e.g., a layer, film, area, region, or plate) being on (e.g., positioned on, located on, disposed on, or formed on) another part in any manner indicates that the referenced part is either in contact with the other part, or that the referenced part is on the other part with one or more intermediate parts disposed therebetween.

[0066] As used herein, unless otherwise specified, connection references (e.g., attached, coupled, connected, and coupled) may include intermediate members between the elements referenced by the connection reference and / or relative movement between those elements. As such, a connection reference does not necessarily imply that the two elements are directly connected and / or in fixed relationship to one another. As used herein, the phrase that any part is "in contact with" another part is defined to mean that there are no intermediate parts between the two parts.

[0067] Unless otherwise stated, descriptors such as "first," "second," "third," and the like are used herein without negatively or otherwise implying any sense of priority, physical order, placement within a list, and / or ordering in any way, but are merely used as labels and / or arbitrary names to distinguish elements to facilitate understanding of the disclosed examples. In some instances, the descriptor "first" may be used to refer to an element in the detailed description, but the same element may be referred to in the claims using a different descriptor such as "second" or "third." In such instances, it should be understood that such descriptors are merely used to separately identify those elements within the context of the description (e.g., in the claims) (wherein the elements may otherwise share the same name, for example).

[0068] As used herein, "approximately" and "about" modify their objects / values ​​to recognize the existence of potential variations that occur in real-world applications. For example, "approximately" and "about" may modify a dimension that may not be exact due to manufacturing tolerances and / or other real-world imperfections, as would be understood by one of ordinary skill in the art. For example, "approximately" and "about" may indicate that such a dimension may be within a tolerance range of ±10%, unless otherwise specified in the description below.

[0069] As used herein, the phrase "communicate" (including variations thereof) encompasses direct communication and / or indirect communication through one or more intermediate components and does not require direct physical (e.g., wired) communication and / or constant communication, and additionally includes selective communication at periodic intervals, scheduled intervals, aperiodic intervals, and / or one-time events.

[0070] As used herein, "programmable circuitry" is defined to include (i) one or more special purpose electrical circuits (e.g., application specific circuits (ASICs)) having a structure to perform a particular operation and including one or more semiconductor-based logic devices (e.g., electrical hardware implemented by one or more transistors); and / or (ii) one or more general purpose semiconductor-based electrical circuits that are programmable with instructions to perform a particular function and / or operation and include one or more semiconductor-based logic devices (e.g., electrical hardware implemented by one or more transistors). Examples of programmable circuitry include programmable microprocessors, such as a central processor unit (CPU) that can execute first instructions to perform one or more operations and / or functions; a field programmable gate array (FPGA) that can be programmed with second instructions to instantiate one or more operations and / or functions corresponding to the first instructions into the configuration and / or structure of the FPGA; a graphics processor unit (GPU) that can execute the first instructions to perform one or more operations and / or functions; a digital signal processor (DSP), XPU, network processing unit (NPU) that can execute the first instructions to perform one or more operations and / or functions; one or more microcontrollers that can execute the first instructions to perform one or more operations and / or functions; and / or integrated circuits, such as application specific integrated circuits (ASICs). For example, an XPU may be implemented by a heterogeneous computing system that includes multiple types of programmable circuitry (e.g., one or more FPGAs, one or more CPUs, one or more GPUs, one or more NPUs, one or more DSPs, etc., and / or any combination thereof) and an orchestration technique (e.g., an application programming interface (API) that can allocate a computing task to any one of multiple types of programmable circuitry that is suitable and available to perform the computing task).

[0071] As used herein, an integrated circuit / circuitry is defined as one or more semiconductor packages that include one or more circuit elements, such as transistors, capacitors, inductors, resistors, current paths, diodes, etc. For example, an integrated circuit may be implemented as one or more of an ASIC, an FPGA, a chip, a microchip, a programmable circuitry, a semiconductor substrate combining multiple circuit elements, a system on a chip (SoC), etc.

[0072] From the foregoing, it will be appreciated that exemplary systems, apparatus, products, and methods have been disclosed that incorporate optical filters into a photomask to allow selective filtering of certain wavelengths of light through certain regions of the photomask while allowing other wavelengths of light to pass through the photomask. The simultaneous use of multiple wavelengths of light allows for a photolithography process that not only takes advantage of the benefits of using relatively long wavelengths of light, but also takes advantage of the benefits of using relatively short wavelengths of light. In particular, shorter wavelengths of light have the advantage of having smaller diffraction angles, thus allowing for higher resolution patterning for smaller and / or closer features. Longer wavelengths of light can penetrate deeper into the photosensitive material (e.g., solder resist), reducing the size and associated effects of undercutting that occurs below the depth of the photosensitive material reached by the light. The disclosed systems, apparatus, products, and methods are thus related to one or more improvements in the operation of a machine, such as a computer or other electronic and / or mechanical device.

[0073] Further examples and combinations thereof include:

[0074] Example 1 includes a photolithography mask comprising a transparent substrate, an opaque material supported by the transparent substrate, the opaque material covering a first region of the transparent substrate, and an optical filter supported by the transparent substrate, the optical filter covering a second region of the transparent substrate, the second region being separate from the first region, and both the opaque material and the optical filter being spaced apart from a third region of the transparent substrate.

[0075] Example 2 includes the photolithographic mask of Example 1, where the optical filter is directly adjacent to the opaque material along the surface of the transparent substrate.

[0076] Example 3 includes the photolithography mask of Example 1, where an opaque material is between the transparent substrate and the optical filter.

[0077] Example 4 includes the photolithography mask of Example 1, where an optical filter is between the transparent substrate and the opaque material.

[0078] Example 5 includes the photolithographic mask of Example 1, where more wavelengths of light can pass through the transparent substrate than can pass through the optical filter, and more wavelengths of light can pass through the optical filter than can pass through the opaque material.

[0079] Example 6 includes the photolithographic mask of Example 5, where the transparent substrate allows the passage of both i-line and h-line light, and the optical filter allows the passage of the i-line light but filters the h-line light.

[0080] Example 7 includes the photolithography mask of Example 1, wherein the first region has a circular shape with a first diameter and the second region has a circular shape with a second diameter, the second diameter being greater than the first diameter, and the first region is centered within the second region.

[0081] Example 8 includes the photolithography mask of Example 1, wherein the opaque material has a first thickness and the optical filter has a second thickness, the second thickness being greater than the first thickness.

[0082] Example 9 includes the photolithography mask of Example 1, wherein the transparent substrate allows passage of light comprising a first wavelength and a second wavelength, and the optical filter allows passage of a first portion of the light corresponding to the first wavelength and filters a second portion of the light corresponding to the second wavelength, wherein the first wavelength is approximately 365 nanometers and the second wavelength is approximately 405 nanometers.

[0083] Example 10 includes the photolithography mask of Example 1, where the optical filter is an interference filter.

[0084] Example 11 includes the photolithographic mask of Example 1, where the optical filter is an absorptive filter.

[0085] Example 12 includes the photolithography mask of Example 1, where the opaque material is on a first surface of the transparent substrate and the optical filter is on a second surface of the transparent substrate, the first surface opposite the second surface.

[0086] Example 13 includes a photolithography mask comprising means for obstructing the passage of light, means for filtering light, and means for supporting the filtering means adjacent the obstructing means, with a portion of the supporting means spaced apart from the obstructing means and spaced apart from the filtering means.

[0087] Example 14 includes the photolithographic mask of Example 13, where the filtering means contacts an edge of the obstructing means.

[0088] Example 15 includes the photolithographic mask of Example 13, wherein the filtering means surrounds the blocking means against a surface of the supporting means.

[0089] Example 16 includes the photolithographic mask of Example 13, wherein a portion of the means for supporting permits passage of light that is filtered by the means for filtering, and the means for filtering permits passage of light that is blocked by the means for blocking.

[0090] Example 17 includes a method of manufacturing a photolithography mask, the method comprising depositing an opaque material on a glass panel, and providing an optical filter on the glass panel, the optical filter extending outwardly from an edge of the opaque material, and the glass panel extending beyond the edge of the optical filter.

[0091] Example 18 includes the method of example 17, in which providing an optical filter on the glass panel includes depositing material for the optical filter on the opaque material.

[0092] Example 19 includes the method of Example 17, further comprising: forming a mixture of an optically absorbing material and a photosensitive material; depositing the mixture on a glass panel overlying the opaque material; lithographically patterning the mixture to define a first portion of the mixture to be retained and a second portion of the mixture to be removed, the first portion being aligned with and extending beyond the opaque material, and removing the second portion of the mixture.

[0093] Example 20 includes the method of example 17, further comprising depositing a photoresist on the glass panel covering the opaque material; creating an opening in the photoresist to expose the opaque material and a portion of the glass panel adjacent the opaque material; and providing an optical filter by depositing a plurality of thin film layers in the opening, the plurality of thin film layers realizing an interference filter.

[0094] The following claims are hereby incorporated by reference into this detailed description. Although certain exemplary systems, apparatus, products, and methods have been disclosed herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all systems, apparatus, products, and methods that fall even slightly within the scope of the claims. [Other possible items] [Item 1] Transparent substrate; an opaque material supported by a transparent substrate, the opaque material covering a first region of the transparent substrate; and an optical filter supported by a transparent substrate, the optical filter covering a second region of the transparent substrate, the second region being distinct from the first region, both the opaque material and the optical filter being spaced apart from a third region of the transparent substrate; A photolithography mask comprising: [Item 2] 2. The photolithography mask of item 1, wherein the optical filter is directly adjacent to the opaque material along a surface of the transparent substrate. [Item 3] 2. The photolithography mask of item 1, wherein the opaque material is between the transparent substrate and the optical filter. [Item 4] 2. The photolithography mask of item 1, wherein the optical filter is between the transparent substrate and the opaque material. [Item 5] Item 2. The photolithography mask of item 1, wherein more wavelengths of light can pass through the transparent substrate than can pass through the optical filter, and more wavelengths of light can pass through the optical filter than can pass through the opaque material. [Item 6] Item 6. The photolithographic mask of item 5, wherein the transparent substrate allows the passage of both i-line and h-line light, and the optical filter allows the passage of the i-line light but filters the h-line light. [Item 7] 2. The photolithography mask of item 1, wherein the first region has a circular shape of a first diameter and the second region has a circular shape of a second diameter, the second diameter being larger than the first diameter, and the first region is centered within the second region. [Item 8] 2. The photolithography mask of item 1, wherein the opaque material has a first thickness and the optical filter has a second thickness, the second thickness being greater than the first thickness. [Item 9] 2. The photolithography mask of item 1, wherein the transparent substrate allows the passage of light including a first wavelength and a second wavelength, and the optical filter allows the passage of a first portion of the light corresponding to the first wavelength and filters a second portion of the light corresponding to the second wavelength, the first wavelength being approximately 365 nanometers and the second wavelength being approximately 405 nanometers. [Item 10] Item 2. The photolithography mask of item 1, wherein the optical filter is an interference filter. [Item 11] Item 2. The photolithographic mask of item 1, wherein the optical filter is an absorptive filter. [Item 12] 2. The photolithography mask of item 1, wherein the opaque material is on a first surface of a transparent substrate and the optical filter is on a second surface of the transparent substrate, the first surface being opposite the second surface. [Item 13] a means of obstructing the passage of light; means for filtering light; and Means for supporting the filtering means adjacent the blocking means Equipped with a portion of the supporting means spaced apart from the obstructing means and spaced apart from the filtering means; Photolithography mask. [Item 14] Item 14. The photolithographic mask of item 13, wherein the filtering means contacts an edge of the obstructing means. [Item 15] Item 14. The photolithography mask of item 13, wherein the filtering means surrounds the obstructing means against a surface of the supporting means. [Item 16] Item 14. The photolithographic mask of item 13, wherein a portion of the supporting means allows passage of light that is filtered by the filtering means, and the filtering means allows passage of light that is blocked by the blocking means. [Item 17] 1. A method of manufacturing a photolithography mask comprising: depositing an opaque material on the glass panel; and Providing an optical filter on the glass panel Equipped with the optical filter extends outwardly from an edge of the opaque material, and the glass panel extends beyond the edge of the optical filter; method. [Item 18] Item 18. The method of item 17, wherein providing an optical filter on the glass panel comprises depositing material for the optical filter on an opaque material. [Item 19] forming a mixture of an optically absorbing material and a photosensitive material; depositing the mixture onto a glass panel covering an opaque material; lithographically patterning the mixture to define a first portion of the mixture to be retained and a second portion of the mixture to be removed, the first portion aligned with and extending beyond the opaque material; and Removing a second portion of the mixture. 18. The method of claim 17, further comprising: [Item 20] depositing a photoresist on the glass panel covering the opaque material; providing an opening in the photoresist to expose the opaque material and to expose a portion of the glass panel adjacent the opaque material; and providing an optical filter by depositing a plurality of thin film layers in the aperture; Further comprising: The multiple thin film layers realize an interference filter. Item 18. The method according to item 17.

Claims

1. A transparent substrate; an opaque material supported by the transparent substrate, the opaque material covering a first region of the transparent substrate; and an optical filter supported by the transparent substrate, the optical filter covering a second region of the transparent substrate, the second region being distinct from the first region, and both the opaque material and the optical filter being spaced apart from a third region of the transparent substrate; A photolithography mask comprising:

2. The photolithography mask of claim 1 , wherein the optical filter is directly adjacent to the opaque material along a surface of the transparent substrate.

3. The photolithography mask of claim 1 or 2, wherein the opaque material is between the transparent substrate and the optical filter.

4. The photolithography mask of claim 1 or 2, wherein the optical filter is between the transparent substrate and the opaque material.

5. 3. The photolithography mask of claim 1 or 2, wherein more wavelengths of light can pass through the transparent substrate than can pass through the optical filter, and more wavelengths of light can pass through the optical filter than can pass through the opaque material.

6. 6. The photolithography mask of claim 5, wherein the transparent substrate allows the passage of both i-line and h-line light, and the optical filter allows the passage of i-line light but filters h-line light.

7. 3. The photolithography mask of claim 1, wherein the first region has a circular shape of a first diameter and the second region has a circular shape of a second diameter, the second diameter being greater than the first diameter, and the first region is centrally disposed within the second region.

8. 3. The photolithography mask of claim 1, wherein the opaque material has a first thickness and the optical filter has a second thickness, the second thickness being greater than the first thickness.

9. 3. The photolithography mask of claim 1, wherein the transparent substrate allows the passage of light having a first wavelength and a second wavelength, and the optical filter allows the passage of a first portion of the light corresponding to the first wavelength and filters a second portion of the light corresponding to the second wavelength, the first wavelength being approximately 365 nanometers and the second wavelength being approximately 405 nanometers.

10. The photolithography mask of claim 1 or 2, wherein the optical filter is an interference filter.

11. The photolithography mask of claim 1 or 2, wherein the optical filter is an absorptive filter.

12. 3. The photolithography mask of claim 1, wherein the opaque material is on a first surface of the transparent substrate and the optical filter is on a second surface of the transparent substrate, the first surface being opposite the second surface.

13. Means for obstructing the passage of light; means for filtering light; and Means for supporting said filtering means adjacent said blocking means. Equipped with a portion of the supporting means spaced apart from the obstructing means and spaced apart from the filtering means; Photolithography mask.

14. 14. The photolithographic mask of claim 13, wherein the means for filtering contacts an edge of the means for obstructing.

15. 15. The photolithographic mask of claim 13 or 14, wherein the filtering means surrounds the obstructing means against a surface of the supporting means.

16. 15. The photolithography mask of claim 13 or 14, wherein a portion of the means for supporting allows passage of light that is filtered by the means for filtering, and the means for filtering allows passage of light that is blocked by the means for blocking.

17. 1. A method of manufacturing a photolithography mask, comprising: depositing an opaque material on a glass panel; and providing an optical filter on said glass panel. Equipped with the optical filter extends outwardly from an edge of the opaque material, and the glass panel extends beyond the edge of the optical filter. method.

18. 20. The method of claim 17, wherein providing the optical filter on the glass panel comprises depositing material for the optical filter over the opaque material.

19. forming a mixture of an optically absorbing material and a photosensitive material; depositing the mixture on the glass panel overlying the opaque material; lithographically patterning the mixture to define a first portion of the mixture to be retained and a second portion of the mixture to be removed, the first portion aligned with and extending beyond the opaque material; and Removing the second portion of the mixture.

19. The method of claim 17 or 18, further comprising:

20. depositing a photoresist on the glass panel covering the opaque material; providing an opening in the photoresist to expose the opaque material and to expose a portion of the glass panel adjacent the opaque material; and providing said optical filter by depositing a plurality of thin film layers in said aperture. Further comprising: The plurality of thin film layers realizes an interference filter.

19. The method of claim 17 or 18.

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