Photomask construction and phototreatment method

Abstract

This application relates to photomask constructions and photo processing methods. Some embodiments include a photomask including first pattern features and second pattern features. A first optimal dose of actinic radiation is associated with the first pattern features, and a second optimal dose of the actinic radiation is associated with the second pattern features. The second pattern features are larger than the first pattern features. Each of the second pattern features has a configuration including a center region laterally surrounded by an outer region, where the center region has a different opacity than the outer region. The configuration of the second pattern features balances the second optimal dose of the actinic radiation within about 5% of the first optimal dose of the actinic radiation. Some embodiments include photo processing methods.

Description

Technical Field

[0001] Photomask construction, optical processing methods, and integrated circuit manufacturing (e.g., NAND memory manufacturing). Background Technology

[0002] Photolithography is commonly used during the fabrication of integrated circuits on semiconductor wafers. More precisely, a form of radiative energy passes through a radiation patterning tool and is transferred to a radiation-sensitive material associated with the semiconductor wafer. This radiative energy can be referred to as photochemical energy and can be light in the ultraviolet (UV) range, deep UV range, etc. The radiation-sensitive material is a photoimageable material, such as a photoresist.

[0003] Radiation patterning tools may be referred to as photomasks or photomasks. The term "photomask" is conventionally understood to refer to a mask that defines a pattern of the entire wafer, and the term "photomask" is conventionally understood to refer to a patterning tool that defines a pattern of only a portion of the wafer. However, the terms "photomask" (or more generally, "mask") and "photomask" are often used interchangeably in modern terminology, such that either term can refer to a radiation patterning tool covering a portion or the entire wafer. For the purposes of interpreting this disclosure and the appended claims, unless expressly stated otherwise, the term "photomask" is understood to be used interchangeably with conventional photomasks and photomasks.

[0004] Some of the applications discussed in the following embodiments involve memory manufacturing (e.g., NAND memory manufacturing). Figure 1 shows a block diagram of a prior art device 1000 including: a memory array 1002 having a plurality of memory cells 1003 arranged in rows and columns; access lines 1004 (e.g., word lines for conducting signals WL0 to WLm); and first data lines 1006 (e.g., bit lines for conducting signals BL0 to BLn). Access lines 1004 and first data lines 1006 are used to transfer information to and from memory cells 1003. Row decoder 1007 and column decoder 1008 decode address signals A0 to AX on address lines 1009 to determine which memory cells in memory cells 1003 are to be accessed. Sensing amplifier circuit 1015 operates to determine the value of information read from memory cells 1003. I / O circuit 1017 transmits information values ​​between memory array 1002 and input / output (I / O) lines 1005. Signals DQ0 to DQN on I / O lines 1005 can represent the values ​​of information read from or to be written to memory cells 1003. Other devices can communicate with device 1000 via I / O lines 1005, address lines 1009, or control lines 1020. Memory control unit 1018 controls memory operations to be performed on memory cells 1003 and utilizes signals on control line 1020. Device 1000 can receive supply voltage signals Vcc and Vss on first supply line 1030 and second supply line 1032, respectively. Device 1000 includes selection circuit 1040 and input / output (I / O) circuit 1017. Selection circuit 1040 can respond to signals CSEL1 to CSELn via I / O circuit 1017 to select signals on first data line 1006 and second data line 1013, the signals representing values ​​of information to be read from or programmed into memory cell 1003. Column decoder 1008 can selectively activate CSEL1 to CSELn signals based on address signals A0 to AX on address line 1009. Selection circuit 1040 can select signals on first data line 1006 and second data line 1013 to enable communication between memory array 1002 and I / O circuit 1017 during read and program operations.

[0005] The memory array 1002 of Figure 1 may be a NAND memory array, and Figure 2 shows a block diagram of a three-dimensional NAND memory device 200 that can be used with the memory array 1002 of Figure 1. Device 200 includes multiple strings of charge storage devices. In a first direction (Z-Z'), each string of charge storage devices may include, for example, thirty-two charge storage devices stacked one on top of the other, where each charge storage device corresponds to, for example, one of thirty-two rows (e.g., row 0 to row 31). The charge storage devices of the respective strings may share a common channel region, for example, a common channel region formed in a pillar of a respective semiconductor material (e.g., polysilicon), around which the charge storage device strings are formed. In a second direction (X-X'), for example, each of sixteen first groups of multiple strings may include, for example, eight strings sharing multiple (e.g., thirty-two) access lines (i.e., "global control gate (CG) lines", also known as word lines WL). Each of the access lines may couple to charge storage devices within a row. When each charge storage device includes a cell capable of storing two bits of information, charge storage devices coupled by the same access line (and therefore corresponding to the same row) can logically be grouped into, for example, two pages, such as P0 / P32, P1 / P33, P2 / P34, etc. In a third direction (Y-Y'), each of eight second groups of multiple strings may include sixteen strings coupled by corresponding data lines of eight data lines. The size of a memory block may include 1,024 pages and approximately 16 MB (e.g., 16WL × 32 rows × 2 bits = 1,024 pages / block, block size = 1,024 pages × 16KB / page = 16 MB). The number of strings, rows, access lines, data lines, first groups, second groups, and / or pages may be larger or smaller than those shown in Figure 2.

[0006] Figure 3 shows a cross-sectional view of a memory block 300 of the 3D NAND memory device 200 of Figure 2 in the X-X' direction. The memory block 300 contains fifteen strings of charge storage devices from one of sixteen first groups of strings described in Figure 2. The multiple strings of the memory block 300 can be grouped into multiple subsets 310, 320, 330 (e.g., tile columns), such as tile columns. I Puzzle Series j and puzzle series KEach subset (e.g., a tile array) comprises a “partial block” of memory block 300. A global drain-side select-gate (SGD) line 340 may be coupled to the SGDs of the plurality of strings. For example, the global SGD line 340 may be coupled to a plurality of (e.g., three) sub-SGD drivers 332, 334, 336 via a corresponding one of them, where each sub-SGD line corresponds to a corresponding subset (e.g., a tile array). Each of the sub-SGD drivers 332, 334, 336 may simultaneously couple or disconnect the SGD of the corresponding partial block (e.g., a tile array) of strings, independently of the SGDs of the strings of other partial blocks. A global source-side select-gate (SGS) line 360 ​​may be coupled to the SGS of the plurality of strings. For example, a global SGS line 360 ​​may be coupled to a plurality of sub-SGS lines 362, 364, 366 via a corresponding one of a plurality of sub-SGS drivers 322, 324, 326, wherein each sub-SGS line corresponds to a corresponding subset (e.g., a tile column). Each of the sub-SGS drivers 322, 324, 326 may couple or disconnect the SGS of the corresponding partial block (e.g., a tile column) string independently of the SGS of the strings of other partial blocks. A global access line (e.g., a global CG line) 350 may be coupled to a charge storage device corresponding to a corresponding row of each of the plurality of strings. Each global CG line (e.g., global CG line 350) may be coupled to a plurality of sub-access lines (e.g., sub-CG lines) 352, 354, 356 via a corresponding one of a plurality of sub-string drivers 312, 314, 316. Each of the substring drivers can simultaneously couple or disconnect the charge storage device corresponding to the corresponding sub-block and / or row, independently of the charge storage devices of other sub-blocks and / or other rows. The charge storage devices corresponding to the corresponding subset (e.g., sub-block) and the corresponding row may include a “partial row” (e.g., a single “patch”) of charge storage devices. The string corresponding to the corresponding subset (e.g., sub-block) may be coupled to a corresponding one of sub-sources 372, 374, and 376 (e.g., “patch source”), wherein each sub-source is coupled to a corresponding power source.

[0007] Alternatively, the NAND memory device 200 is described with reference to the schematic illustration of FIG4.

[0008] Memory array 200 includes word lines 2021 to 202 N And bit lines 2281 to 228 M .

[0009] Memory array 200 also includes NAND strings 2061 to 206 M Each NAND string contains 2081 to 208 charge storage transistors. NCharge storage transistors can store charge using floating gate materials (e.g., polysilicon) or charge trapping materials (e.g., silicon nitride, metal nanodots, etc.).

[0010] Charge storage transistor 208 is located at the intersection of word line 202 and string 206. Charge storage transistor 208 represents a non-volatile memory cell for storing data. The charge storage transistor 208 of each NAND string 206 is connected in series from source to drain between a source select device (e.g., source-side select gate SGS) 210 and a drain select device (e.g., drain-side select gate SGD) 212. Each source select device 210 is located at the intersection of string 206 and source select line 214, and each drain select device 212 is located at the intersection of string 206 and drain select line 215. Select devices 210 and 212 can be any suitable access device and are generally illustrated by the boxes in FIG. 4.

[0011] The source of each source select device 210 is connected to a common source line 216. The drain of each source select device 210 is connected to the source of the first charge storage transistor 208 corresponding to the NAND string 206. For example, the drain of source select device 2101 is connected to the source of the charge storage transistor 2081 corresponding to the NAND string 2061. The source select device 210 is connected to the source select line 214.

[0012] The drain of each drain selector 212 is connected to the bit line (i.e., digital line) 228 at its drain contact. For example, the drain of drain selector 2121 is connected to bit line 2281. The source of each drain selector 212 is connected to the drain of the last charge storage transistor 208 of the corresponding NAND string 206. For example, the source of drain selector 2121 is connected to the charge storage transistor 208 of the corresponding NAND string 2061. N The drain electrode.

[0013] The charge storage transistor 208 includes a source 230, a drain 232, a charge storage region 234, and a control gate 236. The control gate 236 of the charge storage transistor 208 is coupled to a word line 202. Columns of the charge storage transistor 208 are those transistors coupled to a given positioning line 228 within a NAND string 206. Rows of the charge storage transistor 208 are those transistors typically coupled to a given word line 202.

[0014] It is often necessary to simultaneously pattern features of different sizes during the fabrication of integrated circuits (e.g., integrated memory). However, such patterning is difficult to perform, at least in part, due to the difficulty in forming photomasks suitable for efficiently utilizing a single dose of photochemical radiation to pattern features of different sizes. There is a need to develop new photomask configurations and new methods for optical processing using such photomask configurations during the fabrication of integrated circuits. Summary of the Invention

[0015] In one aspect, this application provides a light processing method comprising: forming a photoimageable material over a substrate having a first region to be formed with a first target feature and a second region to be formed with a second target feature, the first target feature being smaller than the second target feature; forming a photomask configured to pattern the first and second target features within the photoimageable material, the photomask having a first pattern feature patterned with the first target feature and a second pattern feature patterned with the second target feature, each of the second pattern features having a configuration including a central region and an outer region, wherein the central region has an opacity different from the outer region, the first and second pattern features having a first and second optimal dose of photochemical radiation associated therewith, the configuration of the second pattern features such that the second optimal dose of photochemical radiation is balanced within about 5% of the first optimal dose of photochemical radiation; and allowing photochemical radiation to pass through the photomask and onto the photoimageable material to pattern the first and second target features within the photoimageable material.

[0016] In another aspect, this application provides a light processing method comprising: forming a photoimageable material over a substrate; forming a photomask configured to pattern a first target feature and a second target feature within the photoimageable material, the photomask having a first pattern feature patterning the first target feature and a second pattern feature patterning the second target feature, the second pattern feature being larger than the first pattern feature, each of the second pattern features comprising a central region and an outer region laterally surrounding the central region, wherein the central region has an opacity different from the outer region, the central region being suitably configured such that an optimal dose of photochemical radiation passing through the second pattern feature is within about 5% of the optimal dose of photochemical radiation passing through the first pattern feature, the suitable configuration of the central region of the second pattern feature being determined by: 1) determining an optimal dose of photochemical radiation for the first pattern feature; 2) determining a relationship between the configuration of the central region of the second pattern feature and the optimal dose of photochemical radiation for the second pattern feature; and 3) using the relationship to confirm the suitable configuration of the central region of the second pattern feature; and allowing photochemical radiation to pass through the photomask and onto the photoimageable material to pattern the first target feature and the second target feature within the photoimageable material.

[0017] In another aspect, this application provides a photomask comprising: a first pattern feature having a first optimal dose of photochemical radiation associated therewith; a second pattern feature having a second optimal dose of photochemical radiation associated therewith, the second pattern feature being larger than the first pattern feature, each of the second pattern features having a configuration comprising a central region laterally surrounded by an outer region, wherein the central region has an opacity different from the outer region; and a configuration of the second pattern feature such that the second optimal dose of photochemical radiation is balanced within approximately 5% of the first optimal dose of photochemical radiation. Attached Figure Description

[0018] Figure 1 shows a block diagram of a prior art memory device having a memory array with memory cells.

[0019] Figure 2 shows a schematic diagram of a prior art memory array in the form of a 3D NAND memory device.

[0020] Figure 3 shows a cross-sectional view of the prior art 3D NAND memory device of Figure 2 in the X-X' direction.

[0021] Figure 4 is a schematic diagram of a conventional NAND memory array.

[0022] Figure 5 An illustrated top view showing a photoimageable material (left side of the figure) and a pattern formed within the photoimageable material (right side of the figure).

[0023] Figure 6 A schematic side view of an instance device configured for optical processing.

[0024] Figure 7 This is a top view of the instance area of ​​the instance photomask.

[0025] Figure 8 and 9 For crossing Figure 7 A graph showing the relationship between the intensity of photochemical radiation in the instance region of the instance mask and distance.

[0026] Figure 10 exhibit Figure 7 One of the regions is modified to change the relationship between the intensity of radiation passing through the region and distance, and a graphical relationship between the intensity of photochemical radiation passing through the region and distance is shown before and after the modification.

[0027] Figure 11 This is a flowchart description of an example process for an example embodiment.

[0028] Figure 12This diagram shows a top view of a photoimageable material (left side of the image) and a photomask (right side of the image). The photomask is used to form the illustrated pattern within the photoimageable material.

[0029] Figure 13 and 13A These are, respectively, a top view and a cross-sectional side view of the instance pattern feature (patterned feature) of the instance photomask. Figure 13A The view along Figure 13 Line AA.

[0030] Figure 14 and 14A These are, respectively, a top view and a cross-sectional side view of the instance pattern feature (patterned feature) of the instance photomask. Figure 14A The view along Figure 14 Line AA.

[0031] Figures 15A to 15D This is a top view of the instance pattern features (patterned features) of the instance photomask. Detailed Implementation

[0032] Some embodiments include a photomask having first and second patterned features, wherein the second patterned feature is larger than the first patterned feature. The second patterned feature can be configured to balance the optimal dose of its associated photochemical radiation such that the optimal dose of photochemical radiation associated with the second feature is approximately the same as the optimal dose associated with the first feature, even if the first patterned feature is smaller than the second patterned feature. Some embodiments include an optical processing (optical patterning) method. Reference Figure 5 Example implementations are described up to 15.

[0033] refer to Figure 5 Component 10 is shown on the left side of the diagram at the initial processing level "A" and on the right side of the diagram at the subsequent processing level "B".

[0034] Component 10 at processing stage “A” includes an imagerable material 12 formed over an underlying substrate 14 (wherein a region of substrate 14 is visible at processing stage “B”). Component 10 includes a pair of memory array regions 16a and 16b, and another region 18 between memory array regions 16a and 16b. Regions 16a and 16b ultimately contain memory cells. The memory cells may be NAND memory cells formed along vertically extending channel regions of the type described above with reference to FIG. 2, wherein the memory cells are along a common channel corresponding to a string of memory cells (e.g., a NAND string). Each of the memory cells in an individual string may be located within one of rows 0 to 31 of FIG. 2. The global control gate (CG) lines (word lines) of FIG. 2 extend laterally along the rows and between the memory cells, wherein the word lines also extend to the row decoder circuitry as described above with reference to FIG. 1.

[0035] In some embodiments, the positions of vertically extending channel material pillars within the memory arrays 16a and 16b are patterned using the opening 20 of the processing stage "B".

[0036] In some embodiments, region 18 may correspond to an interconnect region (e.g., may include a stepped region) and may be used to form connections to word lines. Such electrical connections may extend to line decoder circuitry and to associated word line driver circuitry. Alternatively and / or additionally, interconnects formed within region 18 may extend to other components associated with the NAND memory, such as source structures, SGS devices, etc. Alternatively and / or additionally, structures resembling functional interconnects may be formed within region 18 and may be used solely for structural support rather than for electrical connections (i.e., at least some of the structures formed within region 18 may correspond to so-called "dummy" structures).

[0037] exist Figure 5 In the illustrated embodiment, interconnect region 18 can be considered to be close to memory array regions 16a and 16b, and located between the illustrated memory array regions.

[0038] Photoimageable material 12 is exposed to patterned photochemical radiation to form a first opening 20 within memory array regions 16a and 16b, and a second opening 22 within an intermediate region 18. In some embodiments, the first opening 20 may be considered to correspond to a first target feature formed within the photoimageable material 12, and the second opening 22 may be considered to correspond to a second target feature formed within the photoimageable material. Notably, the second target feature 22 is much smaller than the first target feature 20. In some embodiments, each of the first target features 20 may occupy an area at least about 50% larger than the area occupied by each of the target features 22, and at least about twice the area occupied by each of the target features 22.

[0039] In the illustrated embodiment, the first target feature 20 and the second target feature 22 are substantially circular features (i.e., circular within reasonable manufacturing and measurement tolerances). In other embodiments, the first target feature 20 and the second target feature 22 may have other suitable shapes, including, for example, elliptical, polygonal, etc.; and may or may not have the same shape as each other.

[0040] exist Figure 5 Arrow 24 illustrates the light processing used to pattern the optically imageable material 12. This light processing can be achieved using, as shown in the reference... Figure 6 The appropriate light mask as described.

[0041] To be precise, Figure 6A substrate 14 is shown, on which an imageable material 12 is disposed. The substrate is oriented relative to an optical processing device 26. The device 26 includes a photomask 28, a pair of lenses 30 and 32 (i.e., a projection lens and a condenser lens), an aperture 34, and a source 36 for generating electromagnetic radiation (wherein the electromagnetic radiation is illustrated by dashed lines 38).

[0042] Figure 6 The electromagnetic radiation can be called photochemical radiation because it has a suitable wavelength that causes chemical changes within the photoimageable material 12. These chemical changes cause the exposed areas of the photoimageable material to be more soluble in the developer than the unexposed areas (in applications where the photoimageable material 12 is a positive resist), or less soluble in the developer than the unexposed areas (in applications where the photoimageable material 12 is a negative resist).

[0043] The photomask 28 includes a bulk material 29 and includes features for patterning. Figure 5 Pattern features of openings 20 and 22 (not shown). Pattern features may be, for example, openings extending into bulk material 29, opaque areas above bulk material 29, and / or other configurations. Bulk material 29 may comprise any suitable composition, and in some embodiments may comprise silicon (e.g., monocrystalline silicon) having suitable transmittance.

[0044] In an attempt to manufacture a suitable structure for forming large opening 20 and small opening 22 ( Figure 5 Difficulties are encountered when patterning the features of both, because the optimal dose of photochemical radiation used for the photomask features associated with the large opening 22 is usually different from the optimal dose used for the photomask features associated with the small opening 20.

[0045] Figure 7 Regions 40 and 42 of the light mask 28 are shown. Region 40 includes features configured to pattern large target features (e.g., Figure 5 The large pattern feature 44 of the opening 20), and the region 42 includes small target features configured to be patterned (e.g., Figure 5 Small patterned feature 46 (opening 22). Feature 44 is shown as a rectangle and feature 46 is shown as a square. In other embodiments, features 44 and 46 may have the same shape as each other (e.g., both may be squares, both may be rectangles, etc.). If features 44 and 46 are both used to pattern circular target features in a photoimageable material (e.g., ... Figure 5 (As shown in the image), then features 44 and 46 can both be squares.

[0046] Figure 8 and 9 Illustrate major feature 44 and minor feature 46 graphically. Figure 7The optical proximity correction (OPC) threshold levels of the pattern features are shown. The OPC threshold level of small feature 46 is illustrated as OPC threshold-1 and is shown as size X1; while the OPC threshold level of large feature 44 is illustrated as OPC threshold-2 and is shown as size X2. Notably, X2 is much smaller than X1. The OPC threshold level of the pattern feature is negatively correlated with the optimal dose suitable for that pattern feature. Therefore, the significant difference between X1 and X2 makes it difficult to properly optimize the single dose of pattern features 44 and 46. In practice, a compromise dose is used in conventional applications, where the compromise dose is suboptimal for both pattern features 44 and 46.

[0047] One aspect of some of the embodiments presented herein is the recognition that the optimal dose for a larger pattern feature 44 can be modified by changing the configuration of this feature to include an embedded portion (i.e., a central region with an opacity different from the rest of the feature), while still maintaining the ability of the modified pattern feature to produce the desired target feature as photochemical radiation passes through it. The embedded portion can be considered as an instance of a sub-resolution auxiliary feature (SRAF).

[0048] Figure 10 The formation of the built-in portion 48 within pattern feature 44 is illustrated graphically. Specifically, Figure 10 The left side shows the initial (unmodified) pattern feature 44, and a graph showing the OPC threshold level (size x2) associated with this feature. Figure 10 The right side shows a modified feature 44 containing a built-in portion 48, and the modified pattern feature 44 shows an OPC threshold level of size X3 (OPC threshold - 3), where size X3 is very similar to size X1 of the OPC threshold level of the small pattern feature 46. Figure 8 ).

[0049] In some embodiments, the optimal dose of photochemical radiation for the modified large pattern feature 44 may be within about 5% of the optimal dose of photochemical radiation for the small pattern feature 46. In other words, if the small pattern feature has an optimal dose D1, then the modified large pattern feature 44 may have an optimal dose in the range of about (D1 - 0.5D1) to about (D1 + 0.5D1). The optimal dose may be measured in any suitable unit, such as millijoules per centimeter. 2 (mJ / cm 2 In some embodiments, the modified large pattern feature 44 may have an optimal dose of photochemical radiation that is within about 1% of the optimal dose for the small pattern feature 46, within about 0.3% of the optimal dose for the small pattern feature, or substantially the same as the optimal dose for the small pattern feature (wherein the term “substantially the same” means the same within reasonable tolerances of manufacture and measurement).

[0050] The built-in portion 48 can be considered to correspond to the central region 50 of the modified pattern feature 44. The outer region 52 of the pattern feature 44 laterally surrounds the central region 50. The central region 50 has a different opacity than the outer region 52. The central region may have a lower opacity (higher transmittance, higher transparency) or a higher opacity (lower transmittance, lower transparency) than the outer region, depending on whether the photomask is used to pattern a positive or negative resist.

[0051] The modified pattern feature 44 can be considered to include the first area A1. Figure 10 In the illustrated embodiment where the modified pattern feature 44 is rectangular, this area can be calculated as length (L1) multiplied by width (W1); that is, A1 = L1 × W1. The central region 50 of the modified pattern feature 44 can be considered to include a second area A2, which in the illustrated embodiment can be calculated as L2 × W2. In some embodiments, the second area A2 may include approximately 5% to approximately 95% of the first area A1, or approximately 20% to approximately 60% of the first area A1, etc.

[0052] The configuration (e.g., size, shape, composition, etc.) of the built-in portion 48 (central area 50) of the modified pattern feature 44 can be determined using any suitable method. (See reference) Figure 11 Describe the instance method.

[0053] At the initial step I, at least one simulation of the smaller target sub-component (i.e., the small feature pattern 46, which may be referred to as the first feature pattern in some embodiments) is run to obtain an appropriate size for the smaller pattern for image quality.

[0054] In subsequent step II, the dose level for the smaller target (i.e., the first feature pattern 46) of the optimal size for the component is determined. This dose level may be referred to as the optimal dose for the photochemical radiation of the first feature pattern 46.

[0055] In subsequent step III, a hole (sub-resolution auxiliary feature, SRAF) is modeled in the polygon of the larger target sub-component (i.e., the large feature pattern 44, which may be referred to as the second feature pattern in some embodiments).

[0056] In subsequent step IV, the size of the pore (SRAF) changes with the simulation, and the optimal dose for the larger target sub-component (second feature 44) is determined based on the simulation features.

[0057] In subsequent step V, the SRAF configuration is analyzed against the optimal dose confirmed in step IV (i.e., data points are compared with each other) to determine the central region of the second pattern feature 44. Figure 10 The relationship between the simulated configuration of 50) and the optimal dose of photochemical radiation suitable for this type of second characteristic.

[0058] In the final step VI, a SRAF configuration is determined such that the optimal dose in step V is approximately the same as the optimal dose in step II. In other words, the relationship from step V is used to confirm a suitable configuration for the central region 50 of the second pattern feature 44, such that the optimal dose of photochemical radiation passing through the second pattern feature 44 is comparable to the optimal dose of photochemical radiation passing through the first pattern feature 46. The comparable optimal dose passing through the modified second pattern feature 44 may be within approximately 5% of the optimal dose of photochemical radiation passing through the first pattern feature 46, within approximately 1% of the optimal dose of photochemical radiation passing through the first pattern feature, within approximately 0.5% of the optimal dose of photochemical radiation passing through the first pattern feature, etc. In some embodiments, the optimal dose of photochemical radiation passing through the modified second pattern feature 44 may be substantially consistent with the optimal dose of photochemical radiation passing through the first pattern feature 46.

[0059] Figure 12 This demonstrates the relationship between the example photomask 28 and the patterned photoimageable material 12 of component 10. Figure 12 Component 10 and Figure 5 The components shown at level "B" are consistent. Photomask 28 includes regions 56a and 56b, which are used to pattern target features 20 of memory array regions 16a and 16b, respectively. Photomask 28 also includes region 58, which is located between regions 56a and 56b and is used to pattern target features 22 within interconnect region 18.

[0060] Regions 56a and 56b of photomask 28 include a larger pattern feature (second pattern feature) 44, and a central region 58 includes a smaller pattern feature (first pattern feature) 46. The second pattern feature 44 of photomask 28 is modified to include an embedded portion (central region) 50, wherein such a central region is laterally surrounded by an outer region 52. The modified feature pattern 44 may have the same (or at least equivalent) optimal dose of photochemical radiation as feature pattern 46, such that a common optimal dose of photochemical radiation can pass through all features 44 and 46 to pattern target features 20 and 22 within the photoimageable material 12 of component 10. This can advantageously improve the patterning of the array of target features 20 and 22 relative to a method of attempting to form target features similar to features 20 and 22 of component 10 by allowing a suboptimal dose of photochemical radiation to pass through the pattern features of the photomask. The patterning described herein can facilitate increased integration levels because patterning enables the formation of target openings 20 and 22 with high precision and accuracy.

[0061] It is noteworthy that the second pattern feature 44 is in Figure 12 It is displayed as a square instead of a square. Figure 7 and 10 A rectangle. This type of change in the shape of a pattern feature emphasizes that the pattern feature can have any suitable shape, and the shape of the pattern feature can be adapted for a specific application.

[0062] The second pattern feature 44 is larger than the first pattern feature 46, and may be larger by any suitable amount. In some embodiments, the second pattern feature 44 is at least about 50% larger than the first pattern feature (i.e., the area of ​​the second pattern feature is at least about 50% larger than the area of ​​the first pattern feature). In some embodiments, the second pattern feature 44 is at least about twice the size of the first pattern feature, at least about 2.5 times the size of the first pattern feature, at least about three times the size of the first pattern feature, etc.

[0063] Similar to the reference above can be used. Figure 5 and 6 The described process is used to form Figure 12 The components 10 have openings 20 and 22. Specifically, photochemical radiation can pass through photomask 28 to pattern the photochemical radiation, and the patterned photochemical radiation may affect the photoimageable material 12 to change the solubility of the photoimageable material in the developer solution. Depending on whether the photoimageable material is a positive or negative material (e.g., a positive or negative resist), areas of the photoimageable material 12 exposed to photochemical radiation will become more soluble in the developer solution or less soluble. In any case, the photochemical radiation passing through photomask 28 and onto the photoimageable material 12 patterns the first target feature 20 and the second target feature 22 within the photoimageable material (specifically, creating a pattern of exposed and unexposed areas within the photoimageable material). Depending on whether the photoimageable material is a positive or negative material, the first target feature 20 and the second target feature 22 are developed by using the developer solution to remove the exposed or unexposed areas of the photoimageable material.

[0064] As discussed above, the central region 50 of the modified pattern feature 44 may be less opaque than the outer region 52 of such modified pattern features, or it may be more transparent than the outer region 52. Figure 13 and 14 This indicates that the central area 50 is less transparent than the outer area 52. Figure 13 ) and the central area is more transparent than the outer area 52 ( Figure 14 ) instance configuration.

[0065] refer to Figure 13 and 13A The photomask 28 is shown as an opening (window) extending therein corresponding to the outer region 52. Therefore, the outer region 52 is more transparent (more transparent) than the central region 50.

[0066] refer to Figure 14 and 14A The photomask 28 is shown to include an opaque blocking material 60 corresponding to the outer region 52. Therefore, the outer region 52 is less opaque (less transmissive) than the central region 50.

[0067] Figure 13 and 14 The embodiment described is an example of forming a central region 50 with a different opacity than the outer region 52. Other configurations of the central region 50 and / or the outer region 52 may be utilized in other applications.

[0068] The example embodiment of the modified pattern feature 44 described above shows that the modified pattern feature is quadrilateral (square or rectangle) and has an outer region 52 having a substantially uniform lateral thickness surrounding the central region 50. Figures 15A to 15D This describes the additional instance configuration of the modified pattern feature 44. Figure 15A and 15B This illustrates an embodiment where the outer region 52 does not have a substantially uniform lateral thickness surrounding the central region 50. Instead, Figure 15C and 15D An embodiment is shown in which the outer region 52 has a substantially uniform lateral thickness surrounding the central region 50. Figure 15D This demonstrates an example where the modified pattern feature 44 is not a quadrilateral.

[0069] The components and structures discussed above can be utilized within integrated circuits (where the term "integrated circuit" refers to electronic circuits supported by a semiconductor substrate); and can be incorporated into electronic systems. Such electronic systems can be used in, for example, memory modules, device drivers, power modules, communication modems, processor modules, and special-purpose modules, and can comprise multi-layered, multi-chip modules. Electronic systems can be any of the following wide range of systems: for example, cameras, wireless devices, displays, chipsets, set-top boxes, games, lighting systems, vehicles, clocks, televisions, cellular phones, personal computers, automobiles, industrial control systems, aircraft, etc.

[0070] Unless otherwise specified, the various materials, substances, compositions, etc. described herein can be formed by any suitable method now known or to be developed, including, for example, atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etc.

[0071] The terms “dielectric” and “insulating” are used to describe materials having insulating electrical properties. These terms are considered synonymous in this disclosure. The term “dielectric” in some cases and the term “insulating” (or “electrically insulating”) in others may be used within this disclosure to provide linguistic variation to simplify the premises in the appended claims, rather than to indicate any significant chemical or electrical differences.

[0072] The terms "electrical connection" and "electrical coupling" are both used in this disclosure. The terms are considered synonymous. One term may be used in some cases and another in others to provide linguistic variation within this disclosure to simplify the premises of the appended claims.

[0073] The specific orientations of the various embodiments in the figures are for illustrative purposes only, and in some applications, embodiments may be rotated relative to the shown orientation. The descriptions provided herein and the appended claims relate to any structure having the described relationships between various features, regardless of whether the structure is in the specific orientation of the figures or rotated relative to such orientation.

[0074] Unless otherwise specified, the cross-sectional views in the accompanying drawings show only the features within the plane of the cross-section and do not show the material behind the plane of the cross-section in order to simplify the drawings.

[0075] When a structure is referred to as "on another structure," "adjacent to another structure," or "against another structure," the structure may be directly on the other structure or there may be an intervening structure. Conversely, when a structure is referred to as "directly on another structure," "directly adjacent to another structure," or "directly against another structure," there is no intervening structure. The terms "directly below," "directly above," etc., do not indicate direct physical contact (unless explicitly stated otherwise), but instead indicate upright alignment.

[0076] A structure (such as a layer, material, etc.) may be described as “vertically extending” to indicate that the structure typically extends upward from the underlying substrate (e.g., a base plate). A vertically extending structure may or may not extend substantially orthogonally relative to the upper surface of the substrate.

[0077] Some embodiments include an optical processing method. An optically imageable material is formed over a substrate. The substrate has a first region where a first target feature is to be formed and a second region where a second target feature is to be formed. The first target feature is smaller than the second target feature. A photomask is configured to pattern the first and second target features within the optically imageable material. The photomask has a first patterned feature patterned with the first target feature and a second patterned feature patterned with the second target feature. Each of the second patterned features has a configuration including a central region and an outer region, wherein the central region has a different opacity than the outer region. The first and second patterned features have first and second optimal doses of photochemical radiation associated with them. The configuration of the second patterned features balances the second optimal dose of photochemical radiation within approximately 5% of the first optimal dose of photochemical radiation. Photochemical radiation passes through the photomask and onto the optically imageable material to pattern the first and second target features within the optically imageable material.

[0078] Some embodiments include an optical processing method. An optically imageable material is formed over a substrate. A photomask is formed, wherein the photomask is configured to pattern first and second target features within the optically imageable material. The photomask has a first patterned feature patterned with the first target feature and a second patterned feature patterned with the second target feature. The second patterned feature is larger than the first patterned feature. Each of the second patterned features includes a central region and an outer region laterally surrounding the central region, wherein the central region has a different opacity than the outer region. The central region is suitably configured such that the optimal dose of photochemical radiation passing through the second patterned feature is within approximately 5% of the optimal dose of photochemical radiation passing through the first patterned feature. The suitable configuration of the central region of the second patterned feature is determined by: 1) determining the optimal dose of photochemical radiation for the first patterned feature;

[0079] 2) Determine the relationship between the configuration of the central region of the second patterned feature and the optimal dose of photochemical radiation used for the second patterned feature; and 3) Use the relationship to confirm the appropriate configuration of the central region of the second patterned feature. Photochemical radiation passes through a photomask and onto a photoimageable material to pattern the first and second target features within the photoimageable material.

[0080] Some embodiments include a photomask comprising a first pattern feature and a second pattern feature. A first optimal dose of photochemical radiation is associated with the first pattern feature, and a second optimal dose of photochemical radiation is associated with the second pattern feature. The second pattern feature is larger than the first pattern feature. Each of the second pattern features has a configuration comprising a central region laterally surrounded by an outer region, wherein the central region has a different opacity than the outer region. The configuration of the second pattern features balances the second optimal dose of photochemical radiation within approximately 5% of the first optimal dose of photochemical radiation.

[0081] As per the regulations, the subject matter disclosed herein has been described in more or less specific language regarding structural and methodological features. However, it should be understood that the claims are not limited to the specific features shown and described, as the apparatus disclosed herein includes exemplary embodiments. Therefore, the claims have the full scope as stated in the writings and should be properly interpreted in accordance with the principle of equivalence.

Claims

1. A light processing method, comprising: An imageable material is formed on a substrate, the substrate having a first region to be formed with a first target feature and a second region to be formed with a second target feature, wherein the first target feature is smaller than the second target feature; A photomask is formed to pattern the first target feature and the second target feature within the optically imageable material; The photomask has a first pattern feature patterning the first target feature and a second pattern feature patterning the second target feature; the first pattern feature has a single opacity; each of the second pattern features has a configuration including a central region and an outer region, wherein the central region has a different opacity than the outer region, and the central region is more opaque than the outer region; the first pattern feature and the second pattern feature have a first optimal dose and a second optimal dose of photochemical radiation associated therewith; the configuration of the second pattern feature balances the second optimal dose of the photochemical radiation within approximately 5% of the first optimal dose of the photochemical radiation; as well as The photochemical radiation is passed through the photomask and onto the photoimageable material to pattern the first target feature and the second target feature within the photoimageable material.

2. The method of claim 1, wherein the second optimal dose of the photochemical radiation is within about 1% of the first optimal dose of the photochemical radiation.

3. The method of claim 1, wherein the second optimal dose of the photochemical radiation is substantially equal to the first optimal dose of the photochemical radiation.

4. The method of claim 1, wherein the central region of the second pattern feature comprises 5% to 95% of the total area of ​​the second pattern feature.

5. The method of claim 1, wherein the central region of the second pattern feature comprises 20% to 60% of the total area of ​​the second pattern feature.

6. The method of claim 1, wherein the substrate is used for a NAND memory assembly; wherein the second target feature is located within a memory array region of the NAND memory assembly, and wherein the first target feature is located within a second region adjacent to the memory array region.

7. The method of claim 6, wherein the memory array region is one of two memory array regions of the NAND memory component, and wherein the second region is located between the two memory array regions.

8. The method according to claim 1, wherein the photoimageable material is a positive resist.

9. The method according to claim 1, wherein the photoimageable material is a negative resist.

10. The method of claim 1, wherein the central region of the second pattern feature is a sub-resolution auxiliary feature.

11. A light processing method, comprising: A light-imageable material is formed on top of a substrate; A photomask is formed, configured to pattern first and second target features within the optically imageable material; The photomask has a first pattern feature patterned to the first target feature and a second pattern feature patterned to the second target feature; the second pattern feature is larger than the first pattern feature; the first pattern feature has a single opacity; each of the second pattern features includes a central region and an outer region laterally surrounding the central region, wherein the central region has a different opacity than the outer region, and the central region is more opaque than the outer region; the central region is suitably configured such that the optimal dose of photochemical radiation passing through the second pattern feature is within approximately 5% of the optimal dose of photochemical radiation passing through the first pattern feature; The appropriate configuration of the central region of the second pattern feature is determined by: 1) determining the optimal dose of photochemical radiation for the first pattern feature; 2) determining the relationship between the configuration of the central region of the second pattern feature and the optimal dose of photochemical radiation for the second pattern feature; And 3) using the relationship to confirm the appropriate configuration of the central region of the second pattern feature; as well as The photochemical radiation is passed through the photomask and onto the photoimageable material to pattern the first target feature and the second target feature within the photoimageable material.

12. The method of claim 11, wherein the optimal dose of the photochemical radiation passing through the second pattern feature is within about 1% of the optimal dose of the photochemical radiation passing through the first pattern feature.

13. The method of claim 11, wherein the optimal dose of photochemical radiation passing through the second pattern feature is within about 0.5% of the optimal dose of photochemical radiation passing through the first pattern feature.

14. The method of claim 11, wherein the optimal dose of the photochemical radiation passing through the second pattern feature is substantially the same as the optimal dose of the photochemical radiation passing through the first pattern feature.

15. The method of claim 11, wherein the central region of the second pattern feature comprises 5% to 95% of the total area of ​​the second pattern feature.

16. The method of claim 11, wherein the central region of the second pattern feature comprises 20% to 60% of the total area of ​​the second pattern feature.

17. The method of claim 11, wherein the first pattern feature and the second pattern feature are quadrilateral features.

18. The method of claim 17, wherein the first target feature and the second target feature are substantially circular features.

19. The method of claim 11, wherein the central region of the second pattern feature is a sub-resolution auxiliary feature.

20. A photomask, comprising: A first pattern feature having a first optimal dose of photochemical radiation associated therewith, the first pattern feature having a single opacity; A second pattern feature having a second optimal dose of the photochemical radiation associated therewith; the second pattern feature is larger than the first pattern feature; each of the second pattern features has a configuration comprising a central region laterally surrounded by an outer region, wherein the central region has a different opacity than the outer region, and the central region is more opaque than the outer region; and The configuration of the second pattern feature balances the second optimal dose of the photochemical radiation within approximately 5% of the first optimal dose of the photochemical radiation.

21. The photomask of claim 20, wherein the second optimal dose of the photochemical radiation is within about 1% of the first optimal dose of the photochemical radiation.

22. The photomask of claim 20, wherein the second optimal dose of the photochemical radiation is substantially equal to the first optimal dose of the photochemical radiation.

23. The photomask of claim 20, wherein the outer region has a substantially uniform lateral thickness surrounding the central region.

24. The photomask of claim 20, wherein the outer region does not have a substantially uniform lateral thickness surrounding the central region.

25. The photomask of claim 20, wherein the second pattern feature is at least 50% larger than the first pattern feature.

26. The photomask of claim 20, wherein the second pattern feature is at least twice the size of the first pattern feature.

27. The photomask of claim 20, comprising a bulk material, said bulk material comprising silicon.

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