SEMICONDUCTOR WAFER AND METHOD FOR MANUFACTURING SEMICONDUCTOR WAFER
20230163015 · 2023-05-25
Assignee
Inventors
Cpc classification
H01L22/34
ELECTRICITY
H01L21/78
ELECTRICITY
H01L23/544
ELECTRICITY
International classification
H01L21/67
ELECTRICITY
Abstract
A semiconductor wafer is diced along a plurality of dicing lines in a first direction and a second direction different from the first direction so that a chip is cut out from an effective area. The semiconductor water includes a film formation pattern. At least one dicing line included in the plurality of dicing lines is an on-pattern dicing line which overlaps the film formation pattern in its entire or partial length.
Claims
1. A semiconductor wafer being diced along a plurality of dicing lines in a first direction and a second direction different from the first direction so that a chip is cut out from an effective area, the semiconductor wafer comprising a film formation pattern, and at least one dicing line included in the plurality of dicing lines being an on-pattern dicing line which overlaps the film formation pattern in an entire or a partial length of the on-pattern dicing line.
2. The semiconductor wafer according to claim 1, wherein the on-pattern dicing line is first five or less dicing lines in order of cutting in a dicing process among the plurality of dicing lines in the first direction.
3. The semiconductor wafer according to claim 1, wherein the on-pattern dicing line is first three or more and five or less dicing lines in order of cutting in a dicing process among the plurality of dicing lines in the first direction, and first three or more and five or less dicing lines in order of cutting in the dicing process among the plurality of dicing lines in the second direction.
4. The semiconductor wafer according to claim 1, wherein an on-pattern dicing line portion that is a portion of the on-pattern dicing line overlapping the film formation pattern is a portion having a length of ½ of an entire length of the on-pattern dicing line.
5. The semiconductor wafer according to claim 1, wherein an on-pattern dicing line portion that is the portion of the on-pattern dicing line overlapping the film formation pattern exists only in an ineffective area which is an area other than the effective area of the semiconductor wafer.
6. The semiconductor wafer according to claim 1, wherein the chip includes a semiconductor substrate, and an interlayer film, an electrode, and a surface protective film formed on the semiconductor substrate, and the film formation pattern is made of a material same as a material of at least one of the interlayer film, the electrode, and the surface protective film.
7. The semiconductor wafer according to claim 1, wherein a width of the film formation pattern is smaller than a width of the on-pattern dicing line, and the film formation pattern is riot in contact with the chip adjacent to the on-pattern dicing line.
8. The semiconductor wafer according to claim 1, wherein a width of the film formation pattern is equal to a width of the on-pattern dicing line, and the film formation pattern is in contact with a side surface of the chip adjacent to the on-pattern dicing line.
9. The semiconductor wafer according to claim 1, wherein a width of the film formation pattern is greater than a width of the on-pattern dicing line, and the film formation pattern covers a terminal portion of the chip adjacent to the on-pattern dicing line.
10. The semiconductor wafer according to claim 6, wherein a width of the film formation pattern is greater than a width of the on-pattern dicing line, and the film formation pattern covers an upper surface of the chip except for an opening provided in the chip for electrically connecting the electrode to an outside of the chip.
11. The semiconductor wafer according to claim 1, wherein the width of the film formation pattern is greater than a width of a dicing blade that dices the semiconductor wafer.
12. The semiconductor wafer according to claim 1, wherein the film formation pattern covers entirety of the on-pattern dicing line in a longitudinal direction.
13. The semiconductor wafer according to claim 1, wherein a plurality of the film formation patterns is intermittently arranged in a longitudinal direction of the on-pattern dicing line.
14. The semiconductor wafer according to claim 1, wherein a longitudinal direction or an arrangement direction of the film formation pattern has an angle with respect to the longitudinal direction of the on-pattern dicing line within a range in which the film formation pattern does not deviate from the on-pattern dicing line.
15. The semiconductor wafer according to claim 1, wherein the film formation pattern has a function as an alignment mark, a target, or a reference marking.
16. The semiconductor wafer according to claim 1, wherein the film formation pattern has a function as a monitor pattern.
17. The semiconductor wafer according to claim 1, wherein the film formation pattern is a pattern in which a name, a logo, or a management number is drawn.
18. The semiconductor wafer according to claim 1, wherein a semiconductor material of the semiconductor wafer is Si, SiC, or GaN.
19. A method for manufacturing the semiconductor wafer according to claim 1, the method comprising: (a) a step of drawing a first photomask in a central portion of a semiconductor substrate; and (b) a step of drawing a second photomask or a third photomask on an outer peripheral portion surrounding the central portion of the semiconductor substrate, the first, second and third photomasks including a chip pattern area in which a pattern of the chip is formed, and a dicing line pattern area in which a pattern of the plurality of dicing lines is formed, the dicing line pattern area surrounding the chip pattern area and having a first portion that extends in the first direction and a second portion that extends in the second direction, a pattern for a film formation pattern for drawing the film formation pattern in the first portion and the second portion being formed in the dicing line pattern area of the second photomask, the pattern for the film formation pattern being formed in one of the first portion and the second portion in the dicing line pattern area of the third photomask, and the greater warpage of the semiconductor substrate, the greater a width of the outer peripheral portion.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DESCRIPTION OF THE PREFERRED EMBODIMENTS
A. First Preferred Embodiment
[0049]
[0050] The semiconductor wafer 101 is cut in the x direction and the y direction along a plurality of dicing lines (hereinafter also referred to as DLs). In
[0051] The semiconductor wafer 101 includes an effective area 10 in which a chip 12 cut out by dicing exists and an ineffective area 11 other than the effective area 10.
[0052] A film formation pattern is formed in the semiconductor wafer 101 of the first preferred embodiment. At least one of the plurality of DLs for cutting the semiconductor wafer 101 is an on-pattern DL 43 overlapping the film formation pattern in its entire or partial length. A portion of the on-pattern DL 43 overlapping the film formation pattern is referred to as an on-pattern DL portion 44.
[0053] In the example of
[0054] Hereinafter, layouts of the on-pattern DLs 43 and the inn-pattern DL portions 44 in the semiconductor wafer 101 will be described.
[0055] <A-1-1. Arrangement of On-Pattern DL Portion 44>
[0056] The arrangement of the on-pattern DL portions 44 is assumed as follows.
[0057] (1) As illustrated in
[0058] (2) As illustrated in
[0059] <A-1-2. Number of On-Pattern DLs 43>
[0060] The number of on-pattern DLs 43 is assumed to be as follows.
[0061] (1) The on-pattern DL 43 may be the first DL or the first and second DLs in the x direction. Here, the first DL refers to a DL cut first into the semiconductor wafer 101 in a dicing process, and the second DL refers to a DL cut second into the semiconductor wafer 101 in the dicing process. Hereinafter, the number of DLs is counted in order of cutting into the semiconductor wafer 101 in the dicing process.
[0062]
[0063] (2) The on-pattern DLs 43 may be the first to third DLs, the first to fourth DLs, or the first to fifth DLs 41 in the x direction.
[0064] (3) The on-pattern DLs 43 may be the first to third, first to fourth, or first to fifth DLs 41 in the x direction, and first to third, first to fourth, or first to fifth DLs 42 in the y direction.
[0065] <A-1-3. Length of On-Pattern DL Portion>
[0066] The length of the on-pattern DL portion 44 is assumed as follows.
[0067] The on-pattern DL portion 44 is part or entirety of the on-pattern DL 43. That is, the length of the on-pattern DL portion 44 is part or entirety of the entire length of the on-pattern DL 43.
[0068]
[0069]
[0070]
[0071] In the examples of
[0072] In the example of
[0073] In the example of
[0074] <A-2. Effect>
[0075] The semiconductor wafer 101 according to the first preferred embodiment is diced along the plurality of dicing lines 41, 42 in the x direction and the y direction so that the chip 12 is cut out from the effective area 10. The semiconductor wafer 101 includes the film formation pattern 3. At least one dicing line included in the plurality of dicing lines 41, 42 is the on-pattern dicing line 43 which overlaps the film formation pattern 3 in its entire or partial length. As a result, it is possible to reduce chipping or cracks during dicing due to inherent stress of warpage or distortion of the semiconductor wafer 101.
[0076] By forming the film formation pattern 3 on the on-pattern DL 43, the following effects are obtained.
[0077] (A) The amount of chipping or cracks spreading from the side surface to the lower surface of the semiconductor wafer 101 can be reduced.
[0078] (B) Conventionally, the size of chipping or a crack in the lower surface of the semiconductor wafer 101 is about half of the size of chipping or a crack in the side surface of the semiconductor wafer 101; however, this size can be further reduced.
[0079] (C) The chipping amount in the upper surface of the semiconductor wafer 101 can be reduced.
[0080] In addition, the warpage stress inherent in the semiconductor wafer 101 may be released only once at one of warped or distorted portions (unduly the outer periphery of the wafer) in the semiconductor wafer 101. The portion where the warpage stress inherent in the semiconductor wafer 101 is released can be designated by the number and direction of the on-pattern DL 43 and the length of the on-pattern DL portion 44.
[0081] That is, in the ineffective area 11 or the effective area 10 on the outer periphery of the semiconductor wafer 101, by providing a film formation pattern in the vicinity of a defective product in electrical characteristics or appearance inspection even for several DLs 41, 42 cut into the semiconductor wafer 101 first, the amount of chipping or cracks can be reduced without affecting the chips 12 as products.
[0082] When the semiconductor wafer 101 is diced using two dicing blades, the amount of chipping (cracks) can be reduced by providing a film formation pattern on either one of the DLs 41, 42 in the semiconductor wafer 101.
[0083] In the DL first cut into the semiconductor wafer 101, if ½ or more of the DL length is cut, the size of chipping (crack) greatly decreases thereafter. Therefore, in the outermost DLs 41, 42 of the semiconductor wafer 101, if about ½ to ⅔ of the entire length of the DL is set as the on-pattern DL portion 44, chipping (cracks) can be halved.
[0084] The length of chipping (crack) corresponding to the amount of warpage of the semiconductor wafer 101 is roughly known. If the maximum of five DLs are set as the on-pattern DL portions 44, the chipping crack) amount can be reduced.
[0085] According to the semiconductor wafer 101 of the first preferred embodiment, a high yield after dicing can be obtained by arranging the on-pattern DL portion 44 in the ineffective area 11 or an area where a defective product is located in the effective area 10.
B. Second Preferred Embodiment
[0086] <B-1. Photomask>
[0087] In a second preferred embodiment, a manufacturing process of the semiconductor wafer 101 according to the first preferred embodiment will be described. In a front-end process of semiconductor manufacturing, a film formation pattern is formed on the on-pattern DL 43 of the semiconductor wafer 101. Hereinafter, a state of the semiconductor wafer 101 before the pattern of the chips 12 or the film formation pattern is formed is referred to as a base wafer BW. Hereinafter, a photomask used in a photolithography process for forming a film formation pattern on the base wafer BW will be described.
[0088]
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[0090]
[0091] <B-2. Photolithography Process>
[0092] In the photolithography process, the first to third photomasks FM1 to FM3 are used in combination according to the magnitude of warpage or distortion of the base wafer BW.
[0093] In a case where warpage or distortion of the base wafer BW is small, the second photomask FM2 or the third photomask FM3 is drawn in one column from the outer periphery of the base wafer BW as illustrated in
[0094] In a case where warpage or distortion of the base wafer BW is large, the range in which the second photomask FM2 or the third photomask FM3 is drawn is increased according to the degree of warpage or distortion. In the example of
[0095] <B-3. Effect>
[0096] The method for manufacturing the semiconductor wafer according to the second preferred embodiment includes: (a) a step of drawing the first photomask FM1 on the central portion of a semiconductor substrate 17; and (b) a step of drawing the second photomask FM2 or the third photomask FM3 on the outer peripheral portion surrounding the central portion of the semiconductor substrate 17. Each of the first, second, and third photomasks FM2, and FM3 includes the chip pattern area 51 in which a chip pattern is formed, and the DL pattern area 52 in which a pattern of the plurality of dicing lines 41, 42 is formed. The DL pattern area 52 surrounds the chip pattern area 51 and has the first portion extending in the first direction and the second portion extending in the second direction. In the DL pattern area 52 of the second photomask FM2, the pattern 53 for a film formation pattern for drawing a film formation pattern in the first portion and the second portion is formed. In the DL pattern area 52 of the third photomask FM3, the pattern 53 for a film formation pattern is formed in one of the first portion and the second portion. The greater the warpage of the semiconductor substrate 17, the greater the width of the outer peripheral portion.
[0097] Therefore, according to the method for manufacturing a semiconductor wafer of the second preferred embodiment, by selectively using the first to third photomasks FM1 to FM3 according to the location in the semiconductor wafer 101, it is possible to designate the portion where the film formation pattern 3 is formed in the semiconductor wafer 101. Therefore, it is possible to freely form a film formation pattern in a warped or distorted portion on the semiconductor wafer 101. In addition, by minimizing the number of film formation patterns, clogging of the dicing blade due to the film formation patterns can be minimized.
C. Third Preferred Embodiment
[0098] In a third preferred embodiment, a detailed configuration of the film formation pattern in the semiconductor wafer 101 according to the first preferred embodiment will be described.
[0099] <C-1. Configuration>
[0100]
[0101] A width W1 of the film formation pattern 3 is smaller than a width W2 of the on-pattern DL 43 and greater than a width W3 of the dicing blade.
[0102] The film property of the film formation pattern 3 is a type that can be manufactured in a wafer front-end process, and constitutes the chip 12, which is a product. The film formation pattern 3 includes a single layer or a plurality of layers.
[0103] When the semiconductor wafer 101 is diced, the semiconductor wafer 101 is fixed on a UV tape 14 as illustrated in
[0104] Another film 166, a field film 165, an interlayer film 164, an electrode 163, a glass coating 162, and a polyimide film 161 are formed on the semiconductor substrate 17 in the wafer front-end process. The glass coating 162 is made of an oxide film, a nitride film, or the like. The electrode 163 is made of Al, AlSi, Poly-Si, or the like. The field film 165 and the other film 166 are oxide films.
[0105] Therefore, the film formation pattern 3 can have any one of the following configurations (1) to (9).
[0106] (1) Lamination of a polyimide film, a glass coating, an electrode, and an interlayer film
[0107] (2) Lamination of a polyimide film, a glass coating, and an electrode
[0108] (3) Lamination of a polyimide film and a glass coating
[0109] (4) Lamination of a glass coating and an electrode
[0110] (5) Lamination of an electrode and an interlayer film
[0111] (6) Only an electrode
[0112] (7) Only an interlayer film
[0113] (8) Lamination of a polyimide film, a glass coating, and an interlayer film
[0114] (9) Only a polyimide film
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[0120] (1) As illustrated in
[0121] (2) As illustrated in
[0122] (3) As illustrated in
[0123] (4) As illustrated in
[0124] In any of the above patterns, in order to reduce chipping or cracks in the semiconductor wafer 101 in dicing, the width W1 of the film formation pattern 3 is desirably greater than the width W3 of the dicing blade 8.
[0125] Specifically, the ratio W1/W3 of the width W1 of the film formation pattern 3 to the width W3 of the dicing blade 8 is preferably greater than 1.0 and less than 2.4 in the patterns (1) and (2), and is preferably 2.4 or more in the patterns (3) and (4).
[0126] By defining the relationship between the width W1 of the film formation pattern 3 and the width W3 of the dicing blade 8 as described above the remains of the film formation pattern 3 continues to exist in part of the DL on the chip after dicing. Therefore, it is easier to find out that the present configuration is adopted from the appearance or the like at the initial stage of product analysis.
[0127] In the pattern (1) in which the film formation pattern 3 is arranged in the island shape in the on-pattern DL 43, since the film formation pattern 3 is not in contact with the chip terminal portion 121, the film formation pattern 3 may be a conductive film. In the other patterns (2), (3), and (4), since the film formation pattern 3 is in contact with the chip terminal portion 121, the film formation pattern 3 needs to be a non-conductive film.
[0128] In the patterns (3) and (4), the film formation pattern 3 may be formed using an existing protective film instead of additionally forming a film on the on-pattern DL 43 in the wafer front-end process. That is, the film formation pattern 3 may be formed by extending an existing protective film such as the polyimide film 161 or the glass coating 162 which conventionally only extends to the chip terminal portion 121, into the on-pattern DL 43.
[0129] The following patterns are assumed as planar forms of the film formation pattern 3.
[0130] (1) As illustrated in
[0131] (2) As illustrated in
[0132] (3) As illustrated in
[0133]
[0134] As illustrated in
[0135]
[0136] <C-2. Effect>
[0137] In the semiconductor wafer 101 according to the third preferred embodiment, the chip 12 includes the semiconductor substrate 17, and the interlayer film 164, the electrode 163, and a surface protective film that are formed on the semiconductor substrate 17, and the film formation pattern 3 is made of the same material as that of at least one of the interlayer film 164, the electrode 163, and the surface protective film. As described above, according to the semiconductor wafer 101, the film formation pattern 3 can be made of a film constituting the chip 12. Therefore, it is not necessary to add a special photolithography process for forming the film formation pattern 3 in the on-pattern DL 43, and an increase in man-hours can be avoided. In addition, by selecting one film from the plurality of films constituting the chip 12 or combining a plurality of films constituting the chip 12 and adopting the combined films as the film formation pattern 3, an appropriate chipping reduction effect can be obtained according to the degree of warpage or distortion of the semiconductor wafer 101.
D. Fourth Preferred Embodiment
[0138] In a fourth preferred embodiment, functions of the film formation pattern 3 of the semiconductor wafer 101 will be described.
[0139] <D-1. TEG>
[0140]
[0141] The plurality of pads 22 is arranged on the semiconductor substrate 17 at regular intervals on the on-pattern DL 43. The measurement target element 20 is disposed between the adjacent pads 22. The wiring 21 connects the pad 22 and the measurement target element 20. Although not illustrated. In
[0142] As illustrated in
[0143] The size of the pad 22 is arbitrary.
[0144] As illustrated in
[0145] <D-2. Mark or the Like>
[0146] Hereinafter, film formation patterns each having a function as a mark or the like will be described.
[0147]
[0148]
[0149]
[0150] The film formation pattern 3 illustrated in each of
[0151] <D-3. Monitor Pattern>
[0152] Hereinafter, film formation patterns each having a function as a monitor pattern will be described.
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[0160] The film formation patterns 3 as the monitor patterns described above are film formation patterns for the purpose of various measurements, inspections, and finish observation when a product chip is formed by repeating film formation, impurity diffusion, the photolithography process, and the like mainly in the wafer front-end process.
[0161] <D-4. Name or the Like>
[0162] Hereinafter, film formation patterns in which a name or the like is drawn will be described.
[0163]
[0164]
[0165]
[0166] In addition, the film formation pattern 3 may be one on which a registered trademark is drawn.
[0167] In the present preferred embodiment, the film formation patterns 3 which have various functions or in which names and the like are drawn have been described. However, the film formation pattern 3 may not have these functions, and a name may not be drawn in the film formation pattern 3.
[0168] In addition, in the third preferred embodiment, it has been described that a film of a type that can be manufactured by processing of the wafer frontend process and constitutes the chip 12 is adopted as the film formation pattern 3. However, the film formation pattern 3 is not indispensable for the configuration of the chip 12, and may be newly added.
[0169] <D-5. Effect>
[0170] According to the semiconductor wafer 101 of the fourth preferred embodiment, the film formation pattern 3 can be used not only for the purpose of reducing chipping but also for other functions such as TEG.
[0171] Note that the preferred embodiments can be freely combined, and the preferred embodiments can be appropriately modified or omitted.
[0172] While the disclosure has been shown and described in detail, the foregoing description is in all aspects illustrative and not restrictive. It is therefore understood that numerous modifications and variations can be devised.