CN100405548C - bump manufacturing process and structure - Google Patents

Abstract

A bump manufacturing process and structure includes forming a passivation layer with a planarized surface covering a bonding pad of a substrate, forming an opening through the passivation layer to expose a contact surface of the bonding pad, and forming a bump on the contact surface and the planarized surface. The protective layer has the flattened surface, so that the bonding pad can be reduced, the mechanical strength of the protective layer in the edge area of the bonding pad is increased, the bump has a larger effective area during pressing, the selection space of the anisotropic conductive film is larger, the short circuit and electric leakage probability in the bump gap are reduced, and the pressing yield and the conductive quality of the bump are improved.

Description

Bump manufacturing process and structure

technical field

The present invention relates to a manufacturing process and structure of a bump, in particular to a manufacturing process and structure of a planarized bump.

Background technique

Wire bonding (wire bonding), tape automatic bonding (Tap Automatic Bonding; TAB) and flip chip (flip chip) bonding are typical technologies for integrated circuit (IC) packaging. Generally speaking, wire bonding is used in low-density wiring packages with less than about 300 contacts, high-connection-density packages for TAB applications reach about 600 contacts, and flip-chip bonding provides higher connection density packages with more than 600 contacts. . Packages that use flip-chip bonding must first grow bumps on the bonding pad of the IC so that they can be bonded to the chip on glass (Chip On Glass; COG), chip on board (Chip On Board; COB), chip Lamination in Chip On Film (COF) or other packaging procedures. In order to reduce telecommunication interference, increase adhesion and conductivity, gold is generally used for bumps, which makes the production of bumps expensive and difficult. Therefore, the process and structure of bump manufacturing has become an important issue for packaging technology improvement. On the other hand, the density and performance of the package also limit the size and performance of the chip. As ICs continue to shrink, if the packaging density and performance cannot be improved, for example, the size and pitch of the bumps are limited, or the conductivity of the bumps is not good enough, then the packaging will become a bottleneck for the further reduction of the chip size.

1 shows a known gold bump structure 10, the bonding pad 14 on the substrate 12 is partially covered by the protective layer 16, and the under-bump metallization (Under-Bump Metallization; UBM) 18 is exposed on the contact surface of the bonding pad 14 and the protective layer. On layer 16, gold film 20 and gold bumps 22 are on UBM 18. Typically, the bonding pad 14 is made of aluminum, the protective layer 16 includes a layer of silicon dioxide 24 and a layer of silicon nitride 26 , and the UBM 18 is a stack of titanium and tungsten. The gold film 20 is made by sputtering, and its crystal particles are finer, which can increase the adhesion between the gold bump 22 and the UBM 18 . The gold bump 22 is made by electroplating, and its crystal particles are larger and its hardness is higher. Due to the step 28 formed by the covering 16 at the edge of the bond pad 14 , the edge of the upper surface of the bump 22 also forms a step 30 . Therefore, only the central recessed region 32 becomes an effective region during pressing, and the roughness h of this upper surface is approximately 2 μm. If a sufficiently large effective area 32 is to be obtained, the bonding pad 14 must be larger. If only the width of the bump 22 is increased, as shown in FIG. 2 , since the upper surface of the bump 22 is uneven, the increased area 34 is still an inactive area , the size of the active area 32 does not change. FIG. 3 shows the situation that there are a plurality of bumps 22 on the substrate 12, the width of the bonding pad 14 is w1, the bump gap is g, the bump pitch is p, and the width w2 of the bump 22 is not greater than the width of the bonding pad 14. w1 , therefore, active area 32 is very small compared to bond pad 14 . In order to increase the effective area 32 , the bonding pads 14 are required to be larger, so the chip's contact density is low, and the size of the chip cannot be reduced. Large bonding pads 14 also lead to large bump pitch p. If the bump gap g remains unchanged, the only way to increase the joint density is to shrink the bonding pads 14. However, shrinking the bonding pads 14 will cause the effective area 32 to shrink. Therefore, the known technology There are insurmountable difficulties.

A known bumping process is shown in FIGS. 4A to 4E . In FIG. 4A , a covering layer 16 with a thickness of about 1.2 μm is deposited over the bonding pads 14 of the substrate 12 . In FIG. 4B, the etching protective layer 16 forms an opening 36 to expose the bonding pad 14, and then a step 38 is also formed on the edge of the bonding pad 14. When the thickness of the protective layer 16 is thicker, the height of the step 38 is higher, and the opening 36 deeper. In FIG. 4C, titanium/tungsten with a thickness of about 800 angstroms is deposited as UBM18, and a gold film 20 with a thickness of about 800 angstroms is deposited. Because of the steps 38, the resulting steps 40 are wider. When the thickness of UBM18 is thicker, The width of the depression 42 is narrower. After patterning the UBM 18 and the gold film 20 is shown in FIG. 4D . In FIG. 4E , a gold bump 22 is grown from the gold film 20 to a thickness of about 17 μm. It has been shown from the foregoing process that the step 38 cannot be avoided. Therefore, a smaller effective area 32 must be obtained in the end, and the thicker the sheath 16 is, the greater the roughness h is, and the thicker the UBM 18 is, the smaller the effective area 32 is. Although the IC process can reduce the size of the components, the packaging technology in the back stage cannot keep up with the speed of the shrinking of the size of the components, thus limiting the minimum size of the chip.

The known bump structures also have disadvantages during pressing. Referring to the COG structure 44 in FIG. 5 , when the bump 22 is bonded to the wire 48 on the glass substrate 46 , an anisotropic conductive film (Anisotropic Conductive Film; ACF) 50 is used as an interface between the two. ACF is a colloidal polyethylene containing conductive particles, and its conductive particles are compressed during pressing to form a conductive path in the pressing direction. Since the surface roughness of the bump 22 is about 2 μm, the size of the conductive particles 52 in the ACF 50 must be greater than 3 μm to obtain good conduction between the bump 22 and the wire 48 . However, the conductive particles 52 with a larger particle size lead to a smaller number trapped in the effective region 32 during lamination, so the contact resistance is larger, and the conductive quality after lamination is poor. on the other hand. During lamination, the conductive particles 56 in the gaps 54 of the bumps are easily squeezed and deformed due to their large particle size, causing short circuit and electric leakage between adjacent bumps 22 , resulting in a low lamination yield. If the conductive particles 52 with a smaller particle size are used, a good connection between the bump 22 and the wire 48 cannot be provided, so the known technology has insurmountable difficulties. With the reduction of IC size and the demand for high I/O count, the bonding pad 14 of the IC is also reduced, and the effective area 32 is thus reduced, resulting in a reduction in the bonding yield and the conductive quality after bonding. Furthermore, a natural disadvantage of the flip-chip package is that the mechanical strength of the edge region 58 of the bump 22 is weak, and it is easy to be broken due to lateral pulling. However, to obtain a smaller roughness h on the surface of the bump 22, the height of the step 28 must be reduced, so the thickness of the sheath 16 is thinner, and the disadvantage of weaker mechanical strength cannot be overcome.

Therefore, an improved bump manufacturing process and structure is expected.

Contents of the invention

The main purpose of the present invention is to provide a planarized bump manufacturing process and structure to improve various shortcomings of the known technology.

According to the present invention, a bumping process includes forming a cover layer having a planarized surface to cover a bonding pad on a substrate, forming an opening through the cover layer to expose a contact surface of the bonding pad, and A bump is formed on the contact surface of the bonding pad and the planarized surface of the protective layer.

According to the present invention, a bump structure includes a protective layer having a planarized surface covering a portion of a bonding pad on a substrate, and a bump contacts the contact surface of the bonding pad not covered by the protective layer and the protective layer. The planarized surface of the layer.

Preferably, the covering comprises a stack of layers of different hardness.

It is also preferred that the contact surface has an elongated shape.

Due to the flattened surface of the sheath, the bonding pad can be reduced, the mechanical strength of the sheath is increased in the edge region of the bonding pad, the bump has a larger effective area during lamination, anisotropy The selection space of the conductive film is large, the short circuit and electric leakage rate in the gap between the bumps are reduced, and the pressing yield and the conductive quality of the bump are improved.

Description of drawings

1 is a cross-sectional view of a known gold bump structure;

Fig. 2 is a schematic diagram after enlarging the bump 22 in Fig. 1;

3 is a schematic diagram of a plurality of bumps 22 on the substrate 12;

4A to 4E are known bump manufacturing processes;

Figure 5 is a known COG structure;

6A and 6B are cross-sectional views of the gold bump structure of the present invention;

7A and 7B are top views of the gold bump structure of the present invention;

8A to 8G are the first embodiment of the gold bump manufacturing process of the present invention;

9A to 9D are the second embodiment of the gold bump manufacturing process of the present invention;

Figure 10 is the COG structure of the present invention; and

Fig. 11 is a gold bump structure with increased thickness of the protective layer.

Description of main component symbols:

10: Gold bump structure

12: Substrate

14: Bonding Pad

16: Sheath

18: Bump Underlying Metal

20: gold film

22: Gold bump

24: Silica

26: Silicon nitride

28: Ladder

30: Ladder

32: Effective area

34: invalid area

36: opening

38: Ladder

40: Ladder

42: sunken

44: COG structure

46: Glass substrate

48: Wire

50: Anisotropic conductive film

52: Conductive particles

54: Bump clearance

56: Conductive particles

58: Edge area

60: Gold bump structure

62: Bonding Pad

64: Sheath

66: Gold bump

68: invalid area

70: effective area

72: contact surface

74: contact surface

76: film layer

78: Planarized Surface

80: film layer

82: Planarized Surface

84: opening

86: Planarized Surface

88: GOG structure

90: Anisotropic conductive film

92: Conductive particles

94: bump clearance

96: Edge area

98: film layer

Detailed ways

According to the present invention, a gold bump structure 60 is shown in Figure 6A and Figure 6B, its top view is shown in Figure 7A and Figure 7B, Figure 6A is a cross-sectional view in the X direction, Figure 6B is in the Y direction sectional view. 6A and 6B, in the bump structure 60, the protective layer 64 with a planarized surface covers the bonding pad 62 of the substrate 12, the UBM 18 and the gold film 20 are stacked on the bonding pad 62 and the protective layer 64, and the gold bump Block 66 is on gold film 20 . The bonding pad 62 is made of aluminum, aluminum alloy, or other highly conductive metal or alloy. The protective layer 64 includes one or more layers of silicon dioxide, silicon nitride, or other highly chemically resistant materials or a combination thereof, to protect the circuitry in the underlying substrate 12 . UBM18 is mainly used to protect the bonding pad 62 to prevent various chemical molecules from invading the bonding pad 62 in the subsequent process to affect the electrical properties of the product, and at the same time improve the adhesion between the gold film 20 and the bonding pad 62. In one embodiment, the bonding pad 62 is made of aluminum , UBM18 contains titanium and tungsten, titanium is on the bottom layer, has a good co-junction with aluminum, and tungsten is on the top, and has a good co-junction with gold. As shown in FIG. 6A , the width w1x of the bonding pad 62 in the X direction is much smaller than that of known bonding pads, and the width w2x of the bump 66 in the X direction is also smaller, so the bump pitch p can be greatly reduced. However, in the Y direction, as shown in FIG. 6B , although the width w1y of the bond pad 62 is also smaller than that of known bond pads, the width w2y of the bump 66 is much larger than the width w1y of the bond pad 62 . Because the bonding pad 62 is smaller, the recessed area 68 in the center of the upper surface of the bump 66 shrinks even smaller, and the recessed area 68 can disappear completely if the UBM 18 is thicker. Since the protective layer 64 with a planarized surface is used, most of the upper surface of the bump 66 is a planarized area 70 , which can be used as an effective area during lamination. Unlike the known bump structure 10 , the active area 70 of the bump 66 is at the periphery of the upper surface rather than at the center, ie, the area mainly above the covering layer 64 .

FIG. 7A further shows the relationship of bump 66 to bond pad 62 . For comparison, the known bump 22 and bond pad 14 are also shown on the right side of FIG. 7A . In the known bump structure 10 , the bonding pad 14 is larger than the bump 22 , and the bonding pad 14 cannot be shrunk in order to obtain sufficient effective area of the bump 22 . However, in the bump structure 60 of the present invention, the bump 66 can be larger than the bonding pad 62, so the bonding pad 62 can be reduced as much as possible. In the bump structure 60 of the present invention, the contact surface 72 exposed by the bonding pad 62 for connecting the bump 66 has an elongated shape. But in the known bump structure 10 . The bonding pad 14 is exposed for the contact surface 74 of the connecting bump 22 to have a width close to that in the X and Y directions. FIG. 7B is a schematic diagram of forming high-density bumps 66 on the substrate 12 , and the bumps 66 are elongated and extend in the Y direction. In the X direction, since the bond pads 62 can be shrunk, the bumps 66 can be arranged more closely. If the planarized area 70 of the bumps 66 is to be increased, it can be achieved by increasing the width of the bumps 66 in the Y direction. Since the bonding pads 62 can be reduced, more bumps 66 can be accommodated in an IC of the same size, increasing the contact density and the number of pins of the IC.

8A to 8G are bump fabrication processes according to the present invention. In FIG. 8A , a film layer 76 such as silicon dioxide or silicon oxide is deposited to about 1000 to 1200 Angstroms over the bond pads 62 on the substrate 12 . The film layer 76 is etched back to a thickness of about 600 to 800 angstroms by, for example, chemical mechanical polishing, so that it has a planarized surface 78, as shown in FIG. 8B. In FIG. 8C , a layer 80 such as silicon nitride or silicon oxynitride is deposited at about 300 to 500 Angstroms on layer 76 , which also has a planarized surface 82 due to the planarized surface 78 of layer 76 . The film layers 76 and 80 are used as the protective layer 64 in FIG. 6A. Preferably, the material of the film layer 80 is harder than the film layer 76, and the softer film layer 76 is used to protect the surface of the substrate 12 and the bonding pad 62. The hard film layer 80 is used to resist external force. As shown in FIG. 8D , etching of the membrane layers 80 and 76 forms an opening 84 from the planarized surface 82 through the membrane layers 80 and 76 , exposing the contact surface 72 of the bonding pad 62 . In FIG. 8E, about 800 angstroms of titanium and tungsten are deposited as UBM18 on the contact surface 72 of the bonding pad 62 and the surface 82 of the film layer 80 by sputtering, and about 800 angstroms of gold film 20 is deposited on the UBM18 by sputtering. superior. As shown in FIG. 8F , the gold film 20 and the UBM 18 are patterned. In FIG. 8G, gold bumps 66 are grown from the gold film 20 by about 15 to 20 [mu]m by electroplating. Due to the formation of the protective layers 76 and 80 with planarized surfaces in the previous step, there is little or no depression 68 in the center of the upper surface of the bump 66 , mostly the planarized area 70 .

9A to 9D are another bump fabrication process according to the present invention. In FIG. 9A, film layers 76 and 80 are continuously deposited to cover the bonding pads 62 on the substrate 12. Preferably, the material of the film layer 80 is harder than the film layer 76, and the softer film layer 76 is used to protect the substrate 12 and the substrate 12. On the contact surface of the bonding pad 62, a harder film layer 80 is used to resist external forces. For example, the film layer 76 includes silicon dioxide or silicon oxide with a thickness of about 200 to 800 angstroms, and the film layer 80 includes silicon nitride or silicon oxynitride. The thickness is about 300 to 500 Angstroms. In FIG. 9B , etch back to a total thickness of about 600 to 1000 angstroms of the film layers 76 and 80 by, for example, chemical mechanical polishing, thereby forming a planarized surface 86 . In FIG. 9C , opening 84 is formed to expose contact surface 72 of bond pad 62 . In FIG. 9D, about 800 angstroms of titanium and tungsten are deposited as UBM18 on the contact surface 72 and the planarized surface 86 of the bonding pad 62 by sputtering, and a gold film 20 of about 800 angstroms is deposited on the UBM18 by sputtering. The gold film 20 and the UBM 18 are patterned, and gold bumps 66 are grown from the gold film 20 to a thickness of about 15 to 20 μm by electroplating. Due to the planarized surface 86 formed in the previous step, there is little or no depression 68 in the center of the upper surface of the bump 66 , mostly the planarized area 70 .

In the bump manufacturing process of the present invention, because the protective layer 64 with a planarized surface is used, the area of the UBM 18 on the planarized surface can be much larger than the area on the contact surface 72, resulting in a large effective area 70, Therefore, the bonding pad 62 can be made as small as possible.

Figure 10 shows a structure 88 for bonding the bump 66 to the wire 48 on the glass substrate 46. Unlike the known COG structure 44, the effective area of the bump 66 to provide the bonding is the planarized area 70, since there is no surface roughness Therefore, the particle size of the conductive particles 92 in the ACF90 has a large selection space, for example, 1 to 5 μm. Even if the conductive particles 92 with a smaller particle size are used, good conductive quality can still be obtained. Because the effective area is a planarized area 70 with a larger area, more conductive particles 92 can be captured in the effective area 70 during lamination. If conductive particles 92 with smaller particle diameters are used, more conductive particles will be captured. , better conductive quality. On the other hand, if the conductive particles 92 with a smaller particle size are used, the probability of short circuit or electric leakage due to the compression of the conductive particles 92 in the bump gap 94 is reduced. Furthermore, due to the use of the cover layer 64 with a planarized surface, the mechanical strength of the edge region 96 of the bump 66 is improved and cracking is less likely to occur. Since the protective layer 64 with a planarized surface is used in the bump structure 60, its thickness will not be limited. FIG. 11 is an example. The protective layer 64 includes film layers 76, 80 and 98. Silicon oxide or silicon oxide, the film layer 80 uses silicon nitride or silicon oxynitride, and the total thickness of the film layers 76, 80 and 98 is increased to more than 1.2 μm, thus increasing the mechanical strength.

Claims (36)

1. producing lug technology is used for forming a projection and is electrically connected to a joint sheet on a substrate, it is characterized in that this technology comprises the following steps:

Form one and have the sheath of a planarized surface to cover this joint sheet;

Form an opening and pass this sheath to expose a contact-making surface of this joint sheet; And

Form this projection on this planarized surface of this contact-making surface of this joint sheet and this sheath.

2. producing lug technology as claimed in claim 1 is characterized in that, the step that described formation one has the sheath of a planarized surface comprises the following steps:

Depositing one first rete covers on this joint sheet;

One surface of this first rete of planarization; And

Deposit one second rete on this first rete.

3. producing lug technology as claimed in claim 2 is characterized in that, described second rete comprises that at least one layer material is hard than this first rete.

4. producing lug technology as claimed in claim 2 is characterized in that, described first rete comprises silicon dioxide or silica, and this second rete comprises silicon nitride or silicon oxynitride.

5. producing lug technology as claimed in claim 2 is characterized in that, described first rete comprises silicon dioxide or silica, and described second rete comprises that one deck is silicon nitride or silicon oxynitride, and another layer is the lamination of silicon dioxide or silica.

6. producing lug technology as claimed in claim 2 is characterized in that, the step on a surface of this first rete of described planarization comprises this first rete of etch-back.

7. producing lug technology as claimed in claim 6 is characterized in that, the step of this first rete of described etch-back comprises this first rete of cmp.

8. producing lug technology as claimed in claim 1 is characterized in that, the step that described formation one has the sheath of a planarized surface comprises the following steps:

Depositing a lamination covers on this joint sheet; And

One surface of this lamination of planarization.

9. producing lug technology as claimed in claim 8 is characterized in that, described lamination comprises:

One first rete; And

One second rete is on this described first rete, and this second rete is hard than this first rete.

10. producing lug technology as claimed in claim 9 is characterized in that, described first rete comprises silicon dioxide or silica, and described second rete comprises silicon nitride or silicon oxynitride.

11. producing lug technology as claimed in claim 8 is characterized in that, described lamination comprises:

One first rete;

One second rete is on this first rete, and this second rete is hard than this first rete; And

One tertiary membrane layer is on this second rete, and this tertiary membrane layer is soft than this second rete.

12. producing lug technology as claimed in claim 11 is characterized in that, described first and the tertiary membrane layer comprise silicon dioxide or silica, described second rete comprises silicon nitride or silicon oxynitride.

13. producing lug technology as claimed in claim 8 is characterized in that, the step on a surface of described this lamination of planarization comprises this lamination of etch-back.

14. producing lug technology as claimed in claim 13 is characterized in that, the step of described this lamination of etch-back comprises this lamination of cmp.

15. producing lug technology as claimed in claim 1 is characterized in that, described opening has an elongated shape on this contact-making surface of this joint sheet.

16. producing lug technology as claimed in claim 1 is characterized in that, the step of this projection of described formation on this planarized surface of this contact-making surface of this joint sheet and this sheath comprises the following steps:

Form a projection underlying metal and have a second area having on this contact-making surface of this joint sheet on one first area and this planarized surface at this sheath, this second area is greater than this first area; And

Form a conductive projection and contact this projection underlying metal.

17. producing lug technology as claimed in claim 16 is characterized in that, the step that described formation one conductive projection contacts this projection underlying metal comprises the following steps:

Sputter one gold medal film is on this projection underlying metal; And

From this gold film gold medal projection of growing up.

18. producing lug technology as claimed in claim 1 is characterized in that, the step of this projection of described formation on this planarized surface of this contact-making surface of this joint sheet and this sheath comprises the following steps:

Form a projection underlying metal on this planarized surface of this contact-making surface of this joint sheet and this sheath; And

Form a conductive projection and contact this projection underlying metal, this conductive projection has the surface of a planarization at the opposite side with respect to this projection underlying metal.

19. producing lug technology as claimed in claim 18 is characterized in that, the step that described formation one conductive projection contacts this projection underlying metal comprises the following steps:

Sputter one gold medal film is on this projection underlying metal; And

From this gold film gold medal projection of growing up.

20. producing lug technology as claimed in claim 1 is characterized in that the area of described conductive projection is greater than the area of this joint sheet.

21. a projection cube structure is used for being electrically connected to the joint sheet on a substrate, it is characterized in that this projection cube structure comprises:

One sheath with a planarized surface covers the part of this joint sheet; And

One projection contacts the surface of this planarization of contact-making surface that this joint sheet do not cover by this sheath and this sheath.

22. projection cube structure as claimed in claim 21 is characterized in that, described sheath comprises:

One has first rete of a planarized surface; And

One second rete is on this first rete.

23. projection cube structure as claimed in claim 22 is characterized in that, described second rete comprises that at least one layer material is hard than this first rete.

24. projection cube structure as claimed in claim 22 is characterized in that, described first rete comprises silicon dioxide or silica, and described second rete comprises silicon nitride or silicon oxynitride.

25. projection cube structure as claimed in claim 22 is characterized in that, described first rete comprises silicon dioxide or silica, and described second rete comprises that one deck is silicon nitride or silicon oxynitride, and another layer is the lamination of silicon dioxide or silica.

26. projection cube structure as claimed in claim 21 is characterized in that, described sheath comprises:

One first rete; And

One has second rete of this planarized surface on this first rete.

27. projection cube structure as claimed in claim 26 is characterized in that, described second rete comprises that at least one layer material is hard than this first rete.

28. projection cube structure as claimed in claim 26 is characterized in that, described first rete comprises silicon dioxide or silica, and described second rete comprises silicon nitride or silicon oxynitride.

29. projection cube structure as claimed in claim 26 is characterized in that, described first rete comprises silicon dioxide or silica, and described second rete comprises that one deck is silicon nitride or silicon oxynitride, and another layer is the lamination of silicon dioxide or silica.

30. projection cube structure as claimed in claim 21 is characterized in that, described sheath comprises that two retes press from both sides a rete hard than this two rete.

31. projection cube structure as claimed in claim 21 is characterized in that, described joint sheet is not had an elongated shape by this contact-making surface that this sheath covers.

32. projection cube structure as claimed in claim 21 is characterized in that, described projection comprises:

One projection underlying metal has a second area having on this contact-making surface that is not covered by this sheath of this joint sheet on one first area and the surface in this planarization of this sheath, and this second area is greater than this first area; And

One conductive projection is on this projection underlying metal.

33. projection cube structure as claimed in claim 32 is characterized in that, described conductive projection comprises:

One gold medal film is on this projection underlying metal; And

One gold medal projection is on this gold film.

34. projection cube structure as claimed in claim 21 is characterized in that, described projection comprises:

One projection underlying metal is on the surface of this planarization of this contact-making surface that is not covered by this sheath of this joint sheet and this sheath; And

One conductive projection contacts this projection underlying metal, and this conductive projection has the surface of a planarization at the opposite side with respect to this projection underlying metal.

35. projection cube structure as claimed in claim 21 is characterized in that, the area of described conductive projection is greater than the area of this joint sheet.

36. a projection pressing structure is used for being electrically connected at a joint sheet and a lead on one second substrate on one first substrate, it is characterized in that this projection pressing structure comprises:

One sheath with a planarized surface covers the part of this joint sheet;

One projection contacts the surface of this planarization of contact-making surface that this joint sheet do not cover by this sheath and this sheath, and this projection has the surface of the surface of a planarization in the face of this planarization of this sheath; And

Between the surface and this lead of oppressed this planarization in this projection of many conducting particless.

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