Electrostatic protection device and forming method thereof, integrated circuit chip and forming method thereof

Abstract

The invention discloses an electrostatic protection device and a forming method thereof, and an integrated circuit chip and a forming method thereof. The forming method of the electrostatic protection device comprises the following steps: providing a substrate; forming a conductive contact structure on the substrate, wherein the step of forming the conductive contact structure comprises: forming an ion implantation region; forming a diffusion layer on the ion implantation region; forming a plurality of contact holes in the diffusion layer; forming a conductive substance in the contact hole, wherein the conductive substance is in conductive contact with the diffusion layer; and forming one or more grooves in the ion implantation region to improve the electrostatic protection performance. Through the one or more grooves, the contact area between the diffusion layer and the conductive substance can be increased, the contact resistance between the conductive substance and the diffusion layer is reduced, the electrostatic protection performance is further improved, and the device area is not additionally increased.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to an electrostatic protection device and a forming method thereof, an integrated circuit chip and a forming method thereof. Background Art

[0002] With the continuous improvement of semiconductor process technology, the size of semiconductor devices is shrinking. The harm of electrostatic discharge (ESD) to semiconductor integrated circuits has become more and more significant. And with the widespread use of semiconductor chips, there are more and more factors that cause semiconductor chips to be damaged by electrostatic discharge. According to statistics, 35% of the failed integrated circuit products are caused by electrostatic discharge problems. Therefore, in the existing chip design, the design of integrated circuit electrostatic protection devices has become particularly important.

[0003] At present, the design and application of electrostatic protection devices include: gate grounded N-type field effect transistor (GGNMOS) protection circuit, shallow trench isolation structure diode (STIdode) protection circuit, gate controlled diode (Gated diode) protection circuit, laterally diffused field effect transistor (Laterally Diffused MOS, LDMOS) protection circuit, bipolar junction transistor (BTT) protection circuit, etc.

[0004] However, as the size of semiconductor devices continues to decrease, the electrical performance of electrostatic protection devices in the prior art still needs to be improved. Summary of the invention

[0005] The technical problem solved by the present invention is to provide an electrostatic protection device and a method for forming the same, an integrated circuit chip and a method for forming the same, so as to improve the electrostatic protection performance without additionally increasing the device area.

[0006] To solve the above problems, the technical solution of the present invention provides a method for forming an electrostatic protection device, comprising: providing a substrate; forming a conductive contact structure on the substrate, wherein forming the conductive contact structure comprises: forming an ion implantation area; forming a diffusion layer on the ion implantation area; forming a plurality of contact holes on the diffusion layer; forming a conductive material in the contact hole, wherein the conductive material is in conductive contact with the diffusion layer; and further comprising: forming one or more grooves in the ion implantation area to improve the electrostatic protection performance.

[0007] Optionally, the ion implantation in the ion implantation area is performed after forming one or more of the grooves.

[0008] Optionally, the ion implantation region is an active region, and one or more grooves are formed in the active region.

[0009] Optionally, the method includes: forming a shallow isolation trench in the substrate; and forming one or more of the grooves and the shallow isolation trench simultaneously using the same mask.

[0010] Optionally, after one or more of the grooves are formed synchronously with the shallow isolation trenches, ion implantation is performed on the ion implantation area; and before the ion implantation, the method further includes: etching and removing the dielectric material in one or more of the grooves using a mask.

[0011] Optionally, the ion implantation in the ion implantation area includes: a first ion implantation and a second ion implantation, and one or more grooves are formed before the second ion implantation.

[0012] Optionally, the electrostatic protection device is a transistor, and the method for forming the electrostatic protection device further includes: forming a gate on the substrate; and forming one or more grooves after forming the gate and before the second ion implantation.

[0013] Optionally, the method further includes: forming a sidewall spacer on the sidewall of the gate; and forming the one or more grooves after the sidewall spacer is formed and before the second ion implantation is performed.

[0014] Optionally, the transistor includes a source region and a drain region corresponding to the ion implantation area; wherein, after forming the gate, the first ion implantation is performed on the source region and the drain region on both sides of the gate; after the first ion implantation is completed, the side wall is formed; after the side wall is formed, the second ion implantation is performed on the source region and the drain region; after the second ion implantation, a metal diffusion layer is formed on the source region and the drain region as the diffusion layer.

[0015] Optionally, the cross-sectional shape of one or more of the grooves is a combination of one or more of an inverted trapezoid, an inverted triangle, a semicircle, an ellipse, a rectangle and a polygon.

[0016] Optionally, the contact hole has a shape of an elongated strip and corresponds to a single target contact area, and the number of the contact hole is single or multiple.

[0017] Optionally, in a single target contact area, when there are multiple contact holes, the multiple contact holes are arranged in a row; when there is only one contact hole, the shape of the single contact hole is the long strip.

[0018] Optionally, the electrostatic protection device includes: a transistor, a diode or a resistor.

[0019] Optionally, the transistor includes: a substrate terminal, a gate terminal, a drain terminal and a source terminal; the contact holes include: a plurality of first sub-contact holes, a plurality of second sub-contact holes and a plurality of third sub-contact holes, the first sub-contact hole is formed on the drain terminal, the second sub-contact hole is formed on the source terminal, and the third sub-contact hole is formed on the substrate terminal; wherein at least one of the first sub-contact hole, the second sub-contact hole and the third sub-contact hole is in the shape of an elongated strip or has an area larger than the area of ​​the contact hole with the minimum characteristic size; the number of the first sub-contact holes, the second sub-contact holes and the third sub-contact holes is one or more respectively; and / or one or more of the first sub-contact holes, one or more of the second sub-contact holes, and one or more of the third sub-contact holes are arranged in a row respectively.

[0020] Optionally, the electrostatic protection device includes: a diode, the diode includes: a positive electrode and a negative electrode, the positive electrode surrounds the negative electrode; the plurality of contact holes include: a plurality of fourth sub-contact holes and a plurality of fifth sub-contact holes, the fourth sub-contact holes are formed on the positive electrode, and the fifth sub-contact holes are formed on the negative electrode; wherein at least one of the fourth sub-contact holes and the fifth sub-contact holes is in the shape of a long strip or has an area larger than the area of ​​a contact hole of a minimum characteristic size; the number of the plurality of fourth sub-contact holes and the plurality of fifth sub-contact holes are respectively one or more; and / or one or more of the fourth sub-contact holes and one or more of the fifth sub-contact holes are respectively formed in a row.

[0021] Optionally, when the number of the fifth sub-contact holes is one, the morphology of the fifth sub-contact hole matches the morphology of the negative electrode.

[0022] Optionally, the electrostatic protection device includes: a resistor, the resistor includes a positive electrode and a negative electrode; the plurality of contact holes include: a plurality of sixth sub-contact holes and a plurality of seventh sub-contact holes, the sixth sub-contact hole is formed on the positive electrode, and the seventh sub-contact hole is formed on the negative electrode; wherein at least one of the sixth sub-contact hole and the seventh sub-contact hole is in the shape of an elongated strip or has an area larger than the area of ​​a contact hole of a minimum characteristic size; the number of the plurality of sixth sub-contact holes and the plurality of seventh sub-contact holes is one or more respectively; and / or one or more of the sixth sub-contact holes and one or more of the seventh sub-contact holes are respectively formed in a row.

[0023] Optionally, the shapes of the contact holes include: a combination of one or more of a square, a strip, a circle and a polygon.

[0024] Correspondingly, the technical solution of the present invention further provides an electrostatic protection device, which is formed according to the method for forming an electrostatic protection device described in any of the above technical solutions.

[0025] Correspondingly, the technical solution of the present invention also provides a method for forming an integrated circuit chip, including forming an electrostatic protection device, wherein the electrostatic protection device is formed according to the method for forming an electrostatic protection device described in any of the above technical solutions.

[0026] Correspondingly, the technical solution of the present invention further provides an integrated circuit chip, characterized in that it is formed according to the method for forming an integrated circuit chip described in any of the above technical solutions.

[0027] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0028] In the method for forming an electrostatic protection device of the technical solution of the present invention, one or more grooves are formed in the ion implantation area. The one or more grooves can increase the contact area between the diffusion layer and the conductive material, reduce the contact resistance between the conductive material and the diffusion layer, and thus improve the electrostatic protection performance without increasing the device area.

[0029] Furthermore, the method further includes: forming a sidewall spacer on the sidewall of the gate; and forming the one or more grooves after the sidewall spacer is formed and before the second ion implantation. By forming the one or more grooves after the sidewall spacer is formed and before the second ion implantation, it is possible to effectively avoid affecting the process of other process steps during the formation of the one or more grooves.

[0030] Furthermore, the shape of the contact hole includes a strip shape, and corresponding to a single target contact area, the number of the contact holes is single or multiple. When the shape of the contact hole in a single target contact area is a strip shape, the contact area of ​​the contact hole can be effectively increased, the electrostatic protection performance is improved, and the device area will not be increased.

[0031] Furthermore, when the number of the fifth sub-contact holes is one, the morphology of the fifth sub-contact hole matches the morphology of the negative electrode. By matching the morphology of the fifth sub-contact hole with the morphology of the negative electrode, the area of ​​the fifth sub-contact hole can be maximized, thereby improving the electrostatic protection performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figures 1 to 3 is a schematic structural diagram of an electrostatic protection device in one embodiment of the present invention;

[0033] Figure 4 is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention;

[0034] Figure 5 is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention;

[0035] Figure 6 is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention;

[0036] Figure 7 is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention;

[0037] Figure 8 is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention;

[0038] Fig. 9 is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention;

[0039] Fig.10 is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention;

[0040] Fig.11 is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention;

[0041] Fig.12 is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention;

[0042] Fig.13 is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention;

[0043] Fig.14 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention. DETAILED DESCRIPTION

[0044] As described in the background art, the electrical performance of the electrostatic protection device in the prior art still needs to be improved, which will be described in detail below.

[0045] At present, the failure modes of ESD protection devices usually include: thermal failure caused by high current and oxide layer breakdown caused by high field strength. Thermal failure often occurs in the PN junction, channel and metal connection of the discharge path in ESD protection devices. Among them, the contact position between the conductive material and the device layer in the metal connection is a more common failure position, which is mostly caused by excessive current flowing through the conductive material.

[0046] The process of the diffusion layer (i.e., metal silicide layer) in the chip is used to reduce the contact resistance between the conductive material and the device layer, thereby increasing the operating speed of the internal circuit. The conductive material is generally formed on the diffusion layer and connected to the device layer through the diffusion layer. Due to the problem of uneven diffusion during the formation of the diffusion layer, there is a difference in resistance between the conductive material and the device layer at different positions, and there may also be a difference in resistance at different positions of the same diffusion layer. The difference in resistance causes different currents flowing through different positions, and positions with large currents are more likely to experience thermal failures, which makes it more likely to cause failure of the electrostatic protection device.

[0047] In the prior art, in order to solve the problem that the conductive material becomes a weak point and is burned through, thereby causing the performance failure of the electrostatic protection device, the contact area is usually increased by increasing the number of conductive materials, for example, from a single row of conductive materials to multiple rows of conductive materials, or by increasing the area of ​​the device layer to increase the strength of the contact point. However, these solutions are not conducive to saving the area of ​​the device.

[0048] On this basis, the present invention provides an electrostatic protection device and a method for forming the same, an integrated circuit chip and a method for forming the same, wherein one or more grooves are formed in the ion implantation area, and the contact area between the diffusion layer and the conductive material can be increased through the one or more grooves, and the contact resistance between the conductive material and the diffusion layer can be reduced, thereby improving the electrostatic protection performance without increasing the device area.

[0049] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0050] Figures 1 to 3 It is a schematic structural diagram of an electrostatic protection device in one embodiment of the present invention.

[0051] Please refer to Figures 1 to 3 , Figure 2 yes Figure 1 Schematic diagram of the cross section along line AA, Figure 3 yes Figure 1 The cross-sectional schematic diagram along line BB in the figure shows a method for forming an electrostatic protection device, comprising: providing a substrate 100; forming a conductive contact structure on the substrate 100, wherein forming the conductive contact structure comprises: forming an ion implantation region 101; forming a diffusion layer 102 on the ion implantation region 101; forming a plurality of contact holes (not shown) on the diffusion layer 102; forming a conductive material 103 in the contact hole, wherein the conductive material 103 is in conductive contact with the diffusion layer 102; and forming one or more grooves 104 in the ion implantation region 101 to improve the electrostatic protection performance.

[0052] In this embodiment, the diffusion layer 102 is formed on the bottom and sidewall surface of one or more grooves 104, and the conductive material 103 is formed on the diffusion layer 102 and fills the one or more grooves 104. The one or more grooves 104 can increase the contact area between the diffusion layer 102 and the conductive material 103, reduce the contact resistance between the conductive material 103 and the diffusion layer 102, and thus improve the electrostatic protection performance without increasing the device area.

[0053] In this embodiment, the ion implantation in the ion implantation region 101 is performed after forming one or more grooves 104 .

[0054] In this embodiment, the ion implantation region 101 is an active region, and one or more grooves 104 are formed in the active region.

[0055] In this embodiment, the ion implantation of the ion implantation region 101 includes: a first ion implantation and a second ion implantation, and one or more grooves 104 are formed before the second ion implantation.

[0056] In this embodiment, the electrostatic protection device is a transistor, and the method for forming the electrostatic protection device further includes: forming a gate 105 on the substrate 100 ; and forming a sidewall 106 on the sidewall of the gate 105 .

[0057] In this embodiment, the transistor includes a source region and a drain region corresponding to the ion implantation area 101; wherein, after the gate 105 is formed, the first ion implantation is performed on the source region and the drain region on both sides of the gate 105; after the first ion implantation is completed, the side wall 106 is formed; after the side wall 106 is formed, the second ion implantation is performed on the source region and the drain region; after the second ion implantation, a metal diffusion layer is formed on the source region and the drain region as the diffusion layer 102.

[0058] In this embodiment, the one or more grooves 104 are formed after the sidewall 106 is formed and before the second ion implantation is performed. By forming the one or more grooves 104 after the sidewall 106 is formed and before the second ion implantation is performed, it is possible to effectively avoid affecting other process steps (such as the gate process step) during the process of forming the one or more grooves 104.

[0059] In other embodiments, one or more recesses are formed after forming the gate and before the second ion implantation is performed.

[0060] In this embodiment, before the first ion implantation is performed, the process further includes: forming a shallow isolation trench in the substrate 100 ; and filling the shallow isolation trench with a dielectric material 107 .

[0061] In other embodiments, one or more of the grooves may be formed simultaneously with the shallow isolation grooves using the same mask; after one or more of the grooves are formed synchronously with the shallow isolation grooves, ion implantation is performed on the ion implantation area. It should be noted that before the ion implantation, it also includes: etching away the dielectric material in one or more of the grooves using a mask. This is because in the process of filling the dielectric material using a global process, the dielectric material will also be filled synchronously in one or more of the grooves, so it is necessary to etch away the dielectric material in one or more of the grooves before the ion implantation.

[0062] In this embodiment, the cross-sectional shape of one or more of the grooves 104 is a combination of one or more of an inverted trapezoid, an inverted triangle, a semicircle, an ellipse, a rectangle and a polygon.

[0063] Figure 4 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0064] In this embodiment, in the above embodiment ( Figures 1 to 3 ) is used to continue to describe the electrostatic protection device, and the rest are the same, except that: the shape of the contact hole includes a long strip, and corresponding to a single target contact area, the number of the contact holes is single or multiple. Pulling multiple small-sized contact holes to form a long strip hole, or directly expanding the size of a single small-sized contact hole to a long strip, can further increase the contact area between the diffusion layer and the conductive material, further reduce the contact resistance between the conductive material and the diffusion layer, and thus improve the electrostatic protection performance, without additionally increasing the device area. The following will be specifically described in conjunction with the accompanying drawings.

[0065] Please refer to Figure 4 The shape of the contact hole includes a long strip, and corresponds to a single target contact area, and the number of the contact holes is single or multiple.

[0066] In this embodiment, in a single target contact area, when the number of the contact holes is multiple, the multiple contact holes are arranged in a row (i.e., the first direction X in the figure); when the number of the contact hole is single, the morphology of the single contact hole is the long strip.

[0067] Please continue to refer to Figure 4In this embodiment, the electrostatic protection device is a transistor, and the transistor includes: a substrate terminal 200, a gate terminal 201, a drain terminal 202 and a source terminal 203; the contact hole includes: a plurality of first sub-contact holes 204, a plurality of second sub-contact holes 205 and a plurality of third sub-contact holes 206, wherein the first sub-contact hole 204 is located on the drain terminal 202, the second sub-contact hole 205 is located on the source terminal 203, and the third sub-contact hole 206 is located on the substrate terminal 200; wherein at least one of the first sub-contact hole 204, the second sub-contact hole 205 and the third sub-contact hole 206 is in a strip shape or has an area greater than that of a contact hole with a minimum characteristic size; the number of the plurality of the first sub-contact holes 204, the plurality of the second sub-contact holes 205 and the plurality of the third sub-contact holes 206 is one or more respectively; and / or one or more of the first sub-contact holes 204, one or more of the second sub-contact holes 205, and one or more of the third sub-contact holes 206 are arranged in a row respectively.

[0068] In this embodiment, the first sub-contact hole 204 has a first sub-projection area size, the second sub-contact hole 205 has a second sub-projection area size, and the third sub-contact hole 206 has a third sub-projection area size.

[0069] In this embodiment, the first sub-projection area size is larger than the second sub-projection area size and the third sub-projection area size, and the number of the first sub-contact holes 204 is smaller than the number of the second sub-contact holes 205 and the number of the third sub-contact holes 206.

[0070] In this embodiment, there are multiple first sub-contact holes 204 .

[0071] In this embodiment, there are multiple second sub-contact holes 205 , which are arranged along the first direction X. The multiple second sub-contact holes 205 have opposite first ends 205 a and second ends 205 b along the first direction X.

[0072] In this embodiment, a plurality of the first sub-contact holes 204 are arranged along the first direction X, and a plurality of the first sub-contact holes 204 have a third end 204a and a fourth end 204b opposite to each other; along the second direction Y, the third end 204a is flush with the first end 205a, and the fourth end 204b is flush with the second end 205b, and the first direction X is perpendicular to the second direction Y.

[0073] In this embodiment, the number of the second sub-contact holes 205 and the number of the third sub-contact holes 206 are the same, and are both greater than the number of the first sub-contact holes 204 .

[0074] In this embodiment, the plurality of third sub-contact holes 206 are arranged along the first direction X, and some of the third sub-contact holes 206 have opposite fifth ends 206a and sixth ends 206b; along the second direction Y, the fifth end 206a is flush with the first end 205a, and the sixth end 206b is flush with the second end 205b.

[0075] In this embodiment, the shapes of the first sub-contact hole 204, the second sub-contact hole 205 and the third sub-contact hole 206 are all squares, wherein the morphological side lengths of the first sub-contact hole 204 are respectively greater than the morphological side lengths of the second sub-contact hole 205 and the third sub-contact hole 206, that is, the areas of the second sub-contact hole 205 and the third sub-contact hole 206 are the areas of the contact holes with the minimum characteristic size, and the area of ​​the first sub-contact hole 204 is greater than the area of ​​the contact hole with the minimum characteristic size.

[0076] Figure 5 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0077] In this embodiment, in the above embodiment ( Figure 4 ), the electrostatic protection device is further described based on the above, and the rest are the same, except that: the shape of the first sub-contact hole 204 is a long strip. The following will be described in detail with reference to the accompanying drawings.

[0078] Please refer to Figure 5 , the first sub-contact hole 204 is in the shape of a long strip.

[0079] In this embodiment, the long side of the first sub-contact hole 204 is greater than the side lengths of the second sub-contact hole 205 and the third sub-contact hole 206, and the wide side of the first sub-contact hole 204 is greater than or equal to the side lengths of the second sub-contact hole 205 and the third sub-contact hole 206.

[0080] In other embodiments, the shapes of some of the contact holes may be circular or polygonal; or the shapes of some of the contact holes may be a combination of square, strip, circular and polygonal.

[0081] Figure 6 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0082] In this embodiment, in the above embodiment ( Figure 4 ), the electrostatic protection device is further described based on the above, and the rest are the same, except that: the number of the first sub-contact hole 204 is one. The following will be described in detail with reference to the accompanying drawings.

[0083] Please refer to Figure 6 , the number of the first sub-contact hole 204 is one.

[0084] In this embodiment, the first sub-contact hole 204 extends along the first direction X, and has a third end 204a and a fourth end 204b opposite to each other; along the second direction Y, the third end 204a is flush with the first end 205a, and the fourth end 204b is flush with the second end 205b.

[0085] In this embodiment, the first sub-contact hole 204 is in a strip shape.

[0086] Figure 7 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0087] In this embodiment, in the above embodiment ( Figure 4 ), the electrostatic protection device is further described based on the above, and the rest are the same, except that: the third sub-projection area size is larger than the first sub-projection area size and the second sub-projection area size, and the number of the third sub-contact holes 206 is smaller than the number of the first sub-contact holes 204 and the number of the second sub-contact holes 205. The following will be described in detail with reference to the accompanying drawings.

[0088] Please refer to Figure 7 , the third sub-projection area size is larger than the first sub-projection area size and the second sub-projection area size, and the number of the third sub-contact holes 206 is smaller than the number of the first sub-contact holes 204 and the number of the second sub-contact holes 205.

[0089] In this embodiment, there are multiple third sub-contact holes 206 .

[0090] In other embodiments, the number of the third sub-contact hole may also be one.

[0091] In this embodiment, the third sub-contact hole 206 is in a square shape, and the first sub-contact hole 204 and the second sub-contact hole 205 are also in a square shape. The morphological side length of the third sub-contact hole 206 is respectively greater than the morphological side lengths of the first sub-contact hole 204 and the second sub-contact hole 205, that is, the area of ​​the first sub-contact hole 204 and the second sub-contact hole 205 is the area of ​​the minimum characteristic size contact hole, and the area of ​​the third sub-contact hole 206 is greater than the area of ​​the minimum characteristic size contact hole.

[0092] In other embodiments, the shapes of some of the third sub-contact holes may be strips, circles or polygons; or the shapes of some of the third sub-contact holes may be a combination of squares, strips, circles and polygons.

[0093] In other embodiments, when the number of the third sub-contact holes is one, the third sub-contact hole extends along the first direction, and the third sub-contact hole has a fifth end and a sixth end relative to each other; along the second direction, the fifth end is flush with the first end, and the sixth end is flush with the second end.

[0094] Figure 8 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0095] In this embodiment, in the above embodiment ( Figure 4 ), the electrostatic protection device is further described based on the above, and the rest are the same, except that: the first sub-projection area size and the third sub-projection area size are respectively larger than the second sub-projection area size, and the number of the first sub-contact hole 204 and the third sub-contact hole 206 are respectively smaller than the number of the second sub-contact hole 205. The following will be described in detail with reference to the accompanying drawings.

[0096] Please refer to Figure 8 , the first sub-projection area size and the third sub-projection area size are respectively larger than the second sub-projection area size, and the number of the first sub-contact holes 204 and the third sub-contact holes 206 are respectively smaller than the number of the second sub-contact holes 205.

[0097] In this embodiment, the number of the first sub-contact holes 204 is plural, and the number of the third sub-contact holes 206 is plural.

[0098] In other embodiments, the number of the first sub-contact hole may be one, and the number of the third sub-contact hole may be one.

[0099] In this embodiment, the shapes of the first sub-contact hole 204, the second sub-contact hole 205 and the third sub-contact hole 206 are all square. The morphological side lengths of the first sub-contact hole 204 and the third sub-contact hole 206 are respectively greater than the morphological side lengths of the second sub-contact hole 205, that is, the area of ​​the second sub-contact hole 205 is the area of ​​the minimum characteristic size contact hole, and the areas of the first sub-contact hole 204 and the third sub-contact hole 206 are respectively greater than the area of ​​the minimum characteristic size contact hole.

[0100] In other embodiments, the shapes of the first sub-contact holes may be strips, circles or polygons; or the shapes of the first sub-contact holes may be a combination of squares, strips, circles and polygons. The shapes of the third sub-contact holes may be strips, circles or polygons; or the shapes of the third sub-contact holes may be a combination of squares, strips, circles and polygons.

[0101] In other embodiments, the shapes of the first sub-contact holes may be strips, circles or polygons; or the shapes of the first sub-contact holes may be a combination of squares, strips, circles and polygons. The shapes of the third sub-contact holes may be strips, circles or polygons; or the shapes of the third sub-contact holes may be a combination of squares, strips, circles and polygons.

[0102] Fig. 9 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0103] In this embodiment, in the above embodiment ( Figure 4 ) is continued to describe the electrostatic protection device, and the rest are the same, except that: the electrostatic protection device includes: a diode. The following will be specifically described in conjunction with the accompanying drawings.

[0104] Please refer to Fig. 9 , the electrostatic protection device includes: a diode, the diode includes: an anode 300 and a cathode 301, the anode 300 surrounds the cathode 301; the plurality of contact holes include: a plurality of fourth sub-contact holes 302 and a plurality of fifth sub-contact holes 303, the fourth sub-contact hole 302 is located on the anode 300, and the fifth sub-contact hole 303 is located on the cathode 301; wherein, at least one of the fourth sub-contact hole 302 and the fifth sub-contact hole 303 is in the shape of a strip or has an area larger than that of a contact hole with a minimum characteristic size; the number of the plurality of fourth sub-contact holes 302 and the number of the plurality of fifth sub-contact holes 303 are respectively one or more; and / or one or more of the fourth sub-contact holes 302 and one or more of the fifth sub-contact holes 303 are respectively formed in a row (i.e., the first direction X in the figure).

[0105] In this embodiment, the number of the fourth sub-contact holes 302 is plural, and the fourth sub-contact holes 302 include: a first contact hole group 302A and a second contact hole group 302B.

[0106] In this embodiment, there are multiple fourth sub-contact holes 302 in the first contact hole group 302A and the second contact hole group 302B, and the multiple fourth sub-contact holes 302 are arranged in a strip shape along the direction in which the positive electrode 300 extends (i.e., the first direction X in the figure).

[0107] In this embodiment, the number of the fifth sub-contact holes 303 is plural, and the fifth sub-contact holes 303 are arranged in a strip shape along the direction in which the negative electrode 301 extends in length (ie, the first direction X in the figure).

[0108] In this embodiment, a plurality of the fifth sub-contact holes 303 are located between the first contact hole group 302A and the second contact hole group 302B.

[0109] In this embodiment, the areas of the fourth sub-contact hole 302 and the fifth sub-contact hole 303 are respectively larger than the area of ​​the contact hole with the minimum characteristic size.

[0110] Fig.10 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0111] In this embodiment, in the above embodiment ( Fig. 9 ), the electrostatic protection device is further described based on the above, and the rest are the same, except that: the number of the fourth sub-contact holes 302 in the first contact hole group 302A and the second contact hole group 302B is one; the number of the fifth sub-contact holes 303 is one. The following will be described in detail with reference to the accompanying drawings.

[0112] Please refer to Fig.10 , the number of the fourth sub-contact holes 302 in the first contact hole group 302A and the second contact hole group 302B is one; the number of the fifth sub-contact holes 303 is one.

[0113] In this embodiment, the fourth sub-contact hole 302 extends in a strip shape along the direction in which the positive electrode 300 extends in length, that is, the fourth sub-contact hole 302 is in a strip shape.

[0114] In this embodiment, the fifth sub-contact hole 303 extends in a strip shape along the direction in which the negative electrode 301 extends in length, that is, the fifth sub-contact hole 303 is in a strip shape.

[0115] Fig.11 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0116] In this embodiment, in the above embodiment ( Fig.10), the electrostatic protection device is further described based on the above, and the rest are the same, except that the morphology of the fifth sub-contact hole 303 matches the morphology of the negative electrode 301. The following will be described in detail with reference to the accompanying drawings.

[0117] Please refer to Fig.11 , the morphology of the fifth sub-contact hole 303 matches the morphology of the negative electrode 301 .

[0118] In this embodiment, by matching the morphology of the fifth sub-contact hole 303 with the morphology of the negative electrode 301 , the area of ​​the fifth sub-contact hole 303 can be maximized, thereby improving the electrical performance of the electrostatic protection device.

[0119] Fig.12 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0120] In this embodiment, in the above embodiment ( Fig.11 ), the electrostatic protection device is further described based on the above, and the rest are the same, except that: the number of the fourth sub-contact holes 302 is multiple, and the fourth sub-contact holes 302 include: a first contact hole group 302A, a second contact hole group 302B, a third contact hole group 302C and a fourth contact hole group 302D. The following will be specifically described in conjunction with the accompanying drawings.

[0121] Please refer to Fig.12 The number of the fourth sub-contact holes 302 is multiple, and the fourth sub-contact holes 302 include: a first contact hole group 302A, a second contact hole group 302B, a third contact hole group 302C and a fourth contact hole group 302D.

[0122] In this embodiment, the number of the fourth sub-contact hole 302 in the first contact hole group 302A, the second contact hole group 302B, the third contact hole group 302C and the fourth contact hole 302D is one, the fourth sub-contact hole 302 in the contact hole group 302A and the second contact hole group 302B extends in a long strip shape along the direction in which the positive electrode 300 extends in length (i.e., in the first direction Y in the figure), and the fourth sub-contact hole 302 in the third contact hole group 302C and the fourth contact hole group 302D extends in a long strip shape along the direction in which the positive electrode 300 extends in width (i.e., in the second direction Y in the figure).

[0123] In other embodiments, when the number of the fourth sub-contact holes in the first contact hole group, the second contact hole group, the third contact hole group, and the fourth contact hole is multiple, the multiple fourth sub-contact holes in the contact hole group and the second contact hole group are arranged in long strips along the direction in which the positive electrode extends in length, and the multiple fourth sub-contact holes in the third contact hole group and the fourth contact hole group are arranged in long strips along the direction in which the positive electrode extends in width.

[0124] In this embodiment, the number of the plurality of fifth sub-contact holes 303 is one, and the fifth sub-contact hole 303 extends in a strip shape along the direction in which the negative electrode 301 extends.

[0125] In other embodiments, when the number of the fifth sub-contact holes is plural, the plurality of the fifth sub-contact holes are arranged in a strip shape along the direction in which the length of the negative electrode extends.

[0126] In this embodiment, the plurality of fifth sub-contact holes 303 are respectively located between the first contact hole group 302A and the second contact hole group 302B, and between the third contact hole group 302C and the fourth contact hole group 302D.

[0127] Fig.13 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0128] In this embodiment, in the above embodiment ( Figure 4 ) is continued to describe the electrostatic protection device, and the rest are the same, except that: the electrostatic protection device includes: a resistor. The following will be specifically described in conjunction with the accompanying drawings.

[0129] Please refer to Fig.13 , the electrostatic protection device includes: a resistor, the resistor includes a positive electrode 400 and a negative electrode 401; the plurality of contact holes include: a plurality of sixth sub-contact holes 402 and a plurality of seventh sub-contact holes 403, the sixth sub-contact hole 402 is located on the positive electrode 400, and the seventh sub-contact hole 403 is located on the negative electrode 401; wherein, at least one of the sixth sub-contact hole 402 and the seventh sub-contact hole 403 is in a strip shape or has an area larger than the area of ​​the minimum characteristic size contact hole; the number of the plurality of the sixth sub-contact holes 402 and the plurality of the seventh sub-contact holes 403 are respectively one or more; and / or one or more of the sixth sub-contact holes 402 and one or more of the seventh sub-contact holes 403 are respectively formed in a row (i.e., the first direction X in the figure).

[0130] In this embodiment, the number of the sixth sub-contact holes 402 is plural, and the plurality of the sixth sub-contact holes 402 are arranged in a strip shape along the direction in which the length of the positive electrode 300 extends (ie, the first direction X in the figure).

[0131] In this embodiment, the number of the seventh sub-contact holes 403 is plural, and the plurality of the seventh sub-contact holes 403 are arranged in a strip shape along the direction in which the negative electrode 401 extends in length (ie, the first direction X in the figure).

[0132] In this embodiment, the areas of the sixth sub-contact hole 402 and the seventh sub-contact hole 403 are respectively larger than the area of ​​the contact hole with the minimum characteristic size.

[0133] Fig.14 It is a schematic structural diagram of an electrostatic protection device in another embodiment of the present invention.

[0134] In this embodiment, in the above embodiment ( Fig.13 ), the electrostatic protection device is further described based on the above, and the rest are the same, except that: the number of the plurality of sixth sub-contact holes 402 is one; the number of the plurality of seventh sub-contact holes 403 is one. The following will be described in detail with reference to the accompanying drawings.

[0135] Please refer to Fig.14 , the number of the plurality of sixth sub-contact holes 402 is one; the number of the plurality of seventh sub-contact holes 403 is one.

[0136] In this embodiment, the sixth sub-contact hole 402 extends in a strip shape along the direction in which the positive electrode 300 extends in length, that is, the sixth sub-contact hole 402 is in a strip shape.

[0137] In this embodiment, the seventh sub-contact hole 403 extends in a strip shape along the direction in which the negative electrode 401 extends in length, that is, the seventh sub-contact hole 403 is in a strip shape.

[0138] Correspondingly, an embodiment of the present invention further provides an electrostatic protection device, which is formed according to the method for forming an electrostatic protection device described in any of the above embodiments.

[0139] Correspondingly, an embodiment of the present invention further provides a method for forming an integrated circuit chip, including forming an electrostatic protection device, wherein the electrostatic protection device is formed according to the method for forming an electrostatic protection device described in any of the above embodiments.

[0140] Correspondingly, an embodiment of the present invention further provides an integrated circuit chip, which is formed according to the above-mentioned method for forming an integrated circuit chip.

[0141] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A method for forming an electrostatic protection device, comprising: providing a substrate; A conductive contact structure is formed on the substrate, wherein forming the conductive contact structure comprises: forming an ion implantation region; forming a diffusion layer on the ion implantation region; forming a plurality of contact holes on the diffusion layer; forming a conductive material in the contact hole, wherein the conductive material is in conductive contact with the diffusion layer; It is characterized by further comprising: One or more grooves are formed in the ion implantation region to improve electrostatic protection performance.

2. The method for forming an electrostatic protection device according to claim 1, wherein: The ion implantation in the ion implantation region is performed after forming one or more grooves.

3. The method for forming an electrostatic protection device according to claim 1 or 2, characterized in that: The ion implantation region is an active region, and one or more grooves are formed in the active region.

4. The method for forming an electrostatic protection device according to claim 1, wherein: Also includes: forming a shallow isolation trench in the substrate; One or more of the recesses and the shallow isolation trenches are formed simultaneously using the same mask.

5. The method for forming an electrostatic protection device according to claim 4, characterized in that: After forming one or more of the grooves synchronously with the shallow isolation trenches, ion implantation is performed on the ion implantation area; before the ion implantation, the method further includes: etching and removing the dielectric material in one or more of the grooves using a mask.

6. The method for forming an electrostatic protection device according to any one of claims 1 to 5, characterized in that: The ion implantation in the ion implantation region includes: a first ion implantation and a second ion implantation, and one or more grooves are formed before the second ion implantation.

7. The method for forming an electrostatic protection device according to claim 6, wherein: The electrostatic protection device is a transistor, and the method for forming the electrostatic protection device further includes: forming a gate on the substrate; and forming one or more grooves after forming the gate and before the second ion implantation.

8. The method for forming an electrostatic protection device according to claim 7, wherein: Also includes: A sidewall spacer is formed on the sidewall of the gate; and the one or more grooves are formed after the sidewall spacer is formed and before the second ion implantation is performed.

9. The method for forming an electrostatic protection device according to claim 8, characterized in that: The transistor includes a source region and a drain region corresponding to the ion implantation area; wherein, after the gate is formed, the first ion implantation is performed on the source region and the drain region on both sides of the gate; after the first ion implantation is completed, the side wall is formed; after the side wall is formed, the second ion implantation is performed on the source region and the drain region; after the second ion implantation, a metal diffusion layer is formed on the source region and the drain region as the diffusion layer.

10. The method for forming an electrostatic protection device according to claim 1, wherein: The cross-sectional shape of one or more of the grooves is a combination of one or more of an inverted trapezoid, an inverted triangle, a semicircle, an ellipse, a rectangle and a polygon.

11. The method for forming an electrostatic protection device according to claim 1, wherein: The contact hole has a shape of a long strip and corresponds to a single target contact area. The number of the contact hole is single or multiple.

12. The method for forming an electrostatic protection device according to claim 11, wherein: In a single target contact area, when there are multiple contact holes, the multiple contact holes are arranged in a row; when there is only one contact hole, the shape of the single contact hole is the long strip.

13. The method for forming an electrostatic protection device according to claim 11 or 12, characterized in that: The electrostatic protection device includes: a transistor, a diode or a resistor.

14. The method for forming an electrostatic protection device according to claim 13, wherein: The transistor comprises: a substrate terminal, a gate terminal, a drain terminal and a source terminal; the plurality of contact holes comprises: a plurality of first sub-contact holes, a plurality of second sub-contact holes and a plurality of third sub-contact holes, wherein the first sub-contact hole is formed on the drain terminal, the second sub-contact hole is formed on the source terminal, and the third sub-contact hole is formed on the substrate terminal; wherein, At least one of the first sub-contact hole, the second sub-contact hole and the third sub-contact hole is in a strip shape or has an area larger than that of the contact hole with the minimum characteristic size; The number of the first sub-contact holes, the number of the second sub-contact holes and the number of the third sub-contact holes are respectively one or more; And / or one or more of the first sub-contact holes, one or more of the second sub-contact holes, and one or more of the third sub-contact holes are arranged in a row respectively.

15. The method for forming an electrostatic protection device according to claim 13, wherein: The electrostatic protection device comprises: a diode, the diode comprises: an anode and a cathode, the anode surrounds the cathode; the plurality of contact holes comprises: a plurality of fourth sub-contact holes and a plurality of fifth sub-contact holes, the fourth sub-contact hole is formed on the anode, and the fifth sub-contact hole is formed on the cathode; wherein, At least one of the fourth sub-contact hole and the fifth sub-contact hole is in a strip shape or has an area larger than that of the contact hole with the minimum characteristic size; The number of the plurality of fourth sub-contact holes and the number of the plurality of fifth sub-contact holes are respectively one or more; And / or one or more of the fourth sub-contact holes and one or more of the fifth sub-contact holes are respectively formed in a row.

16. The method for forming an electrostatic protection device according to claim 15, wherein: When the number of the fifth sub-contact holes is one, the morphology of the fifth sub-contact hole matches the morphology of the negative electrode.

17. The method for forming an electrostatic protection device according to claim 13, wherein: The electrostatic protection device The invention comprises: a resistor, wherein the resistor comprises a positive electrode and a negative electrode; the plurality of contact holes comprises: a plurality of sixth sub-contact holes and a plurality of seventh sub-contact holes, wherein the sixth sub-contact hole is formed on the positive electrode, and the seventh sub-contact hole is formed on the negative electrode; wherein, At least one of the sixth sub-contact hole and the seventh sub-contact hole is in a strip shape or has an area larger than that of the contact hole with the minimum characteristic size; The number of the plurality of sixth sub-contact holes and the number of the plurality of seventh sub-contact holes are respectively one or more; And / or one or more of the sixth sub-contact holes and one or more of the seventh sub-contact holes are respectively formed in a row.

18. The method for forming an electrostatic protection device according to claim 1, wherein: The shapes of the contact holes include: a square, a strip, a circle, and a polygon, or a combination of one or more of the above.

19. An electrostatic protection device, characterized in that: The electrostatic protection device is formed according to the method for forming the electrostatic protection device according to any one of claims 1 to 18.

20. A method for forming an integrated circuit chip, characterized in that: The method comprises forming an electrostatic protection device, wherein the electrostatic protection device is formed according to the method for forming an electrostatic protection device according to any one of claims 1 to 18.

21. An integrated circuit chip, characterized in that: The method for forming an integrated circuit chip according to claim 20.

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