SEMICONDUCTOR DEVICE AND METHOD FOR FORMING THE SAME
20250234614 ยท 2025-07-17
Assignee
Inventors
Cpc classification
International classification
H01L29/66
ELECTRICITY
H01L29/06
ELECTRICITY
H01L29/08
ELECTRICITY
Abstract
Provided are a semiconductor device and a method for forming the same. The semiconductor device includes a substrate including first and second active regions defined by an element isolation structure, a first element in the first active region and including a gate structure on the substrate, a second element in the second active region and including an insulation pattern in the substrate and including a first portion and a second portion surrounding the first portion, and a dummy gate structure in the second active region and including first and second patterns respectively on the first and second portions and a third pattern on the device isolation structure. The second portion and the element isolation structure define a region where a first doped region of the second element is formed. The second portion and the first portion define a region where a second doped region of the second element is formed.
Claims
1. A semiconductor device, comprising: a substrate comprising a first active region and a second active region defined by an element isolation structure; a first element disposed in the first active region and comprising a gate structure disposed on the substrate and source/drain regions disposed in the first active region at opposite sides of the gate structure; a second element disposed in the second active region and comprising an insulation pattern embedded in the substrate and a first doped region and second doped regions in the substrate, wherein the insulation pattern comprises a first portion and a second portion surrounding the first portion, the second portion and the element isolation structure define a region in the second active region where the first doped region is formed therein, and the second portion and the first portion define a region in the second active region where the second doped regions are formed therein; and a dummy gate structure disposed in the second active region and comprising a first pattern disposed on the first portion of the insulation pattern, a second pattern disposed on the second portion of the insulation pattern, and a third pattern disposed on the element isolation structure.
2. The semiconductor device of claim 1, wherein the gate structure comprises a first high dielectric constant layer, a first capping layer and a first metal gate disposed on the substrate sequentially, and the dummy gate structure comprises a second high dielectric constant layer, a second capping layer and a second metal gate disposed on the substrate sequentially, and the first metal gate and the second metal gate are disposed at the same level height respective to the substrate.
3. The semiconductor device of claim 1, wherein the first pattern comprises annular patterns, dot patterns, or strip patterns arranged in a first direction and extending in a second direction.
4. The semiconductor device of claim 3, wherein the second doped regions of the second element extend in the first direction and are spaced apart from each other in the second direction.
5. The semiconductor device of claim 4, wherein the first doped region of the second element surrounds the insulation pattern and has a conductivity type different from the second doped regions.
6. The semiconductor device of claim 1, further comprising: a first dielectric structure disposed between the first pattern and the second pattern of the dummy gate structure above the insulation pattern; and a second dielectric structure disposed between the second pattern and the third pattern of the dummy gate structure above the insulation pattern, wherein the first dielectric structure and the second dielectric structure are spaced apart from each other.
7. The semiconductor device of claim 6, wherein the first dielectric structure covers the second doped regions, and the second dielectric structure covers the first doped region.
8. The semiconductor device of claim 1, wherein the substrate comprises: a first well region disposed in the second active region and having a first conductivity type; a second well region disposed in the first well region and having a second conductivity type different from the first conductivity type, wherein the first doped region is disposed in the first well region, and the second doped regions are disposed in the second well region; and a deep well region disposed in the second active region below the second well region and having the second conductivity type, wherein the second well region is configured below the first portion of the insulation pattern, the first doped region has the first conductivity type, and the second doped regions have the second conductivity type.
9. The semiconductor device of claim 1, wherein the dummy gate structure is electrically floating.
10. A method of forming a semiconductor device, comprising: forming an element isolation structure defining a first active region and a second active region in a substrate; forming a first element in the first active region of the substrate, wherein the first element comprises a gate structure formed on the substrate; forming a second element in the second active region of the substrate, wherein the second element comprises an insulation pattern embedded in the substrate and a first doped region and second doped regions formed in the substrate, the insulation pattern comprises a first portion and a second portion surrounding the first portion, the second portion and the element isolation structure define a region in the second active region where the first doped region is formed therein, and the second portion and the first portion define a region in the second active region where the second doped regions are formed therein; and forming a dummy gate structure in the second active region of the substrate, wherein the dummy gate structure comprises a first pattern formed on the first portion of the insulation pattern, a second pattern formed on the second portion of the insulation pattern, and a third pattern formed on the element isolation structure.
11. The method of claim 10, wherein the gate structure comprises a first high dielectric constant layer, a first capping layer and a first metal gate formed on the substrate sequentially, and the dummy gate structure comprises a second high dielectric constant layer, a second capping layer and a second metal gate formed on the substrate sequentially, and the first metal gate and the second metal gate are formed at the same level height respective to the substrate.
12. The method of claim 11, wherein a process of forming the first metal gate and the second metal gate comprises a chemical mechanical polishing (CMP) process.
13. The method of claim 10, wherein the second doped regions of the second element are formed to extend in a first direction and to be spaced apart from each other in a second direction.
14. The method of claim 13, wherein the first doped region of the second element is formed to surround the insulation pattern and has a conductivity type different from the second doped regions.
15. The method of claim 10, further comprising: forming a first dielectric structure between the first pattern and the second pattern of the dummy gate structure above the insulation pattern; and forming a second dielectric structure between the second pattern and the third pattern of the dummy gate structure above the insulation pattern, wherein the first dielectric structure and the second dielectric structure are spaced apart from each other.
16. The method of claim 15, wherein the first dielectric structure covers the second doped regions, and the second dielectric structure covers the first doped region.
17. The method of claim 10, wherein the substrate comprises: a first well region formed in the second active region and having a first conductivity type; a second well region formed in the first well region and having a second conductivity type different from the first conductivity type, wherein the first doped region is formed in the first well region, and the second doped regions are formed in the second well region; and a deep well region formed in the second active region below the second well region and having the second conductivity type, wherein the second well region is formed below the first portion of the insulation pattern, the first doped region has the first conductivity type, and the second doped regions have the second conductivity type.
18. The method of claim 10, wherein the dummy gate structure is electrically floating.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.
[0027]
[0028]
[0029]
[0030]
DESCRIPTION OF THE EMBODIMENTS
[0031] In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.
[0032] The invention will be described more comprehensively below with reference to the drawings for the embodiments. However, the invention may also be implemented in different forms rather than being limited by the embodiments described in the invention. Thicknesses of layer and region in the drawings are enlarged for clarity. The same reference numbers are used in the drawings and the description to indicate the same or like parts, which are not repeated in the following embodiments.
[0033] It will be understood that when an element is referred to as being on or connected to another element, it may be directly on or connected to the other element or intervening elements may be present. If an element is referred to as being directly on or directly connected to another element, there are no intervening elements present. As used herein, connection may refer to both physical and/or electrical connections, and electrical connection or coupling may refer to the presence of other elements between two elements. As used herein, electrical connection may refer to the concept including a physical connection (e.g., wired connection) and a physical disconnection (e.g., wireless connection).
[0034] As used herein, about, approximately or substantially includes the values as mentioned and the average values within the range of acceptable deviations that can be determined by those of ordinary skill in the art. Consider to the specific amount of errors related to the measurements (i.e., the limitations of the measurement system), the meaning of about may be, for example, referred to a value within one or more standard deviations of the value, or within 30%, 20%, 10%, 5%. Furthermore, the about, approximate or substantially used herein may be based on the optical property, etching property or other properties to select a more acceptable deviation range or standard deviation, but may not apply one standard deviation to all properties.
[0035] The terms used herein are used to merely describe exemplary embodiments and are not used to limit the present disclosure. In this case, unless indicated in the context specifically, otherwise the singular forms include the plural forms.
[0036]
[0037] In some embodiments, a method of forming a semiconductor device (e.g., a semiconductor device 10 shown in
[0038] Firstly, referring to
[0039] Next, a first element (e.g., a first element D1 of
[0040] Firstly, referring to
[0041] Next, referring to
[0042] Then, referring to
[0043] The high dielectric constant material layer 120 may include dielectric materials with high dielectric constants. For example, the dielectric materials with high dielectric constant may be materials having dielectric constants higher than that of silicon oxide (about 3.9). In some embodiments, the high dielectric constant material layer 120 may include HfO.sub.2, TiO.sub.2, HfZrO, Ta.sub.2O.sub.3, HfSiO.sub.4, ZrO.sub.2, ZrSiO.sub.2, LaO, AlO, ZrO, TiO, Ta.sub.2O.sub.5, Y.sub.2O.sub.3, BaZrO, HfZrO, HfLaO, HfSiO, LaSiO, AlSiO, HfTaO, HfTIO, Al.sub.2O.sub.3, Si.sub.3N.sub.4, SiON or combinations thereof. The capping material layer 130 may include TiN. The sacrificial gate material layer 140 may include polysilicon. The hard mask material layer HML may include oxides, nitrides or combinations thereof.
[0044] After that, referring to
[0045] Then, referring to
[0046] Next, a first doping process is performed on the first active region R1 and the second active region R2 to form doped regions 160a having the first conductivity type in the well region 104a at the opposite sides of the stacked structure STK and to form a doped region 160b having the first conductivity type in a region defined by the second portion 112b of the insulation pattern 112 and the element isolation structure 110 in the well region 104b. After that, a second doping process is performed on the second active region R2 to form doped regions 162 having the second conductivity type in a region defined by the second portion 112b and the first portion 112a of the insulation pattern 112 in the well region 106. As such, the second element embedded in the substrate 100 and including the insulation pattern 112, the doped region 160b, and the doped regions 162 may be formed in the second active region R2. In some embodiments, as shown in
[0047] Then, silicide layers 170 are formed in the doped regions 160a, the doped region 160b, and the doped regions 162 by a self-aligned silicide process. In some embodiments, the second element may further include the silicide layers 170 formed in the doped region 160b and the doped regions 162. The silicide layers 170 may include silicide such as tungsten silicide, titanium silicide, cobalt silicide, zirconium silicide, platinum silicide, molybdenum silicide, copper silicide, nickel silicide, or combinations thereof.
[0048] After that, referring to
[0049] Then, referring to
[0050] After that, referring to
[0051] In some embodiments, a first dielectric structure including the dielectric layers 192 and the etching stop layer 182 is formed between the sacrificial gate structures SGS on the first portion 112a and the second portion 112b of the insulation pattern 112, and a second dielectric structure including the dielectric layers 192 and the etching stop layer 182 is formed between the sacrificial gate structures SGS on the second portion 112b of the insulation pattern 112 and the element isolation structure 110. The first dielectric structure and the second dielectric structure are spaced apart from each other by the sacrificial gate structure SGS disposed on the second portion 112b of the insulation pattern 112. In some embodiments, the first dielectric structure covers the doped regions 162, and the second dielectric structure cover the doped region 160b. In some embodiments, the dielectric layer 192 may be an interlayer dielectric layer (e.g., ILD0). In some embodiments, the etching stop layer 182 may be a contact etch stop layer (CESL).
[0052] Next, referring to
[0053] Then, referring to
[0054] The dummy gate structure DGS may include first patterns P1, a second pattern P2, and a third pattern P3. The first patterns P1 are formed on the first portion 112a of the insulation pattern 112. The second pattern P2 is formed on the second portion 112b of the insulation pattern 112. The third pattern P3 is formed on the element isolation structure 110. Each of the gate structure GS and the first to third patterns P1, P2 and P3 of the dummy gate structure DGS may include the high dielectric constant layer 122, the capping layer 132, the metal gate MG, and the spacers 152. In some embodiments, the metal gate MG of the gate structure GS and the metal gate MG of the dummy gate structure DGS are formed at the same level height respective to the substrate 100. In some embodiments, the processes of forming the metal gates MG of the gate structure GS and the dummy gate structure DGS include at least two planarization processes (e.g., the CMP processes).
[0055] In some embodiments, referring to
[0056] In some embodiments, as shown in
[0057] Hereinafter, the semiconductor device 10 will be described with reference to
[0058] Referring to
[0059] In some embodiments, the gate structure GS includes a first high dielectric constant layer 122, a first capping layer 132 and a first metal gate MG disposed on the substrate 100 sequentially. The dummy gate structure DGS includes a second high dielectric constant layer 122, a second capping layer 132 and a second metal gate MG disposed on the substrate 100 sequentially. The first metal gate MG of the gate structure GS and the second metal gate MG of the dummy gate structure DGS are disposed at the same level height respective to the substrate 100.
[0060] In some embodiments, the first patterns P1 of the dummy gate structure DGS include annular patterns (as shown in
[0061] In some embodiments, the semiconductor device 10 further includes a first dielectric structure disposed between the first patterns P1 and the second pattern P2 of the dummy gate structure DGS above the insulation pattern 112 and a second dielectric structure disposed between the second pattern P2 and the third pattern P3 of the dummy gate structure DGS above the insulation pattern 112. The first dielectric structure and the second dielectric structure are spaced apart from each other. For example, the first dielectric structure and the second dielectric structure may be spaced apart from each other by the second pattern P2 of the dummy gate structure DGS. In some embodiments, the first dielectric structure covers the second doped regions 162, and the second dielectric structure covers the first doped region 160b.
[0062] In some embodiments, the substrate 100 includes a first well region (e.g., the well region 104b) disposed in the second active region R2 and having a first conductivity type, a second well region (e.g., the well region 106) disposed in the first well region and having a second conductivity type different from the conductivity type, and a deep well region (e.g., the deep well region 102b) disposed in the below the second active region R2 below the second well region and having the second conductivity type. The first doped region 160b is disposed in the first well region, and the second doped regions 162 are disposed in the second well region. In some embodiments, the second well region is configured below the first portion 112a of the insulation pattern 112, the first doped region 160b has the first conductivity type (e.g., p-type), and the second doped regions 162 have the second conductivity type (e.g., n-type). In some embodiments, the dummy gate structure DGS is electrically floating.
[0063] Based on the above, according to the semiconductor device and the method of forming the same in the aforementioned embodiments, the sacrificial gate structures in the second active region are beneficial to avoid a dishing generated in the dielectric material layer 190 formed above the second element embedded in the second active region R2 of the substrate 100 during the CMP process. As such, in the subsequence process of replacing the sacrificial gate layers with the metal gate layers, the metal materials would not retain in the dishing generated in the CMP process and thus the pollution caused by the metal materials peeling off from the dishing in the subsequent processes can be avoided. Namely, after the process of replacing the sacrificial gate layers with the metal gate layers, the sacrificial gate structures in the second active region are formed to be the dummy gate structure including the first patterns on the first portion of the insulation pattern, a second portion on the second portion of the insulation pattern, and a third pattern on the element isolation structure, and the insulation layer formed above the second element (e.g., the insulation layer including the first dielectric structure and the second dielectric structure) would not have the aforementioned dishing generated during the CMP process, and thus the undesired metal materials would not retain in the aforementioned dishing generated during the CMP process.
[0064] It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the disclosure covers modifications and variations provided that they fall within the scope of the following claims and their equivalents.