CN115985840A - Method for improving groove filling capacity and application thereof - Google Patents
Method for improving groove filling capacity and application thereof Download PDFInfo
- Publication number
- CN115985840A CN115985840A CN202211524039.4A CN202211524039A CN115985840A CN 115985840 A CN115985840 A CN 115985840A CN 202211524039 A CN202211524039 A CN 202211524039A CN 115985840 A CN115985840 A CN 115985840A
- Authority
- CN
- China
- Prior art keywords
- trench
- etching
- deposition
- film
- sio
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 69
- 238000011049 filling Methods 0.000 title claims abstract description 55
- 238000005530 etching Methods 0.000 claims abstract description 39
- 229910017855 NH 4 F Inorganic materials 0.000 claims abstract description 37
- 239000004065 semiconductor Substances 0.000 claims abstract description 25
- DDFHBQSCUXNBSA-UHFFFAOYSA-N 5-(5-carboxythiophen-2-yl)thiophene-2-carboxylic acid Chemical compound S1C(C(=O)O)=CC=C1C1=CC=C(C(O)=O)S1 DDFHBQSCUXNBSA-UHFFFAOYSA-N 0.000 claims abstract description 17
- 238000005137 deposition process Methods 0.000 claims abstract description 13
- 238000000151 deposition Methods 0.000 claims description 38
- 238000006243 chemical reaction Methods 0.000 claims description 22
- 239000007787 solid Substances 0.000 claims description 18
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 claims description 11
- 229910052731 fluorine Inorganic materials 0.000 claims description 11
- 239000011737 fluorine Substances 0.000 claims description 11
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 claims description 10
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 claims description 10
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 239000000758 substrate Substances 0.000 claims description 6
- -1 fluoride ions Chemical class 0.000 claims description 3
- 239000010408 film Substances 0.000 abstract description 46
- 230000008021 deposition Effects 0.000 abstract description 23
- 230000000694 effects Effects 0.000 abstract description 8
- 238000003486 chemical etching Methods 0.000 abstract description 6
- 239000010409 thin film Substances 0.000 abstract description 4
- 239000007789 gas Substances 0.000 description 33
- 229910004298 SiO 2 Inorganic materials 0.000 description 21
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 19
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 7
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 5
- 238000005229 chemical vapour deposition Methods 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 239000012265 solid product Substances 0.000 description 5
- 239000006227 byproduct Substances 0.000 description 4
- 238000002955 isolation Methods 0.000 description 4
- 238000000859 sublimation Methods 0.000 description 4
- 230000008022 sublimation Effects 0.000 description 4
- 239000000112 cooling gas Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- QKCGXXHCELUCKW-UHFFFAOYSA-N n-[4-[4-(dinaphthalen-2-ylamino)phenyl]phenyl]-n-naphthalen-2-ylnaphthalen-2-amine Chemical compound C1=CC=CC2=CC(N(C=3C=CC(=CC=3)C=3C=CC(=CC=3)N(C=3C=C4C=CC=CC4=CC=3)C=3C=C4C=CC=CC4=CC=3)C3=CC4=CC=CC=C4C=C3)=CC=C21 QKCGXXHCELUCKW-UHFFFAOYSA-N 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- 238000005979 thermal decomposition reaction Methods 0.000 description 2
- MKYBYDHXWVHEJW-UHFFFAOYSA-N N-[1-oxo-1-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propan-2-yl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(C(C)NC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 MKYBYDHXWVHEJW-UHFFFAOYSA-N 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- LDDQLRUQCUTJBB-UHFFFAOYSA-N ammonium fluoride Chemical compound [NH4+].[F-] LDDQLRUQCUTJBB-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- LDDQLRUQCUTJBB-UHFFFAOYSA-O azanium;hydrofluoride Chemical compound [NH4+].F LDDQLRUQCUTJBB-UHFFFAOYSA-O 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 238000005429 filling process Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 229910000077 silane Inorganic materials 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Landscapes
- Element Separation (AREA)
- Formation Of Insulating Films (AREA)
Abstract
The invention provides a method for improving groove filling capacity and application thereof, relating to the technical field of semiconductors and comprising the following steps: ammonium fluoride and deposited SiO are used in filling trenches by deposition-etch-deposition 2 The thin film reacts to carry out etching, and the entrance of the groove is opened, thereby solving the problem of NF in the traditional method 3 The reduction of the depth-to-width ratio of the trench is not obvious during the deposition process caused by the isotropy of the chemical etching and the deposited film at the bottom of the trench is NF again 3 The technical problem of low deposition efficiency caused by etching off is achieved, and NH is prevented 4 F and/or NH 4 F.HF for SiO deposited at trench bottom 2 The technical effect of further etching the film is finally realizedThe technical effect of completely filling the groove is achieved by the cycle of the over-deposition and the etching.
Description
Technical Field
The invention relates to the technical field of semiconductors, in particular to a method for improving groove filling capacity and application thereof.
Background
The integration level of semiconductor devices is continuously improved and the process characteristic size is continuously reduced, so that the width of gaps or grooves of filling materials is smaller and smaller, the filling depth-to-width ratio is increased, and the difficulty of filling the grooves is increased. When the groove is deposited to realize filling, deposition accumulation is easily generated on the shoulder part of the side wall of the groove, and when the deposition accumulation reaches a certain degree, the opening of the groove is closed, so that a hole is formed in the groove, the problems of device bridging and the like are caused, and the performance and the reliability of the device are seriously influenced.
The advent of High Density Plasma (HDP) Chemical Vapor Deposition (CVD) process (HDP-CVD) has solved to a great extent the above-mentioned problems, and because it can etch while depositing, it can reform the partially filled trench with an etching step, remove the excess deposit accumulated on the sidewall of the trench, and specifically, fill the trench by a deposition-etch-redeposit-re-etch cycle, and fill the gap with high aspect ratio, therefore, HDP-CVD process is widely used in the manufacture of semiconductor integrated circuits.
Currently, HDP-CVD processes are typically performed with SiH4 (silane) + O 2 Filling the trench with (oxygen) deposited silicon oxide, and then NF 3 And (nitrogen trifluoride) etching the partially filled groove to open, then depositing silicon dioxide to fill the groove, and performing multiple cycles on the steps according to the structure of the groove to realize complete filling. However, when filling trenches with high aspect ratios, due to NF 3 When etching, the film filled in the groove is isotropically etched, so that the deposition efficiency is low, and the depth-to-width ratio cannot be reduced to the maximum extent; at the same time, NF 3 After dissociation, the isotropic chemical etching for filling the groove can cause the film deposited at the bottom to be etched again to a certain degree, so that the deposition efficiency is low; thus, NF 3 The isotropy of the chemical etching causes the depth-to-width ratio of the trench to be reduced insignificantly during the deposition process, and the filling difficulty of the trench with high depth-to-width ratio cannot be reduced obviously.
In view of the above, the present invention is particularly proposed.
Disclosure of Invention
One objective of the present invention is to provide a method for improving trench filling capability, which can improve the filling capability of a trench with a high aspect ratio and can improve the filling efficiency of a trench with the same aspect ratio.
It is a further object of the present invention to provide a semiconductor device that can fill a trench using the above method.
The invention also aims to provide application of the method for improving the groove filling capacity, which can improve the performance and the reliability of the semiconductor device.
In order to achieve the above purpose of the present invention, the following technical solutions are adopted:
in a first aspect, a method for improving trench filling capability includes the following steps:
(1) The deposition process comprises the following steps: providing a substrate having a trench, depositing SiO in the trench 2 A film;
(2) An etching process: ammonium fluoride gas and SiO deposited in step (1) 2 Reacting the film, and etching to open the inlet of the groove;
(3) And (3) circulating the step (1) and the step (2) until the groove filling is completed.
Further, the step (2) comprises the following steps:
ammonium fluoride gas and SiO deposited in step (1) 2 Reacting the film at a first temperature to obtain fluorine-containing ammonium silicate solid;
and (3) decomposing the fluorine-containing ammonium silicate solid into gas under the heating at a second temperature, and completing etching to open the groove inlet.
Further, the first temperature is below 50 ℃.
Further, the second temperature is above 100 ℃.
In the present invention, when filling the trench by deposition-etch-deposition, the etchant ammonium fluoride gas and deposited SiO are used 2 The film reacts to generate fluorine-containing ammonium silicate solid, and then the fluorine-containing ammonium silicate solid is heated and decomposed into gas to complete etching so as to open the inlet of the groove.
Wherein the manner of deposition-etch-deposition includes, but is not limited to, utilizing HDP-CVD process.
Further, the ammonium fluoride gas is composed of fluoride ions and NH - Or NH 2 - Or NH 3 - And (3) the reaction is completed.
Further, the ammonium fluoride gas includes NH 4 F gas and NH 4 At least one of F.HF gas.
Further, NH in the present invention 4 F and/or NH 4 F.HF is composed of NF 3 And NH 3 Formed by reaction, may be NF 3 And NH 3 Generated by reaction in a remote plasma generator of the HDP apparatus.
Further, the fluorine-containing ammonium silicate in the present invention includes (NH) 4 ) 2 SiF 6 。
Further, the number of times of circulating the step (1) and the step (2) is 1-10 times.
In a second aspect, a semiconductor device for filling a trench using a method as claimed in any one of the preceding claims, the semiconductor device comprising a remote plasma generator means.
Further, the semiconductor apparatus includes an HDP-CVD apparatus.
In a third aspect, use of a method as claimed in any preceding claim in the manufacture of a semiconductor integrated circuit.
Further, the semiconductor integrated circuit manufacturing comprises a shallow trench isolation filling process.
Compared with the prior art, the invention has at least the following beneficial effects:
the method for improving the filling capacity of the groove provided by the invention is realized by NH in the deposition-etching-deposition process of HDP-CVD 4 F and/or NH 4 F.HF (Etchant ) with deposited SiO 2 The film is reacted to Etch (Etch), and the reacted solid product (NH) 4 ) 2 SiF 6 Decomposed into gas, and etched to form V-shaped cross section, thereby improving the subsequent filling effect, and improving the filling capability of HDP-CVD process for high aspect ratio holes, more importantly, due to (NH) 4 ) 2 SiF 6 Is a solid product, thus protecting SiO which does not need to be etched 2 Film portion, blocking NH 4 F and/or NH 4 F.HF for SiO deposited at trench bottom 2 Further etching of the film, thereby avoiding NF in the conventional method 3 The isotropy of the chemical etching causes insignificant reduction of the aspect ratio of the trench and the bottom of the trench during depositionThe deposited film is etched again, which results in the technical problem of low deposition efficiency.
The semiconductor device provided by the invention comprises a remote plasma generator device, and the filling of the groove can be realized by utilizing the method.
The application of the method for improving the groove filling capability can improve the performance and the reliability of the semiconductor device.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a process flow operational diagram of deposition-etch-deposition in an HDP-CVD process according to one embodiment of the present invention;
fig. 2 is a schematic diagram of a deposition-etch-deposition process according to an embodiment of the present invention.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
According to a first aspect of the present invention, there is provided a method of improving trench filling capability, comprising the steps of:
(1) The deposition process comprises the following steps: providing a substrate having a trench, depositing SiO in the trench 2 A film;
(2) An etching process: ammonium fluoride gas and SiO deposited in step (1) 2 Reacting the film, and etching to open the inlet of the groove;
(3) And (3) circulating the step (1) and the step (2) until the groove filling is completed.
In the invention, deposition refers to film deposition, refers to any process of physically depositing a film on a silicon wafer substrate, belongs to a process in film manufacturing, and can grow various conductive thin film layers, insulating thin film layers and the like on the silicon wafer through the film deposition process; etching refers to etching away the film with an Etchant (Etchant).
The method for improving the groove filling capacity, the ammonium fluoride gas and the deposited SiO 2 The film reacts to carry out etching (Etch), and the reacted solid product can be heated and decomposed into gas, so that the etching is completed to open the inlet of the groove to form a cross section similar to a V shape, the subsequent filling effect is favorably improved, and the filling capacity of the process for the groove with the high depth-to-width ratio is improved.
In a preferred embodiment, the deposition process of step (1) of the present invention is carried out by SiH4 and O 2 Reaction to form SiO 2 To be realized.
In a preferred embodiment, the deposition process of the present invention is carried out at a temperature of 300-800 deg.C, such as, but not limited to, 300 deg.C, 400 deg.C, 500 deg.C, 600 deg.C, 700 deg.C, 800 deg.C, which is more advantageous for increasing the deposition rate of SiO 2 The effect of (1).
In a preferred embodiment, step (2) of the present invention comprises the following steps:
ammonium fluoride gas and SiO deposited in step (1) 2 Reacting the film at a first temperature to obtain fluorine-containing ammonium silicate solid;
and (3) decomposing the fluorine-containing ammonium silicate solid into gas under the heating at a second temperature, and completing etching to open the groove inlet.
In the present invention, the first temperature may be below 50 ℃, but is not limited thereto, and it is more advantageous to increase the concentration of the ammonium fluoride gas and SiO 2 The reaction effect of the film; the second temperature may be above 100 ℃, but is not limited thereto, and is more advantageous for improving the thermal decomposition effect of the fluorine-containing ammonium silicate solid.
In a preferred embodiment, the ammonium fluoride gas of the present invention is formed by reacting fluoride ions with fluorine ionsNH - Or NH 2 - Or NH 3 - The reaction is completed.
Ammonium fluoride gases of the present invention include, but are not limited to, NH 4 F gas and NH 4 At least one of F.HF gas.
In the present invention, NH 4 The Chinese name of F is ammonium fluoride, CAS number 12125-01-8; NH (NH) 4 The Chinese name of F.HF is ammonium hydrogen fluoride (NH) 4 HF 2 ) CAS number 1341-49-7; siO 2 2 Is known as silica.
In a preferred embodiment, NH in the present invention 4 F and/or NH 4 F.HF may be NF 3 And NH 3 Formed by reaction of formula NF 3 +NH 3 →NH 4 F+NH 4 F·HF。
In a preferred embodiment, NH 4 F and/or NH 4 F.HF may be NF 3 And NH 3 The reaction is generated in a remote plasma (remote plasma) generator of the HDP equipment, and NF is carried out by utilizing the remote plasma generator of the HDP equipment 3 And NH 3 To form NH 4 F and/or NH 4 F, HF, the operability of the process is improved, and NF can be reduced 3 And NH 3 The reaction temperature of (1).
In the present invention, NH 4 F and/or NH 4 F.HF and deposited SiO 2 When the film is reacted, the temperature can be cooled to below 50 ℃ by using furnace side cooling gas of HDP equipment, and the chemical reaction formula is NH 4 F or NH 4 F·HF+SiO 2 →(NH 4 ) 2 SiF 6 (solid) + H 2 O, siO at the inlet of the groove 2 The film is etched away to open the trench entrance.
In the present invention, (NH) 4 ) 2 SiF 6 Is decomposed into HN by heating 3 HF and SiF 4 In this case, the plasma heating temperature of the HDP apparatus may be set to 100 ℃ or higher, (NH) 4 ) 2 SiF 6 The chemical reaction formula of the thermal decomposition is (NH) 4 ) 2 SiF 6 (solid) → SiF 4 (gas) + NH 3 (gas) + HF (gas).
The method for improving the groove filling capacity can deposit SiO in a deposition-etching-deposition mode in an HDP-CVD (high-density plasma chemical vapor deposition) process 2 When the film is used to fill the trench, NH is used 4 F and/or NH 4 F.HF and deposited SiO 2 Film reaction to form solid (NH) 4 ) 2 SiF 6 After (NH) 4 ) 2 SiF 6 And the silicon nitride is heated and decomposed into gas, etching is completed to open the inlet of the groove, and deposition, etching and deposition are recycled until the whole groove is filled.
In the present invention, the HDP-CVD process refers to a high-density plasma (HDP) Chemical Vapor Deposition (CVD) process (HPDCVD), which is one of the common processes in semiconductor integrated circuit manufacturing, has the characteristic of deposition and etching, and is generally used for filling a gap with a high aspect ratio, for example, a silicon dioxide layer formed by the HDP-CVD process can be used for filling a gap of an inter-metal dielectric layer (PMD), a pre-metal dielectric layer (MD), and a Shallow Trench Isolation (STI).
In the present invention, the number of cycles of dep-etch-dep may be adjusted according to the trench structure to achieve complete filling of the trench, for example, the number of cycles of dep-etch-dep may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, but is not limited thereto.
An exemplary method for improving trench filling capability, process flow and schematic diagram are shown in fig. 1 and 2, comprising the steps of:
(1)SiO 2 film Deposition (Deposition: dep SiO) 2 )：
Providing a substrate with a trench, depositing SiO in the trench by HDP-CVD process 2 Film of the formula SiH4+ O 2 →SiO 2 Wherein, siO 2 The temperature of the film deposition is between 300 and 800 ℃;
(2) Etchant Generation (etch Generation):
the etchant is generated by using a remote plasma on the HDP equipment, and the chemical reaction formula is NF 3 +NH 3 →NH 4 F+NH 4 F·HF，NH 4 F and/or NH 4 F and HF are etchants (Etchant);
(3) Etching Process (Etch Process):
utilizing the etchant NH of the step (2) 4 F and/or NH 4 F, HF to SiO 2 Etching the film (Etch) with a chemical reaction formula of NH 4 F or NH 4 F·HF+SiO 2 →(NH 4 ) 2 SiF 6 (solid) + H 2 O, the reaction temperature of which is below 50 ℃, and the temperature of which can be cooled to below 50 ℃ by using the furnace side cooling gas of HDP equipment;
sublimation (Sublimation), i.e. removal of by-products (NH) 4 ) 2 SiF 6 (Remove the by-products):
(NH 4 ) 2 SiF 6 (solid) decomposes at a temperature of 100 ℃ or higher to a gas having a chemical reaction formula of (NH) 4 ) 2 SiF 6 (solid) → SiF 4 (gas) + NH 3 (gas ) + HF (gas ), plasma heating temperature can be used to above 100 ℃;
thereby, siO at the inlet of the trench 2 Etching the film to open the entrance of the trench, and completing the first etching;
(4) After the first etching in the step (3) is finished, returning to the step (1) to continue depositing SiO 2 Film, namely completing primary deposition-etching-deposition;
depending on the trench structure, the above steps are cycled as many times as necessary (recycled x cycles per needed), preferably 1 to 10 times, to complete the SiO 2 Film to full trench fill (Dep SiO) 2 cap to complete the whole gapfill process)。
The method for improving the groove filling capacity provided by the invention can control the reaction temperature of each step through the existing hardware configuration of the HDP equipment so as to realize the improvement of the subsequent groove filling section, namely, a section similar to a V shape is formed, and the filling capacity of the HDP-CVD process to the groove with the high depth-to-width ratio is improved.
The method for improving the groove filling capacity provided by the invention is realized by NH in a deposition-etching-deposition process of HDP-CVD 4 F and/or NH 4 F.HF (Etchant ) and deposited SiO 2 The film is reacted to Etch (Etch), and the reacted solid product (NH) 4 ) 2 SiF 6 Decomposed into gas, and etched to form V-shaped cross section, thereby improving the subsequent filling effect, and improving the filling capability of HDP-CVD process for high aspect ratio holes, more importantly, due to (NH) 4 ) 2 SiF 6 Is a solid product, thus protecting SiO which does not need to be etched 2 Film portion, blocking NH 4 F and/or NH 4 F.HF for SiO deposited at trench bottom 2 Further etching of the thin film, thereby avoiding NF in the conventional method 3 The isotropy of the chemical etching causes the problem that the depth-to-width ratio of the trench is not reduced significantly during the deposition process and the deposition efficiency is low because the deposited film at the bottom of the trench is etched again.
According to a second aspect of the present invention there is provided a semiconductor device filled with a trench using a method as defined in any one of the preceding claims.
The semiconductor device provided by the invention comprises a remote plasma generator device, and the filling of the groove can be realized by utilizing the method.
In a preferred embodiment, the semiconductor apparatus of the present invention includes, but is not limited to, an HDP-CVD apparatus.
According to a third aspect of the present invention, there is provided a use of any one of the above methods for improving trench filling capability in semiconductor integrated circuit manufacturing.
In a preferred embodiment, semiconductor integrated circuit fabrication includes a shallow trench isolation fill process.
The method for improving the groove filling capacity is applicable to a Shallow Trench Isolation (STI) process, can improve the filling capacity of the groove with the high aspect ratio and the filling efficiency of the groove with the same aspect ratio, and can improve the performance and the reliability of a semiconductor device.
The invention is further illustrated by the following examples. The materials in the examples are prepared according to known methods or are directly commercially available, unless otherwise specified.
Example 1
A method for improving trench filling capability, the process flow is shown in fig. 1 and fig. 2, and includes the following steps:
(1)SiO 2 film Deposition (Deposition: dep SiO) 2 )：
Providing a substrate with a trench, depositing SiO in the trench by HDP-CVD process 2 Film of the chemical formula SiH4+ O 2 →SiO 2 Wherein, siO 2 The temperature of film deposition is 500 ℃;
(2) Etchant Generation (etch Generation):
the etchant is generated by using a remote plasma on the HDP equipment, and the chemical reaction formula is NF 3 +NH 3 →NH 4 F+NH 4 F·HF，NH 4 F and/or NH 4 F and HF are etchants (Etchant);
(3) Etching Process (Etch Process):
utilizing the etchant NH of the step (2) 4 F and/or NH 4 F, HF to SiO 2 Etching the film (Etch) with a chemical reaction formula of NH 4 F or NH 4 F·HF+SiO 2 →(NH 4 ) 2 SiF 6 (solid) + H 2 O, the reaction temperature is 40 ℃, and the temperature is cooled to 40 ℃ by using furnace edge cooling gas;
sublimation (Sublimation), i.e. removal of by-products (NH) 4 ) 2 SiF 6 (Remove the by-products):
(NH 4 ) 2 SiF 6 (solid) decomposes at a temperature of 120 ℃ to a gas having the chemical reaction formula (NH) 4 ) 2 SiF 6 (solid) → SiF 4 (gas) + NH 3 (gas) + HF (gas), useHeating the plasma to 120 ℃;
thereby, siO at the inlet of the groove 2 Etching the film to open the entrance of the trench, and completing the first etching;
(4) After the first etching in the step (3) is finished, returning to the step (1) to continue depositing SiO 2 Film, namely completing primary deposition, etching and deposition;
the steps are circulated until SiO is finished 2 And filling the whole groove with the film.
Comparative example 1
This comparative example differs from example 1 in that it uses NF 3 (Nitrogen trifluoride) etching the filled trench to open, and then depositing SiO 2 The film fills the trench.
However, for high aspect ratio trench fill, due to NF 3 The SiO filled in the groove can be etched 2 The film causes isotropic etching and therefore does not minimize the aspect ratio, and also causes the deposited film at the bottom of the trench to be etched away again to some extent, resulting in low deposition efficiency.
Thus, NH equivalent to that of example 1 4 F and/or NH 4 NF in the conventional HDP-CVD process compared with F.HF 3 The isotropy of the chemical etching causes the depth-to-width ratio of the trench to be reduced insignificantly during the deposition process, the filling difficulty of the trench with high depth-to-width ratio cannot be reduced obviously, and the deposition efficiency is low.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (10)
1. A method for improving trench filling capability, comprising the steps of:
(1) The deposition process comprises the following steps: providing a substrate having a trench, depositing SiO in the trench 2 A film;
(2) An etching process comprises the following steps: ammonium fluoride gas and SiO deposited in step (1) 2 Reacting the film, and etching to open the inlet of the groove;
(3) And (3) circulating the step (1) and the step (2) until the groove filling is completed.
2. The method of claim 1, wherein step (2) comprises:
ammonium fluoride gas and SiO deposited in step (1) 2 Reacting the film at a first temperature to obtain fluorine-containing ammonium silicate solid;
the fluorine-containing ammonium silicate solid is heated at a second temperature to decompose into a gas, completing the etching to open the trench inlet.
3. The method of claim 2, wherein the first temperature is below 50 ℃.
4. The method of claim 2, wherein the second temperature is above 100 ℃.
5. The method of any of claims 1-4, wherein the ammonium fluoride gas is formed from fluoride ions and NH - Or NH 2 -, or NH 3 - The reaction is completed.
6. The method of claim 5, wherein the ammonium fluoride gas comprises NH 4 F gas and NH 4 At least one of F.HF gas.
7. The method of claim 1, wherein the number of times steps (1) and (2) are cycled is 1-10 times.
8. A semiconductor device for filling a trench by a method according to any of claims 1 to 7, characterized in that the semiconductor device comprises a remote plasma generator means.
9. The semiconductor apparatus of claim 8, wherein the semiconductor apparatus comprises an HDP-CVD apparatus.
10. Use of a method according to any of claims 1-7 in the manufacture of semiconductor integrated circuits.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211524039.4A CN115985840A (en) | 2022-11-30 | 2022-11-30 | Method for improving groove filling capacity and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211524039.4A CN115985840A (en) | 2022-11-30 | 2022-11-30 | Method for improving groove filling capacity and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115985840A true CN115985840A (en) | 2023-04-18 |
Family
ID=85971244
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211524039.4A Pending CN115985840A (en) | 2022-11-30 | 2022-11-30 | Method for improving groove filling capacity and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115985840A (en) |
-
2022
- 2022-11-30 CN CN202211524039.4A patent/CN115985840A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101548381B1 (en) | Protective layer to enable damage free gap fill | |
| KR100878015B1 (en) | Method for removing of oxides and method for filling a trench using the same | |
| US7033945B2 (en) | Gap filling with a composite layer | |
| US6743727B2 (en) | Method of etching high aspect ratio openings | |
| KR100689826B1 (en) | High density plasma chemical vapor deposition methods using a fluorine-based chemical etching gas and methods of fabricating a semiconductor device employing the same | |
| US6794290B1 (en) | Method of chemical modification of structure topography | |
| US6335261B1 (en) | Directional CVD process with optimized etchback | |
| US7763522B2 (en) | Method of high density plasma gap-filling with minimization of gas phase nucleation | |
| EP0540321B1 (en) | A method for fabricating an interlayer-dielectric film of BPSG in a semiconductor device | |
| JPH06314777A (en) | Manufacture of semiconductor device | |
| US6077786A (en) | Methods and apparatus for filling high aspect ratio structures with silicate glass | |
| KR100470973B1 (en) | High density plasma chemical vapor deposition process | |
| US7235856B1 (en) | Trench isolation for semiconductor devices | |
| US6645873B2 (en) | Method for manufacturing a semiconductor device | |
| CN101473426A (en) | Dielectric deposition and etch back processes for bottom up gapfill | |
| US6589854B2 (en) | Method of forming shallow trench isolation | |
| US20010012701A1 (en) | Method of forming a silicon nitride thin film | |
| US6548426B1 (en) | Method for improving a quality of dielectric layer and semiconductor device | |
| CN115985840A (en) | Method for improving groove filling capacity and application thereof | |
| KR100772275B1 (en) | Semiconductor device and manufacturing method thereof | |
| JPH0878408A (en) | Manufacture of semiconductor device | |
| JPH10294290A (en) | Manufacture of semiconductor device | |
| TW202111862A (en) | Method for fabricating dielectric layer and applictions thereof | |
| CN118173495A (en) | Filling method of semiconductor groove and semiconductor groove structure | |
| CN115332068A (en) | Method for manufacturing semiconductor device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |