WO1996027032A1 - Chemical vapor deposition utilizing a precursor - Google Patents
Chemical vapor deposition utilizing a precursor Download PDFInfo
- Publication number
- WO1996027032A1 WO1996027032A1 PCT/US1996/001773 US9601773W WO9627032A1 WO 1996027032 A1 WO1996027032 A1 WO 1996027032A1 US 9601773 W US9601773 W US 9601773W WO 9627032 A1 WO9627032 A1 WO 9627032A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- liquid
- solution
- precursor
- chamber
- specified
- Prior art date
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
- C23C16/448—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials
- C23C16/4485—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials by evaporation without using carrier gas in contact with the source material
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
- C23C16/448—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials
- C23C16/4486—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials by producing an aerosol and subsequent evaporation of the droplets or particles
Definitions
- the invention relates to the manufacture of semiconductor circuits on semiconductor wafers, and more particularly to chemical vapor depositions of materials on the wafer.
- a large number of nonvolatile metal organic precursors which are suitable in microelectronics applications for chemical vapor deposition (CVD) of thin films are solids at temperatures at or below 1500 Kelvin and at pressures at or above 10 "10 Torr.
- a majority of metal-organic compounds with attributes desirable for CVD are solids. These compounds have chemical stability, molecular structures, and reactivity which make them ideally suited for CVD application.
- vapor transport is difficult to perform under temperatures and pressures typically utilized in semiconductor manufacture. Thus, vapor transport of these precursors is a major hinderance to the implementation of the precursors in a production environment.
- the precursor has a sufficient vapor pressure, then sublimation of the precursor for transportation of its vapor is the only option available, however this is difficult to control in a manufacturing environment. Solid precursors have been dissolved, transported, and delivered in organic solution, but these solutions usually leave a large carbon residue.
- CVD chemical vapor deposition
- the invention features dissolving a volitile or nonvolatile precursor, either solid or liquid, in a solution and delivering the precursor in the solution to a CVD chamber.
- the invention is a very efficient method for transporting a nonvolatile precursor for CVD in the manufacturing environment and incorporates a minimum amount of unwanted by-product in the desired film.
- the method entails a process which is easily controlled and therefore predictable with repeatable results.
- the invention is a method directed to the use of a nonvolatile precursor, either solid or liquid, in a chemical vapor deposition (CVD) process.
- a solid precursor as referenced herein, is a precursor which is in a solid state at a temperature at or below 1500 Kelvin and at a pressure at or above 10 l ⁇ Torr
- a liquid precursor as referenced herein, is a precursor which is in a liquid state at a temperature at or below 1500 Kelvin and at a pressure at or above 10 "10 Torr.
- the nonvolatile precursor is dissolved in a solvent to form a solution.
- the nonvolatile precursor is then transported in the solution at a pressure and a temperature necessary to maintain it as a liquid to the CVD chamber.
- the solution is transported in a continuous liquid stream to the CVD chamber.
- a continuous liquid stream is an unbroken non-nebulized stream of liquid which may be passed to the chamber without interruption or may be passed to the chamber in a pulse or batch. The pulse or batch can be thought of as a portion of the solution.
- the solution becomes a gas during rapid evaporation of the solution at a high temperature and at a low pressure.
- the gaseous form of the precursor reacts with a reactant at the heated surface of the wafer.
- the method of the invention can be used in liquid source chemical vapor deposition where the solution is applied to the wafer before being evaporated.
- Brief Description of the Drawing Figure 1 is a cross section of a simplified representation of the equipment used to perform a chemical vapor deposition on a semiconductor wafer.
- the invention is a method directed to the use of a nonvolatile precursor suitable for chemical vapor deposition (CVD).
- the nonvolatile precursor may be a solid or a liquid.
- the solid precursor as referenced herein, is a precursor which is in a solid state at a temperature at or below 1500 Kelvin and at a pressure at or above 10 " '° Torr.
- the liquid precursor as referenced herein, is in a liquid state at a temperature at or below 1500 degrees Kelvin and at a pressure at or above 10 "10 Torr.
- the method can be understood by studying Figure 1 in conjunction with the following description. Using the method of the invention, the nonvolatile precursor is dissolved in a solvent to form a solution 1 of the precursor and the solvent.
- the solvent can be either a reactive component which makes up a part of the film or it can be simply a nonreactive inert carrier.
- the solution 1 is formed in a chamber 2.
- the solution 1 is then transported in liquid form at elevated pressures and/or reduced temperatures to a chamber 3 through a transport device 4.
- the liquid is transported as a continuous liquid stream to the chamber 3.
- a continuous liquid stream is an unbroken non-nebulized stream of liquid which may be passed to the chamber without interruption or may be passed to the chamber in a pulse or batch.
- the pulse or batch can be thought of as a portion of the solution.
- the solution 1 becomes a gas upon entry to the chamber 3.
- the chamber 3 is held at a high enough temperature and a low enough pressure to effect rapid evaporation of the solution 1.
- the precursor remains in the gas phase until it reacts with a reactant at a heated surface of the wafer 5.
- the reactant may be either the solvent in its gaseous state or may be another gas injected into the chamber 3. In either case a material is produced during the reaction and deposited as a film on the wafer 5. Typically, a gaseous by-product is also produced in the reaction.
- One example of the first embodiment comprises a solid precursor of bis(cyclopentadienly)titanium diazide (Tiaz) dissolved in liquid ammonia (LNH 3 ) to form a solution 1 of Tiaz in LNH 3 in chamber 2 when the temperature of chamber 2 is 20° C or less and the pressure is 120 psi or greater.
- the Tiaz in LNH 3 is then transported to the chamber 3 through the transport device 4.
- the temperature and pressure of the transport device 4 are regulated in order to keep the solution in it liquid form. In this example the temperature is 20° or less and the pressure is 120 psi or greater.
- the solution 1 immediately vaporizes upon entry into chamber 3.
- the rapid evaporation occurs because the chamber 3 is held at a temperature of 100° C and a pressure of 500 millitorr and the water surface is held at 550° C. Hydrogen is injected into the chamber and combines with the vaporized Tiaz to form titanium nitride which is deposited on the wafer as a thin film. A by-product cyclopentadiene remains and is pumped from the chamber with the ammonia vapor.
- the temperatures and pressures may be varied as long as the temperature and pressure of the chamber and transport device allow the precursor to remain dissolved in the solution.
- the temperature and pressure of the chamber may vary as long as the solution is vaporized.
- the solution 1 is applied to the wafer 5 before being evaporated.
- This is typically referred to as liquid source chemical vapor deposition.
- the solution is delivered through a nebulizer which delivers a very fine mist that settles evenly over the entire wafer.
- the temperature of the wafer 5 may be either higher, or lower, or the same as the temperature of the solution 1.
- the wafer temperature and chamber 3 pressure must be maintained so that the solvent evaporates upon contact with the wafer surface and so that the precursor reacts immediately with the reactant gas, which is either injected into the chamber or formed during evaporation of the solution. to deposit a film.
- the solution remains on the wafer until the wafer temperature is increased to evaporate the solvent.
- the gaseous state of the precursor reacts with a gas reactant thereby producing a material deposited as a film on the wafer surface.
- the reaction typically produces a gaseous by-product in addition to the deposited film.
- the by-product and the solvent vapor in the case where the vapor doesn't react with the precursor to form the film, are then removed from the chamber 3.
- An example of the process of the second embodiment comprises a precursor, zirconium tetrachloride, dissolved in a solvent, silicon tetrachloride, to form a solution in chamber 2 when the temperature of the chamber 2 is between 60° and 10° C and the pressure is 60 psi or greater.
- the solution is then transported to the chamber 3 through the transport device 4.
- the temperature and pressure of the transport device 4 are regulated in order to maintain the solution in its liquid form.
- the temperature and pressure of the transport device 4 are the same as the temperature and pressure of chamber 2.
- Chamber 3 is held at a pressure of 10 torr in order to help facilitate the vaporization of the solution on the wafer.
- the wafer temperature is 600° C.
- the zirconium tetrachloride in silicon tetrachloride solution is injected into the chamber 3 and reacts at the wafer surface to form a vapor and combines with hydrogen to form zirconium suicide which is deposited on the wafer to form a thin film.
- a by-product, hydrogen chloride, is formed and is pumped from the chamber with the excess silicon tetrachloride.
- Ideal solvents for this application are inorganic liquids such as: liquid ammonia (NH 3 ), liquid NO 2 , liquid SO 2 , liquid TiCl 4 , liquid TaCl 5 , liquid WF 6 , liquid SiCl 4 , borazine, dimethyl hydrazine, liquid xenonflourides, liquid phosphine, liquid arsine, diethylzinc, BC1 3 , BF 3 , SF 6 , H 2 S, SiF 4 , CBrF 3 , CC1 2 F 2 , CC1 3 F, CC1F 3 , CC1 4 , SiH 2 Cl 2 .
- halogens in addition to halogens, interhalogens, and pseudohalogens may be used as the solvent in this application.
- solvents are gases at room temperature but are easily maintained as liquids with elevated pressure and reduced temperature. For example, ammonia boils at -33° C and is an excellent solvent. It is a further advantage that these gases are easily available at a low cost at the present time.
- the following gases may be selected as reactant gases for forming the deposited film: hydrogen, ammonia, or silane.
- nonvolatile liquid precursors suitable for forming films on semiconductor wafers by the method of the invention: bizcylcopentadyenyltitaniumdyazide, indenyltris(dimethylamido)zirconium, cyclopentadienyltris(diethylamido)titanium, and bis(cyclopentadienyl)bis(dimethylamido)titanium.
- the invention provides an efficient method for transporting nonvolatile precursors for CVD in the manufacturing environment.
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- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Dispersion Chemistry (AREA)
- Chemical Vapour Deposition (AREA)
- Electrodes Of Semiconductors (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1019970705999A KR100326744B1 (en) | 1995-02-28 | 1996-02-09 | Chemical Vapor Deposition Utilizing a Precursor |
JP52626896A JP3787574B2 (en) | 1995-02-28 | 1996-02-09 | Chemical vapor deposition using a precursor |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US39594295A | 1995-02-28 | 1995-02-28 | |
US08/395,942 | 1995-02-28 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996027032A1 true WO1996027032A1 (en) | 1996-09-06 |
Family
ID=23565187
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1996/001773 WO1996027032A1 (en) | 1995-02-28 | 1996-02-09 | Chemical vapor deposition utilizing a precursor |
Country Status (3)
Country | Link |
---|---|
JP (1) | JP3787574B2 (en) |
KR (1) | KR100326744B1 (en) |
WO (1) | WO1996027032A1 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8399056B2 (en) | 2006-06-02 | 2013-03-19 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Method of forming high-k dielectric films based on novel titanium, zirconium, and hafnium precursors and their use for semiconductor manufacturing |
US9045509B2 (en) | 2009-08-14 | 2015-06-02 | American Air Liquide, Inc. | Hafnium- and zirconium-containing precursors and methods of using the same |
US9499571B2 (en) | 2014-12-23 | 2016-11-22 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Germanium- and zirconium-containing compositions for vapor deposition of zirconium-containing films |
US9663547B2 (en) | 2014-12-23 | 2017-05-30 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Silicon- and Zirconium-containing compositions for vapor deposition of Zirconium-containing films |
US10106568B2 (en) | 2016-10-28 | 2018-10-23 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Hafnium-containing film forming compositions for vapor deposition of hafnium-containing films |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1986006361A1 (en) * | 1985-04-26 | 1986-11-06 | Sri International | Preparing metal compounds, alloys and metals by pyrolysis |
US4970093A (en) * | 1990-04-12 | 1990-11-13 | University Of Colorado Foundation | Chemical deposition methods using supercritical fluid solutions |
US5300321A (en) * | 1992-05-12 | 1994-04-05 | Kawasaki Steel Corporation | Process for depositing titanium nitride film by CVD |
US5344792A (en) * | 1993-03-04 | 1994-09-06 | Micron Technology, Inc. | Pulsed plasma enhanced CVD of metal silicide conductive films such as TiSi2 |
FR2707671A1 (en) * | 1993-07-12 | 1995-01-20 | Centre Nat Rech Scient | Method and device for introducing precursors into a chemical vapor deposition chamber. |
US5393564A (en) * | 1993-05-14 | 1995-02-28 | Micron Semiconductor, Inc. | High efficiency method for performing a chemical vapor deposition utilizing a nonvolatile precursor |
-
1996
- 1996-02-09 KR KR1019970705999A patent/KR100326744B1/en not_active IP Right Cessation
- 1996-02-09 WO PCT/US1996/001773 patent/WO1996027032A1/en active IP Right Grant
- 1996-02-09 JP JP52626896A patent/JP3787574B2/en not_active Expired - Fee Related
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1986006361A1 (en) * | 1985-04-26 | 1986-11-06 | Sri International | Preparing metal compounds, alloys and metals by pyrolysis |
US4970093A (en) * | 1990-04-12 | 1990-11-13 | University Of Colorado Foundation | Chemical deposition methods using supercritical fluid solutions |
US5300321A (en) * | 1992-05-12 | 1994-04-05 | Kawasaki Steel Corporation | Process for depositing titanium nitride film by CVD |
US5344792A (en) * | 1993-03-04 | 1994-09-06 | Micron Technology, Inc. | Pulsed plasma enhanced CVD of metal silicide conductive films such as TiSi2 |
US5393564A (en) * | 1993-05-14 | 1995-02-28 | Micron Semiconductor, Inc. | High efficiency method for performing a chemical vapor deposition utilizing a nonvolatile precursor |
FR2707671A1 (en) * | 1993-07-12 | 1995-01-20 | Centre Nat Rech Scient | Method and device for introducing precursors into a chemical vapor deposition chamber. |
Non-Patent Citations (1)
Title |
---|
ALBIN D S ET AL: "Spray pyrolysis processing of optoelectronic materials", ADVANCED CERAMIC MATERIALS, JULY 1987, USA, vol. 2, no. 3A, ISSN 0883-5551, pages 243 - 252, XP002003891 * |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8399056B2 (en) | 2006-06-02 | 2013-03-19 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Method of forming high-k dielectric films based on novel titanium, zirconium, and hafnium precursors and their use for semiconductor manufacturing |
US8470402B2 (en) | 2006-06-02 | 2013-06-25 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Method of depositing a metal-containing dielectric film |
US8668957B2 (en) | 2006-06-02 | 2014-03-11 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Method of forming dielectric films, new precursors and their use in semiconductor manufacturing |
US9583335B2 (en) | 2006-06-02 | 2017-02-28 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Method of forming dielectric films, new precursors and their use in semiconductor manufacturing |
US9911590B2 (en) | 2006-06-02 | 2018-03-06 | L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Methods of forming dielectric films, new precursors and their use in semiconductor manufacturing |
US10217629B2 (en) | 2006-06-02 | 2019-02-26 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Method of forming dielectric films, new precursors and their use in semiconductor manufacturing |
US9045509B2 (en) | 2009-08-14 | 2015-06-02 | American Air Liquide, Inc. | Hafnium- and zirconium-containing precursors and methods of using the same |
US9499571B2 (en) | 2014-12-23 | 2016-11-22 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Germanium- and zirconium-containing compositions for vapor deposition of zirconium-containing films |
US9663547B2 (en) | 2014-12-23 | 2017-05-30 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Silicon- and Zirconium-containing compositions for vapor deposition of Zirconium-containing films |
US9868753B2 (en) | 2014-12-23 | 2018-01-16 | L'Air Liquide, Société Anonyme our l'Etude et l'Exploitation des Procédés Georges Claude | Germanium- and zirconium-containing composition for vapor deposition of zirconium-containing films |
US10106568B2 (en) | 2016-10-28 | 2018-10-23 | L'Air Liquide, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Hafnium-containing film forming compositions for vapor deposition of hafnium-containing films |
Also Published As
Publication number | Publication date |
---|---|
KR19980702593A (en) | 1998-07-15 |
JP3787574B2 (en) | 2006-06-21 |
JPH10503242A (en) | 1998-03-24 |
KR100326744B1 (en) | 2002-06-20 |
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