WO2001044802A1 - Procede permettant de mesurer des composants chimiques gazeux dans un reacteur de processus destine au traitement de composants electriques, notamment de plaquettes - Google Patents

Procede permettant de mesurer des composants chimiques gazeux dans un reacteur de processus destine au traitement de composants electriques, notamment de plaquettes Download PDF

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Publication number
WO2001044802A1
WO2001044802A1 PCT/DE1999/004014 DE9904014W WO0144802A1 WO 2001044802 A1 WO2001044802 A1 WO 2001044802A1 DE 9904014 W DE9904014 W DE 9904014W WO 0144802 A1 WO0144802 A1 WO 0144802A1
Authority
WO
WIPO (PCT)
Prior art keywords
measurement
components
process chamber
reactor
process reactor
Prior art date
Application number
PCT/DE1999/004014
Other languages
German (de)
English (en)
Inventor
Gerald Rampf
Gunther Hoyer
Sven Schmidbauer
Original Assignee
Infineon Technologies Ag
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority to DE19826583A priority Critical patent/DE19826583A1/de
Application filed by Infineon Technologies Ag filed Critical Infineon Technologies Ag
Priority to PCT/DE1999/004014 priority patent/WO2001044802A1/fr
Publication of WO2001044802A1 publication Critical patent/WO2001044802A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B37/00—Lapping machines or devices; Accessories
    • B24B37/005—Control means for lapping machines or devices
    • B24B37/013—Devices or means for detecting lapping completion
    • 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
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/54—Controlling or regulating the coating process
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/0095—Semiconductive materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32917—Plasma diagnostics
    • H01J37/32935—Monitoring and controlling tubes by information coming from the object and/or discharge
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
    • H01L22/20—Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
    • H01L22/20—Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps
    • H01L22/26—Acting in response to an ongoing measurement without interruption of processing, e.g. endpoint detection, in-situ thickness measurement

Definitions

  • the present invention relates to a method for measuring gaseous chemical components in a process reactor for treating electrical components, in particular wafers, the process reactor having at least one process chamber in which the electrical components are treated.
  • the materials are usually deposited on the wafers at a relatively high pressure in the process chamber.
  • process reactors for example sputter reactors
  • the materials are usually deposited on the wafers at a relatively high pressure in the process chamber.
  • special devices which can also be used in the process pressure.
  • such devices have a complicated structure, so that they are particularly prone to failure, unfriendly and expensive.
  • these devices require a large amount of space and have only a low sensitivity. They are therefore not particularly suitable for long-term monitoring of the treatment processes.
  • Sensitivity are, for example, OIS mass spectrometers (open ion source mass spectrometers).
  • OIS mass spectrometers open ion source mass spectrometers
  • these mass spectrometers have the disadvantage that they cannot be used in the high process chamber pressure during the treatment process. For this reason, such OIS mass spectrometers have so far only been used for manual measurements at base pressure. Such measurements at base pressure are carried out, for example, when searching for leaks in the process chamber, such as helium leak detection.
  • the present invention is based on the object of developing a measuring method of the type mentioned at the outset in such a way that the disadvantages described are avoided.
  • a measurement method is to be provided with which precise measurements of gaseous chemical constituents can be carried out in a process reactor in a simple and cost-effective manner, so that long-term monitoring of the treatment process can also be carried out without any special effort and without special downtimes of the process reactor.
  • the object is achieved by developing a method of the type described at the outset, which according to the invention is characterized in that the measurement of the gaseous chemical constituents, in particular the chemical gas composition, is carried out in the process chamber via at least one residual gas analysis device, at least one residual gas Analysis device is connected to the process chamber, that the measurement of the gaseous chemical constituents takes place in-situ and that the in-situ measurement of the gaseous chemical constituents after completion of a treatment step of the electrical components in the process chamber, in particular between two successive treatment steps in the process chamber.
  • the measurement method according to the invention first of all ensures that the process reactor and treatment process control is carried out by event-related implementation of scheduled reactor maintenance and process stabilization via the in-situ measurement of the chemical components.
  • an automatic long-term control of the treatment processes can also be carried out with such residual gas analysis devices which, due to the principle, cannot measure at the prevailing process pressure.
  • the invention is based on the fundamental feature that the measurement of the chemical constituents via the residual gas analysis device is shifted to the period immediately after the treatment process in the process chamber.
  • the measurement takes place outside the treatment process and here in particular between two treatment steps.
  • a reproducible measurement signal is recorded during the decay curve of the treatment process, so that it can be clearly determined which chemical components are present in the process chamber.
  • the measurement can thus take place between two deposition phases in the process chamber. Due to the fact that the process pressure in the process chamber between two treatment steps is relatively low, it is also possible to use devices for measuring the chemical constituents which, although they have high measuring accuracy and sensitivity, are structurally inexpensive and relatively inexpensive, but because of the prevailing process pressure during the treatment process could not previously be used. Since the chemical components can be detected very well at low pressure, characterize treatment processes precisely with the measuring method according to the invention.
  • Preferred embodiments of the method according to the invention result from the jerk-related subclaims.
  • two or more process chambers can be provided in the process reactor.
  • the residual gas analysis device can be designed as a mass spectrometer, preferably as an OIS mass spectrometer.
  • mass spectrometers have a high measurement resolution and sensitivity. They have a compact, maintenance-friendly structure and are very few trouble-prone. They are therefore very cheap when generating optimal measurement results compared to the devices used previously.
  • the disadvantage described at the outset, namely that the OIS mass spectrometers cannot be used for measurement at process pressure, is irrelevant in the present case, since the measurement is carried out after the end of the treatment step and thus not at process pressure.
  • the in-situ measurement of the chemical constituents can be carried out by the residual gas analysis device by measuring the partial pressures of the gaseous chemical constituents.
  • the in-situ measurement of the chemical components in the process chamber is carried out at base pressure, preferably at a pressure less than IGT 4 Torr.
  • the treatment processes can be characterized very precisely since the chemical components and in particular possible contaminations can be easily detected at this low pressure.
  • the process reactor and / or the at least one residual gas analysis device can be connected to an evaluation unit.
  • the measured values of the gaseous chemical components are further processed in the evaluation unit.
  • special data records can be defined via the measured values, which are then stored in so-called trend files.
  • the measured values and the trend files can be used to make statements about the current process conditions and statements about process development over a longer period of time.
  • specific data of the process reactor can be processed further in the evaluation unit. Such data are, for example, data about the opening of certain valves, information about the general reactor condition or the like.
  • the evaluation unit can advantageously have a read memory or read / write memory.
  • the evaluation unit is preferably designed as a computer. In particular when using a computer, the metrological control of all residual gas analysis devices and the processing of the measured values can take place in the evaluation unit.
  • Communication between the evaluation unit and the process reactor is preferably carried out in the form of digital signals via an interface.
  • the measurement process of the residual gas analysis devices can be started or stopped.
  • the evaluation unit is preferably connected to a computer network.
  • Scheduled maintenance of the process reactor and stabilization of the treatment process are possible in a simple and inexpensive manner by means of the method according to the invention via the in-situ measurement of the chemical components.
  • the process reactor can be effectively protected against contamination by previous treatment steps.
  • the regeneration cycles Individual modules of the process reactor can be carried out event-related as required. Vacuum problems or problems with possible leaks can also be detected early by cyclical basic pressure measurement.
  • the measuring method according to the invention also enables new process dependencies to be found and the specific measurement data relating to the electrical components to be archived in a convenient manner for the purpose of quality assurance.
  • the method according to the invention is particularly preferably used in a process reactor for coating electrical components, in particular wafers.
  • a process reactor is, for example, a sputtering process reactor.
  • the method can also be applied to other electrical components and process reactors.
  • FIG. 1 shows the schematic structure of a process reactor for carrying out the method according to the invention.
  • Figure 1 is a to carry out a
  • Process reactor 10 trained sputtering method, in which 11 wafers in a coating device should be coated.
  • the wafers are coated by deposition in four process chambers 12 each.
  • Each of the process chambers 11 is connected via a valve 14 to a residual gas analysis device 13 designed as an OIS mass spectrometer.
  • the coating device 11 of the process reactor 10 is connected via lines 17 to an interface 16 and via the interface 16 to an evaluation unit 15 designed as a computer.
  • the interface 16 has the function of forwarding the specific data tapped from the process reactor 10 to the evaluation unit 15.
  • data can also be transmitted from the evaluation unit 15, for example alarm signals or signals for stopping the treatment process when limit data are exceeded, to the process reactor 10 via the interface.
  • the OIS mass spectrometers 13 are connected to a control device 18 via lines 19 and to the computer 15 via the control device 18.
  • the emission or the electron amplifier can be switched on and off via the control device 18.
  • OIS mass spectrometer 13 are connected via lines 21 to a data acquisition device 20 and via this to the computer 15.
  • the control device 18 and the data acquisition device 20 can also be part of the computer 15.
  • the lines 17, 19, 21 can be designed as electrical lines, optical lines or the like.
  • the chemical gas composition in the process chambers 12 is determined with the aid of the OIS mass spectrometer 13 at a base pressure of less than 10 ⁇ 4 Torr.
  • the OIS mass spectrometer 13 which could not otherwise be used at process pressure, can be used and the contamination due to the low pressure can be detected well.
  • the sputtering process can be characterized very precisely with the measuring method according to the invention.
  • the measurement control of all OIS mass spectrometers and the processing of the measurement values is carried out on the computer 15, on which a specific measurement and control software is installed. Communication between the computer 15 and the process reactor 10 takes the form of digital signals via the interface 16. With the aid of these signals, the measurement process of the individual OIS mass spectrometers 13 is started or stopped, depending on the state of the process reactor 10 and between two wafers.
  • the software installed in the computer 15 calculates from the ascertained raw data within a defined time window during the next deposition, mean value, maximum, minimum and standard deviation of the particle prints per wafer and creates a trend file therefrom. Each data point in the trend file corresponds to exactly one wafer, which means that data is recorded wafer-cyclically.
  • the development of various partial prints can be done from the trend file can be read over a longer period of time and the sputtering process can be characterized in this way.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Metallurgy (AREA)
  • Biochemistry (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Plasma & Fusion (AREA)
  • Food Science & Technology (AREA)
  • Medicinal Chemistry (AREA)
  • Materials Engineering (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Chemical Vapour Deposition (AREA)
  • Physical Vapour Deposition (AREA)

Abstract

La présente invention concerne un procédé permettant de mesurer des composants chimiques gazeux, notamment la composition chimique de gaz, dans un réacteur de processus (10) destiné au traitement de composants électriques, notamment de plaquettes. Un tel réacteur de processus peut être, par exemple, un réacteur de processus de pulvérisation cathodique. Le réacteur de processus selon cette invention présente au moins une chambre de processus (12), dans laquelle les composants électriques sont traités. L'objectif de la présente invention est d'effectuer des mesures précises de la composition chimique des gaz, de manière simple et économique, et, à l'aide de celles-ci, d'assurer un contrôle à long terme du réacteur de processus. Afin d'atteindre cet objectif, la mesure des composants chimiques gazeux est réalisée dans la chambre de processus, au moyen d'au moins un dispositif d'analyse des gaz résiduels (13), de préférence un spectromètre de masse OIS, au moins un dispositif d'analyse des gaz résiduels étant connecté à la chambre de processus. La mesure est de préférence réalisée à une pression de base. De plus, la mesure des composants chimiques gazeux est réalisée in-situ, directement après la fin d'une étape de traitement des composants électriques dans la chambre de processus, notamment entre deux étapes de traitement successives dans la chambre de processus.
PCT/DE1999/004014 1998-06-15 1999-12-16 Procede permettant de mesurer des composants chimiques gazeux dans un reacteur de processus destine au traitement de composants electriques, notamment de plaquettes WO2001044802A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
DE19826583A DE19826583A1 (de) 1998-06-15 1998-06-15 Verfahren zur Messung von gasförmigen chemischen Bestandteilen in einem Prozessreaktor zum Behandeln von elektrischen Bauelementen, insbesondere Wafern
PCT/DE1999/004014 WO2001044802A1 (fr) 1998-06-15 1999-12-16 Procede permettant de mesurer des composants chimiques gazeux dans un reacteur de processus destine au traitement de composants electriques, notamment de plaquettes

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19826583A DE19826583A1 (de) 1998-06-15 1998-06-15 Verfahren zur Messung von gasförmigen chemischen Bestandteilen in einem Prozessreaktor zum Behandeln von elektrischen Bauelementen, insbesondere Wafern
PCT/DE1999/004014 WO2001044802A1 (fr) 1998-06-15 1999-12-16 Procede permettant de mesurer des composants chimiques gazeux dans un reacteur de processus destine au traitement de composants electriques, notamment de plaquettes

Publications (1)

Publication Number Publication Date
WO2001044802A1 true WO2001044802A1 (fr) 2001-06-21

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PCT/DE1999/004014 WO2001044802A1 (fr) 1998-06-15 1999-12-16 Procede permettant de mesurer des composants chimiques gazeux dans un reacteur de processus destine au traitement de composants electriques, notamment de plaquettes

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DE (1) DE19826583A1 (fr)
WO (1) WO2001044802A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1103071A1 (fr) * 1998-07-24 2001-05-30 Leybold Inficon, Inc. Detection d'anomalies de processus non transitoires lors de processus d'usinage sous-vide

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19826583A1 (de) * 1998-06-15 2000-01-27 Siemens Ag Verfahren zur Messung von gasförmigen chemischen Bestandteilen in einem Prozessreaktor zum Behandeln von elektrischen Bauelementen, insbesondere Wafern
DE102005024010B4 (de) * 2005-05-20 2013-07-04 Schott Ag Beschichtungsanlage mit Einrichtungen für Prüf- und Serviceroutinen und Verfahren zum Durchführen von Prüf- und Serviceroutinen bei Beschichtungsanlagen
KR101141782B1 (ko) * 2007-05-15 2012-05-03 가부시키가이샤 아루박 질량 분석 유닛

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US5993165A (en) * 1994-10-31 1999-11-30 Saes Pure Gas, Inc. In Situ getter pump system and method
DE19826583A1 (de) * 1998-06-15 2000-01-27 Siemens Ag Verfahren zur Messung von gasförmigen chemischen Bestandteilen in einem Prozessreaktor zum Behandeln von elektrischen Bauelementen, insbesondere Wafern

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1103071A1 (fr) * 1998-07-24 2001-05-30 Leybold Inficon, Inc. Detection d'anomalies de processus non transitoires lors de processus d'usinage sous-vide
EP1103071A4 (fr) * 1998-07-24 2006-06-14 Leybold Inficon Inc Detection d'anomalies de processus non transitoires lors de processus d'usinage sous-vide

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Publication number Publication date
DE19826583A1 (de) 2000-01-27

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