JP2005090987A - Temperature rising desorption gas analyzer and analyzing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reliably measure the characteristics of a desorption gas of a halogen element by preventing the adsorption of the halogen element on the inner wall of a heating chamber. <P>SOLUTION: In this temperature rising desorption gas analyzer equipped with a load locking chamber 1 evacuated under vacuum and the heating chamber 11 for heating the sample fed from the load locking chamber 1 to raise the temperature thereof and measuring the characteristics of the desorption gas of the halogen element generated from the sample 21, the surface of the inner wall of the heating chamber 1 is coated with an aluminum sesquioxide film or a chromium sesquioxide film. By coating the inner wall of the heating chamber 11 with the aluminum sesquioxide film or the chromium sesquioxide film having high corrosion resistance, the adsorption of the halogen element (F, Cl, Br or the like) on the inner wall of the heating chamber is prevented when the sample is raised in temperature by heating and the characteristics of the desorption gas can be measured reliably. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  This invention can prevent the adsorption of halogen elements (F, Cl, Br, etc.) to the inner wall of the heating chamber when the sample is heated and heated, especially when the sample is heated and heated. The present invention relates to a temperature-programmed desorption gas analyzer capable of simultaneously measuring the previous sample pretreatment, the chemical bonding state of the sample surface and desorption gas characteristics while irradiating the sample surface with X-rays, and an analysis method using the same.

  A temperature-programmed desorption gas analyzer analyzes a gas released when a sample is heated in a vacuum using a mass spectrometer. Conventionally, this type of device is disclosed in “Vacuum, Vol. 34, No. 11, pages 813-819 (1991)”. By adopting a load lock method, outside air is directly introduced into the heating chamber. In this way, the influence of desorbed gas from the sample stage is suppressed, and the heating chamber can reach a vacuum level of 1E-7 Pa or less in a short time, and the desorbed gas from the sample can be measured with a mass spectrometer. .

  This measurement method is often used for the analysis of desorbed gas from semiconductor thin film materials. In particular, a laminated film or product sample extracted during or at the end of the semiconductor manufacturing process is set in a vacuum atmosphere and heated and heated. To do. As the temperature of the sample rises, a small amount of material adsorbed on the sample surface is released as a desorbed gas into the vacuum atmosphere, and the desorbed gas is measured with a mass spectrometer to identify the desorbed gas components. be able to.

  In addition, molecules and atoms with low adsorption heat in the temperature rising process, that is, with low desorption energy, are sequentially desorbed, and by analyzing the desorption spectrum with respect to the sample temperature, the amount of adsorbed molecules, the reaction process of adsorbed molecules, and the activation energy of desorption Etc. can be grasped.

  FIG. 11 shows a cross-sectional configuration diagram of a conventional temperature-programmed desorption gas analyzer. The load lock chamber 1 is connected to a valve 3 connected to a purge nitrogen cylinder 2 and a sample exchange port 4, and has a sample transport mechanism 5, and is connected to a turbo molecular pump 6 and a rotary pump 7. It has been evacuated. A vacuum gauge 8 is installed for measuring the degree of vacuum in the load lock chamber 1. The sample transport mechanism 5 can transfer the sample 9 from the load lock chamber 1 onto the heating stage 10. The heating chamber 11 is partitioned by a gate valve 12 and has a transparent quartz rod 13 and the heating stage 10. The transparent quartz rod 13 is provided with an infrared heating unit 14 for heating a sample, a temperature control device 15 and a computer 16. A turbo molecular pump 17 and a rotary pump 18 are connected to evacuate the heating chamber 11. A vacuum gauge 19 is installed to measure the degree of vacuum in the heating chamber 11. Further, a mass spectrometer 20 for measuring desorbed gas is connected.

  As shown in FIG. 11, a measurement sample 21 is set on the heating stage 10. When the degree of vacuum in the heating chamber 11 reaches 1E-7 Pa or less, sample heating is started. In this sample heating, infrared rays are irradiated from the back surface of the sample 21 through the transparent quartz rod 13 for introducing infrared rays, and the desorption gas released from the sample 21 as the sample is heated and heated is subjected to mass analysis. Measure in total 20.

Desorption gas analysis in electronic parts (gas filled electron tubes, crystal resonators, display panels, etc.) other than semiconductors is performed after the electronic parts are stored in an airtight chamber and then the chamber is evacuated and then In general, a method of forcibly releasing an enclosed gas in an electronic component by physically destroying the electronic component in the chamber and performing mass spectrometry on the released gas is known (for example, Patent Document 1).
JP 2001-349870 A

  However, in the conventional temperature-programmed desorption gas analyzer, when the desorption gas analysis is performed on the laminated film of the semiconductor thin film material shown in FIG. 12, if the silicon nitride film 22 that blocks the desorption gas exists on the outermost surface, There is a problem that the desorption gas from the fluorine-added silicon oxide film 24 formed on the silicon substrate 23 below the silicon nitride film 22 cannot be measured.

  Further, only the silicon nitride film 22 cannot be removed by a conventional method of physically destroying in a chamber. Even if the silicon nitride film 22 can be removed, the fluorine desorbed gas released from the fluorine-added silicon oxide film 24 is easily adsorbed on the inner wall of the heating chamber 11. Has issues that cannot be counted.

  This point will be described with reference to FIG. FIG. 13 shows a fluorine temperature-programmed desorption spectrum from the fluorine-added silicon oxide film 24 made of a single layer formed on the silicon substrate 23 on which the silicon nitride film 22 does not exist to a thickness of about 300 nm. When the fluorine-added silicon oxide film composed of this single layer is replaced with a new sample every measurement, the fluorine desorption gas is measured from the fluorine temperature-programmed desorption spectrum 25 of the first measurement to the fluorine temperature-programmed desorption spectrum 26 of the second measurement. It can be seen that the MS intensity of the fluorine desorption gas is increased by the fluorine temperature-programmed desorption spectrum 27 of the third measurement.

  As shown in FIG. 13, the fluorine desorption amount increases with each measurement, and it is assumed that the ion count in the mass spectrometer 20 is increased by the adsorption of fluorine gas on the inner wall of the heating chamber 11. The

  In addition, there was no method to simultaneously grasp the relationship between the activation energy of desorption from the film after sample surface treatment (cleaning, plasma treatment, etc.) and the energy with which molecules and atoms are chemically bonded on the sample surface. .

  Accordingly, an object of the present invention is made in view of the above problems, and in a temperature-programmed desorption gas analyzer for measuring a generated desorption gas component by heating and heating a sample in a vacuum chamber, Halogen elements (F, Cl, Br, etc.) adsorbed on the inner wall of the heating chamber can be prevented from being adsorbed, reliable desorption gas characteristics of halogen elements can be measured, sample pretreatment before heating / heating measurement, and sample To provide a temperature-programmed desorption gas analyzer and an analysis method capable of simultaneously measuring the chemical bonding state of a sample surface and desorption gas characteristics while irradiating the surface with X-rays.

  In order to solve the above problems, a temperature-programmed desorption gas analyzer according to claim 1 of the present invention includes a load-lock chamber that is evacuated and a heating chamber that heats and raises the temperature of a sample conveyed from the load-lock chamber. And a heated desorption gas analyzer for measuring desorption gas characteristics of a halogen element generated from the sample, wherein a surface of the inner wall of the heating chamber is a dialuminum trioxide film or a dichromium trioxide film. It is covered.

  The temperature-programmed desorption gas analyzer according to claim 2 is the temperature-programmed desorption gas analyzer according to claim 1, further comprising a control mechanism for controlling the inner wall temperature of the heating chamber.

  The temperature-programmed desorption gas analyzer according to claim 3 is the temperature-programmed desorption gas analyzer according to claim 1, wherein the leaked infrared rays are heated when the upper portion of the heating chamber is heated by irradiating infrared rays from the back of the sample. A quartz window was provided to prevent the generation of desorbed gas from the dialuminum trioxide film or the dichromium trioxide film.

  The temperature-programmed desorption gas analyzer according to claim 4 includes a load-lock chamber that is evacuated and a heating chamber that heats and raises the temperature of the sample conveyed from the load-lock chamber, and generates halogen generated from the sample. A temperature-programmed desorption gas analyzer for measuring desorption gas characteristics of an element, comprising a mechanism for scratching and peeling a surface layer of a sample inside the heating chamber.

  The temperature-programmed desorption gas analyzer according to claim 5 comprises a load-lock chamber that is evacuated and a heating chamber that heats and raises the temperature of the sample conveyed from the load-lock chamber, and the halogen generated from the sample. A temperature-programmed desorption gas analyzer for measuring desorption gas characteristics of an element, comprising a sample pretreatment chamber directly connected to the outside of the heating chamber, wherein the sample pretreatment chamber etches a surface layer of the sample With possible mechanisms.

  The temperature-programmed desorption gas analyzer according to claim 6 is the temperature-programmed desorption gas analyzer according to claim 5, wherein the sample pretreatment chamber includes a mechanism capable of chemically modifying the surface of the sample.

  The temperature-programmed desorption gas analyzer according to claim 7 is the temperature-programmed desorption gas analyzer according to claim 5, wherein the sample pretreatment chamber includes a mechanism capable of pattern-etching a film on the surface of the sample. It was.

  The temperature-programmed desorption gas analyzer according to claim 8 is the temperature-programmed desorption gas analyzer according to claim 4, 5 or 6, comprising an X-ray irradiation device focused inside the heating chamber, and heating the sample While equipped with a mechanism capable of simultaneously measuring the chemical bonding state and desorbed gas characteristics of the sample surface.

  The temperature-programmed desorption gas analysis method according to claim 9 is the temperature-programmed desorption gas analysis method using the temperature-programmed desorption gas analyzer according to claim 4, wherein the surface of the sample is formed inside the heating chamber. When the layer is scratched and peeled off, a peeling adhesive is applied to the surface of the sample, and after the surface coated with the peeling adhesive is rapidly frozen inside the heating chamber, the new surface of the peeled sample is measured. .

  The temperature-programmed desorption gas analysis method according to claim 10 is a temperature-programmed desorption gas analysis method using the temperature-programmed desorption gas analyzer according to claim 5, wherein the sample is directly connected to the outside of the heating chamber. When pattern-etching the film on the surface of the sample in the pretreatment chamber, the film that becomes the pattern for blocking the desorbed gas is left on the surface of the sample, and the desorbed gas from the portion without the pattern is measured. To do.

  According to the temperature-programmed desorption gas analyzer of claim 1 of the present invention, since the surface of the inner wall of the heating chamber is covered with the dialuminum trioxide film or the dichromium trioxide film, a reliable halogen element The desorption gas characteristics of can be measured. That is, by coating the inner wall of the heating chamber with a highly corrosion-resistant dialuminum trioxide film or dichromium trioxide film, a halogen element (F, Cl adsorbed on the inner wall of the heating chamber when the sample is heated and heated. , Br, etc.) can be prevented and reliable desorbed gas characteristics can be collected.

  According to the second aspect, since the control mechanism for controlling the inner wall temperature of the heating chamber is provided, the temperature of the sample to be heated and heated in the heating chamber can be controlled.

  According to a third aspect of the present invention, a quartz window for preventing generation of desorbed gas from the dialuminum trioxide film or the dichromium trioxide film due to leaked infrared rays at the time of heating by irradiating infrared rays from the back of the sample is provided at the upper part of the heating chamber. Therefore, infrared rays leaking from the sample can be transmitted through the quartz window. For this reason, desorption gas is prevented from being generated from the dialuminum trioxide film coated on the inner wall of the heating chamber.

  According to the temperature-programmed desorption gas analyzer of claim 4 of the present invention, since the heating chamber is provided with a mechanism for scratching and peeling the surface layer of the sample, the desorbed gas released from the sample surface is measured. In addition, the chemical bonding state spectrum can be measured by X-ray irradiation.

  According to the temperature-programmed desorption gas analyzer according to claim 5 of the present invention, the sample pretreatment chamber includes the sample pretreatment chamber directly connected to the outside of the heating chamber, and the sample pretreatment chamber has a mechanism capable of etching the surface layer of the sample. Since it is provided, the desorbed gas released from the sample surface can be measured, and the chemical bond state spectrum can be measured by X-ray irradiation.

  According to the sixth aspect of the present invention, since the sample pretreatment chamber has a mechanism capable of chemically modifying the surface of the sample, the sample pretreatment before heating / heating measurement and the chemistry of the sample surface while irradiating the sample surface with X-rays The bound state and desorbed gas characteristics can be measured.

  According to the seventh aspect of the present invention, since the sample pretreatment chamber has a mechanism capable of pattern-etching the film on the surface of the sample, measurement can be performed by releasing desorbed gas from a portion where there is no pattern.

  According to the eighth aspect of the present invention, an X-ray irradiation apparatus focused inside the heating chamber is provided, and a mechanism capable of simultaneously measuring the chemical bonding state and desorption gas characteristics of the sample surface while heating the sample is provided. While irradiating X-rays, the chemical bonding state of the sample surface and the desorbed gas characteristics can be measured simultaneously.

  According to the temperature-programmed desorption gas analysis method according to claim 9 of the present invention, when the surface layer of the sample is scratched and peeled inside the heating chamber, a peeling adhesive is applied to the surface of the sample, and inside the heating chamber, Since the new surface of the peeled sample is measured after rapidly freezing the surface to which the peeling adhesive is applied, the chemical bonding state of the sample surface and the desorbed gas characteristics can be measured simultaneously. It is particularly effective for interfacial peeling between a metal film and a nonmetal film.

  According to the temperature-programmed desorption gas analysis method of claim 10 of the present invention, when the film on the surface of the sample is pattern-etched in the sample pretreatment chamber directly connected to the outside of the heating chamber, the desorption is performed on the surface of the sample. Measures the desorption gas from the part without the pattern, leaving the film to be a pattern for blocking the degassing, so the sample pretreatment before heating / heating measurement, the chemical bonding state of the sample surface, desorption Gas characteristics can be measured simultaneously.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, in the cross-sectional block diagram of the thermal desorption gas analyzer concerning each embodiment, the same code | symbol is attached | subjected about the same component.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional configuration diagram of a temperature programmed desorption gas analyzer according to a first embodiment of the present invention.

  As shown in FIG. 1, a temperature-programmed desorption gas analyzer according to an embodiment of the present invention includes a load-lock chamber 1 that has been evacuated and a heating chamber that heats and raises the temperature of a sample conveyed from the load-lock chamber 1. 11 and the desorption gas characteristic of the halogen element generated from the sample is measured.

  The load lock chamber 1 is connected to a valve 3 connected to a purge nitrogen cylinder 2 and a sample exchange port 4, and has a sample transport mechanism 5, and is connected to a turbo molecular pump 6 and a rotary pump 7. It has been evacuated. A vacuum gauge 8 is installed for measuring the degree of vacuum in the load lock chamber 1. The sample transport mechanism 5 can transfer the sample 9 from the load lock chamber 1 onto the heating stage 10. The heating chamber 11 is partitioned by a gate valve 12 and has a transparent quartz rod 13 and the heating stage 10. The transparent quartz rod 13 is provided with an infrared heating unit 14 for heating a sample, a temperature control device 15 and a computer 16. A turbo molecular pump 17 and a rotary pump 18 are connected to evacuate the heating chamber 11. A vacuum gauge 19 is installed to measure the degree of vacuum in the heating chamber 11. Further, a mass spectrometer 20 for measuring desorbed gas is connected.

  A measurement sample 21 is set on the heating stage 10 using the sample transport mechanism 5. Before heating and heating the sample 21, the gate valve 28 is opened, and the sample surface film of the sample 21 is scratched and peeled off by using a film peeling mechanism 29. The sample surface film is scratched and peeled off. The scratch-separated film is dropped and collected through the sample disposal slope 30 into the sample disposal chamber 31 evacuated by the turbo molecular pump 6 and the rotary pump 7. Then, the X-ray gun 32 is used to irradiate the nascent surface of the sample 21 that has been peeled off, and the photoelectrons generated from the nascent surface are detected by the electron spectrometer 33 to measure the chemical bond state spectrum. To do. At this time, since the surface composition of this new surface is also known, it is possible to grasp the scratch peeling state of the sample surface film of the sample 21.

  Then, the gate valve 28 is closed, and the sample heating is started when the degree of vacuum in the heating chamber 11 reaches 1E-7 Pa or less. In this sample heating, infrared rays are irradiated from the back surface of the sample 21 through the transparent quartz rod 13 for introducing infrared rays, and the desorbed gas released from the sample 21 as the sample is heated and heated is measured by the mass spectrometer. 20 and the X-ray irradiation by the X-ray gun 32 and the electron spectrometer 33 are used to measure the chemical bonding state spectrum of the sample surface.

  Here, another membrane peeling method in the temperature-programmed desorption gas analyzer according to the first embodiment will be described. Before the sample 9 is introduced into the sample exchange window 4, the sample 9 is exposed to the atmosphere in the atmosphere. Then, the epoxy adhesive is applied and dried, and the sample 9 coated with the adhesive is set in the load lock chamber 1. When the degree of vacuum in the load lock chamber 1 reaches 1E-5 Pa or less, the gate valve 12 is opened and the sample transport mechanism 5 is used to place the sample 9 on the heating stage 10 in the heating chamber 11. Transfer. A copper quick freezing bar 34 is brought into contact with the transferred sample surface, and liquid nitrogen is injected into the quick freezing bar 34 to shrink and harden the adhesive on the surface of the sample. Remove the film on the sample surface by scratching. Then, the sample heating is started, the desorbed gas released from the sample surface is measured by the mass spectrometer 20, and the chemical bond state spectrum is measured by the X-ray irradiation by the X-ray gun 32 and the electron spectrometer 33. It is a method to measure simultaneously.

  FIG. 2 is a schematic diagram showing a scratch-peeled state of a sample surface to which an adhesive is applied when the temperature-programmed desorption gas analyzer according to the first embodiment of the present invention is used. In the sample of FIG. 2, a carbon-added silicon oxide film 36 having a film thickness of about 300 nm is formed on a silicon substrate 35, and a copper film 37 having a film thickness of about 500 nm is further formed thereon. Then, an epoxy adhesive 38 is applied and dried on the copper film 37, and the adhesive 38 is shrink-hardened in the heating chamber 11 using the quick freezing rod 34 cooled with liquid nitrogen. After that, the interface between the copper film 37 and the carbon-added silicon oxide film 36 is scratched and peeled off with a diamond blade 39 mounted at the tip of the film peeling mechanism 29. In particular, it has been confirmed that the scratch peeling method using liquid nitrogen is effective for peeling an interface between a metal film and a non-metal film.

  A second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a cross-sectional configuration diagram of the temperature-programmed desorption gas analyzer according to the second embodiment of the present invention.

  As shown in FIG. 3, the temperature-programmed desorption gas analyzer according to the embodiment of the present invention includes the first embodiment, a load lock chamber 1, and a heating chamber 11. In addition, a sample pretreatment chamber directly connected to the outside of the heating chamber 11 is provided, and the sample pretreatment chamber has a mechanism capable of etching the surface layer of the sample. In this case, the sample pretreatment chamber is a load lock chamber 1 that also serves as dry etching.

  The load lock chamber 1 is connected to a valve 3 connected to a purge nitrogen cylinder 2 and an etching cylinder 40 and a sample exchange port 4, and has a sample transport mechanism 5. A rotary pump 7 is connected and evacuated. A vacuum gauge 8 is installed for measuring the degree of vacuum in the load lock chamber 1. The sample transport mechanism 5 can transfer the sample 9 from the load lock chamber 1 onto the cathode electrode 41 or the heating stage 10. Then, the sample 9 is transferred onto the cathode electrode 41 using the sample transport mechanism 5. A matching box 44 performs matching between the cathode electrode 41 and the anode electrode 42 by the power applied from the high frequency power source 43, plasma is generated in the chamber, and the surface of the sample 45 on the cathode electrode 41 is etched. . After the etching is completed, the sample 45 etched by opening the gate valve 12 is transferred onto the heating stage 10 of the heating chamber 11 by the sample transport mechanism 5. Then, the heated sample 21 is heated using the transparent quartz rod 13, the infrared heating unit 14, the temperature controller 15, and the computer 16. The desorption gas released from the sample surface is measured by the mass spectrometer 20 and the X-ray gun 32 irradiates the sample surface with X-rays, and the chemical spectrometer 33 measures the chemical bond state spectrum.

  Next, FIG. 4 is a nitrogen temperature-programmed desorption spectrum when using a temperature-programmed desorption gas analyzer according to the second embodiment of the present invention, and FIG. 5 is a temperature-programmed temperature according to the second embodiment of the present invention. It is a silicon chemical bond state spectrum when using a desorption gas analyzer. The measurement sample of FIGS. 4 and 5 is a silicon oxide film having a thickness of about 300 nm formed on a silicon substrate. After the sample is subjected to nitrogen plasma treatment on the cathode electrode 41 in FIG. 3, the sample is transferred onto the heating stage 10 of the heating chamber 11 and heating / heating is started. Spectra and chemical bonding state spectra were measured.

  4 and 5, the nitrogen temperature-programmed desorption spectrum 47 after the nitrogen plasma treatment shows a large nitrogen at peak top temperature (Tp) of 360 ° C. as compared with the nitrogen temperature-programmed desorption spectrum 46 before the nitrogen plasma treatment. Desorbed gas is generated. Further, in the chemical bonding state spectrum, the peak top energy (about about 103.5 eV) of the silicon chemical bonding state spectrum 49 after the nitrogen plasma processing is compared with the peak top energy (about 103.5 eV) of the silicon chemical bonding state spectrum 48 before the nitrogen plasma processing. 103.3 eV) shows almost no chemical energy shift. That is, it can be seen that the silicon oxide film surface is in a silicon oxide state regardless of the nitrogen plasma treatment.

  FIG. 6 is an Arrhenius plot for the nitrogen plasma treatment after using the temperature programmed desorption gas analyzer according to the second embodiment of the present invention. ) To obtain the peak top temperature (Tp) of the nitrogen desorption gas, and an Arrhenius plot 50 was created.

  Here, the activation energy of nitrogen elimination 0.62 eV (Ea) is the bond dissociation energy between two atoms in the presence of a chemical bond state between silicon and nitrogen 4.6 eV (reference: edited by Chemical Society of Japan, Compared to “Chemical Handbook”, p976 Maruzen (1993), it was confirmed to be much smaller. That is, it is presumed that nitrogen existing on the surface of the silicon oxide film after the nitrogen plasma treatment is likely to exist on the surface of the silicon oxide film as a single molecule without being bonded to other atoms.

  A third embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a cross-sectional configuration diagram of a temperature-programmed desorption gas analyzer according to the third embodiment of the present invention.

  As shown in FIG. 7, the temperature-programmed desorption gas analyzer of the present invention includes a load lock chamber 1 and a heating chamber 11 as in the first embodiment. Further, as a sample pretreatment, a gas phase chemical etching chamber 51 connected to the load lock chamber 1 is provided.

  In the upper part of the gas phase chemical etching chamber 51, there is a shower head 52 to which hydrofluoric acid vapor is jetted. The shower head 52 is connected to a hydrofluoric acid bottle 53 and a washing water bottle 54, and has a steam injection valve 55 and a nitrogen introduction valve 56. The load lock chamber 1 is evacuated by connecting a turbo molecular pump 6 and a rotary pump 7. A vacuum gauge 8 is installed for measuring the degree of vacuum in the load lock chamber 1.

  The sample transfer of the sample 9 using the sample transport mechanism 5 can be transferred from the gas phase chemical etching chamber 51 to the load lock chamber 1 or the heating stage 10 of the heating chamber 11. Then, the sample 9 is transferred onto the chemical etching stage 57 using the sample transport mechanism 5. Then, the surface of the sample 45 is chemically etched by opening the valve 58 and the valve 55 of the hydrofluoric acid bottle 53 and filling the vapor-phase chemical etching chamber 51 with the hydrofluoric acid vapor through the shower head 52. Cleaning the chemically etched sample 45 closes the valve 58 and opens the valve 59 of the cleaning water bottle 54 to clean the sample surface. The cleaning water used in the gas phase chemical etching chamber 51 is discharged to the drain. After cleaning, the sample is dried by closing the valve 55 and opening the valve 56 to introduce nitrogen into the gas phase chemical etching chamber 51 and dry it. After the sample is dried, the gate valve 60 is opened, and the sample 45 is transferred to the load lock chamber 1 using the sample transport mechanism 5.

  When the degree of vacuum in the load lock chamber 1 reaches 1E-5 Pa or less, the gate valve 12 is opened and the sample 45 is transferred onto the heating stage 10 in the heating chamber 11 using the sample transport mechanism 5. Included. Then, sample heating of the chemically etched sample 21 is started using the transparent quartz rod 13, the infrared heating unit 14, the temperature control device 15, and the computer 16. The desorption gas released from the sample surface is measured by the mass spectrometer 20 and the X-ray gun 32 irradiates the sample surface with X-rays, and the chemical spectrometer 33 measures the chemical bond state spectrum.

  Incidentally, the inner wall surface of the heating chamber 11 is covered with a dialuminum trioxide film, and a heater 61 for heating the inner wall of the heating chamber 11 is also provided. Further, infrared light is irradiated on the back surface of the sample 21 through the transparent quartz rod 13, and the infrared light leaking from the sample 21 is irradiated on the inner wall upper portion of the heating chamber 11. Since there is a possibility that desorbed gas is generated from the coated dialuminum trioxide film, a quartz window 62 that transmits infrared rays is also provided at the top of the heating chamber 11.

  The reason why a dialuminum trioxide film is selected as the inner wall material of the heating chamber 11 is that it is highly corrosion resistant to halogen-based gas plasma (reference: edited by Japan Air Cleaning Association, “Air Cleaning”, Vol. 39, No. 5, p10 (2002)). In particular, a chemically modified sample measures a halogen-based gas. Therefore, the heating chamber 11 covered with a highly corrosive-resistant dialuminum trioxide film is used, and the inner wall of the heating chamber 11 is covered with the heater 61. It is considered that heating at about 60 ° C. or higher is effective in preventing adsorption of the halogen-based gas to the inner wall of the chamber.

  Next, FIG. 8 is a phosphorus temperature programmed desorption spectrum when using the temperature programmed desorption gas analyzer according to the third embodiment of the present invention. The measurement sample of FIG. 8 is a phosphorus-doped polycrystalline silicon film having a thickness of about 100 nm formed on a silicon substrate, and a silicon oxide film having a thickness of about 10 nm is deposited on the surface of the sample. After the chemical etching process is performed on the surface of the sample at the chemical etching stage 57 in FIG. 7, the sample is transferred onto the heating stage 10 of the heating chamber 11 and heating / heating is started. The spectrum was measured. As shown in FIG. 8, in the phosphorus temperature-programmed desorption spectrum 64 after the chemical etching process, phosphorus desorption gas is generated from around 700 ° C. as compared with the phosphorus temperature-programmed desorption spectrum 63 before the chemical etching process.

  FIG. 9 is a schematic diagram of the pattern etching process when using the temperature programmed desorption gas analyzer according to the third embodiment of the present invention. Referring to FIG. 9, this sample is a phosphorus-doped polycrystalline silicon film 66 formed on a silicon substrate 65, and an ultrathin silicon oxide film 67 is deposited on the sample surface. Inside the chemical etching stage 57, the sample surface is covered with a patterned polytetrafluoroethylene (PTFE) mask 68 as shown in FIG. In FIG. 9B, the sample surface is subjected to pattern etching. After the removal of the mask 68, phosphorus desorption gas can be selectively measured from a portion having no pattern as shown in FIG.

  FIG. 10 is a fluorine temperature-programmed desorption spectrum when using the temperature-programmed desorption gas analyzer according to the third embodiment of the present invention. The measurement sample of FIG. 10 is an added silicon oxide film having a thickness of about 300 nm and having a different fluorine concentration formed on a silicon substrate, and a silicon nitride film having a thickness of about 10 nm is deposited on the surface of each sample. After the sample is dry-etched on the cathode electrode 41 of FIG. 3, the sample is transferred onto the heating stage 10 of the heating chamber 11 of FIG. The temperature programmed desorption spectrum of the sample was measured.

  From FIG. 10, there is no change in the MS intensity of the high concentration fluorine temperature programmed desorption spectrum 69 of the first measurement and the high concentration fluorine temperature programmed desorption spectrum 70 of the second measurement, and the low concentration fluorine temperature desorption of the first measurement. It was confirmed that there was no change in the MS intensity of the separation spectrum 71 and the high concentration fluorine temperature programmed desorption spectrum 72 of the second measurement. That is, since the inner wall of the heating chamber 11 is coated with a highly corrosion-resistant dialuminum trioxide film, a reliable temperature programmed desorption spectrum of halogen elements (F, Cl, Br, etc.) can be measured. .

  Here, in the present embodiment, by using the temperature-programmed desorption gas analyzer configured as described above, the halogen elements (F, Cl, Br, etc.) adsorbed on the inner wall of the heating chamber are prevented from being adsorbed, and a reliable halogen is used. Desorption gas characteristics of elements can be measured. Moreover, the ability to simultaneously measure the sample pretreatment before heating / temperature rise measurement, the chemical bonding state of the sample surface while irradiating the sample surface with X-rays, and the desorption gas characteristics is limited to the mode described in the above embodiment. It is not a thing. In the first and second embodiments, the surface of the inner wall of the heating chamber 11 may be covered with a dialuminum trioxide film or a dichromium trioxide film as in the third embodiment.

  The temperature-programmed desorption gas analyzer and the analysis method according to the present invention prevent the adsorption of halogen elements (F, Cl, Br, etc.) to the inner wall of the heating chamber, and perform sample pretreatment before heating / temperature measurement. It is possible to measure the chemical bonding state of the sample surface and the desorption gas characteristics at the same time while irradiating the sample surface with X-rays. The present invention can be applied to a temperature-programmed desorption gas analyzer capable of simultaneously measuring the state and desorption gas characteristics and its analysis method.

1 is a cross-sectional configuration diagram of a temperature-programmed desorption gas analyzer according to a first embodiment of the present invention. It is a schematic diagram of the scratch peeling state in the 1st Embodiment of this invention. It is a cross-sectional block diagram of the temperature-programmed desorption gas analyzer in the 2nd Embodiment of this invention. It is a nitrogen temperature-programmed desorption spectrum figure in the 2nd Embodiment of this invention. It is a silicon chemical bond state spectrum figure in a 2nd embodiment of the present invention. It is an Arrhenius plot figure in the 2nd Embodiment of this invention. It is a cross-sectional block diagram of the temperature rising desorption gas analyzer in the 3rd Embodiment of this invention. It is a phosphorus temperature programmed desorption spectrum figure in the 3rd embodiment of the present invention. It is a schematic diagram of the pattern etching process in the 3rd Embodiment of this invention. It is a fluorine temperature-programmed desorption spectrum in the third embodiment of the present invention. It is a cross-sectional block diagram of the temperature-programmed desorption gas analyzer in a prior art. It is sectional drawing of the laminated film of the semiconductor thin film material in a prior art. It is a fluorine temperature-programmed desorption spectrum diagram in the prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Load lock chamber 2 Nitrogen cylinder 3,55,56,58,59 Valve 4 Sample exchange port 5 Sample conveyance mechanism 6,17 Turbo molecular pump 7,18 Rotary pump 8,19 Vacuum gauge 9,21,45 Sample 10 Heating stage DESCRIPTION OF SYMBOLS 11 Heating chamber 12, 28, 60 Gate valve 13 Transparent quartz rod 14 Infrared heating unit 15 Temperature control device 16 Computer 20 Mass spectrometer 29 Membrane peeling mechanism 30 Sample disposal slope 31 Sample disposal chamber 32 X-ray gun 33 Electron spectrometer 40 Etching Gas cylinder 41 Cathode electrode 42 Anode electrode 43 High frequency power supply 44 Matching box 51 Gas phase chemical etching chamber 52 Shower head 53 Hydrofluoric acid bottle 54 Washing water bottle 57 Chemical etching stage 61 Heater 62 Quartz window

Claims (10)

  A temperature-programmed desorption gas comprising a load-lock chamber evacuated and a heating chamber that heats and raises the temperature of a sample conveyed from the load-lock chamber, and measures a desorption gas characteristic of a halogen element generated from the sample A temperature-programmed desorption gas analyzer, characterized in that the inner wall surface of the heating chamber is covered with a dialuminum trioxide film or a dichromium trioxide film.   The temperature-programmed desorption gas analyzer according to claim 1, further comprising a control mechanism that controls the inner wall temperature of the heating chamber.   A quartz window for preventing generation of desorbed gas from the dialuminum trioxide film or dichromium trioxide film due to leaked infrared rays when heating by irradiating infrared rays from the back surface of the sample is provided at the upper part of the heating chamber. The temperature-programmed desorption gas analyzer according to 1.   A temperature-programmed desorption gas comprising a load-lock chamber evacuated and a heating chamber that heats and raises the temperature of a sample conveyed from the load-lock chamber, and measures a desorption gas characteristic of a halogen element generated from the sample A temperature-programmed desorption gas analyzer comprising a mechanism for scratching and peeling a surface layer of a sample inside the heating chamber.   A temperature-programmed desorption gas comprising a load-lock chamber evacuated and a heating chamber that heats and raises the temperature of a sample conveyed from the load-lock chamber, and measures a desorption gas characteristic of a halogen element generated from the sample A temperature-programmed desorption gas analyzer comprising a sample pretreatment chamber directly connected to the outside of the heating chamber, the sample pretreatment chamber having a mechanism capable of etching a surface layer of the sample.   6. The thermal desorption gas analyzer according to claim 5, wherein the sample pretreatment chamber includes a mechanism capable of chemically modifying the surface of the sample.   6. The thermal desorption gas analyzer according to claim 5, wherein the sample pretreatment chamber includes a mechanism capable of pattern-etching a film on the surface of the sample.   The X-ray irradiation apparatus focused inside the heating chamber is provided, and a mechanism capable of simultaneously measuring the chemical bonding state and desorption gas characteristics of the sample surface while heating the sample is provided. Thermal desorption gas analyzer.   5. A temperature-programmed desorption gas analysis method using the temperature-programmed desorption gas analyzer according to claim 4, wherein when the surface layer of the sample is scratched and peeled inside the heating chamber, the adhesion to the sample surface is peeled off. A temperature-programmed desorption gas analysis method characterized by measuring a new surface of a sample peeled after applying a coating agent, rapidly freezing the surface coated with the peeling adhesive inside the heating chamber.   6. A temperature-programmed desorption gas analysis method using the temperature-programmed desorption gas analyzer according to claim 5, wherein a film on the surface of the sample is subjected to pattern etching in a sample pretreatment chamber directly connected to the outside of the heating chamber. In this case, a temperature-programmed desorption gas analysis method is characterized in that a film having a pattern for blocking desorption gas is left on the surface of the sample, and desorption gas from a portion without the pattern is measured.

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