JP3810303B2 - Thin film inspection method and apparatus, and micro device manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thin film inspection method and apparatus for inspecting a sample containing a thin film using Rutherford backscattering spectroscopy (hereinafter also referred to as RBS), and a microdevice using the thin film inspection method. It relates to a manufacturing method.
[0002]
[Prior art]
In recent years, with the improvement in the surface recording density of hard disk devices, there has been a demand for improved performance of thin film magnetic heads. The thin film magnetic head has a structure in which a reproducing head having a magnetoresistive effect element for reading (hereinafter also referred to as MR (Magneto-resistive) element) and a recording head having an inductive electromagnetic transducer for writing are laminated. Composite thin film magnetic heads are widely used.
[0003]
By the way, the MR element is formed, for example, by forming an MR film having a magnetoresistive effect and selectively etching the MR film using a patterned resist layer as a mask. The lead layer connected to the MR element is formed by, for example, a lift-off method or an etching method using a patterned resist layer as a mask.
[0004]
When forming the MR element and the lead layer, an oxide layer is formed on the surface of the thin film constituting the MR element and the lead layer by various processes such as film formation by sputtering, etching, resist layer peeling, and annealing. Is done. In addition, a new thin film may be formed on this oxide layer, and an oxide layer may exist between two adjacent thin films.
[0005]
The oxide layer as described above greatly affects the characteristics of the read head. Therefore, in order to stably manufacture a reproducing head having excellent characteristics, it is necessary to grasp the state of the oxide layer and appropriately process it in the manufacturing process of the reproducing head. Therefore, it is necessary to inspect the oxide layer formed during the manufacturing process of the thin film magnetic head.
[0006]
As a method for inspecting an oxide layer existing on the surface of a thin film or between two adjacent thin films, Auger electron spectroscopy (hereinafter referred to as AES), X-ray photoelectron spectroscopy (hereinafter referred to as XPS), A method of performing surface analysis using secondary ion mass spectrometry (hereinafter referred to as SIMS), a fluorescent X-ray spectroscopic analysis method (hereinafter referred to as XRF), an X-ray diffraction method (hereinafter referred to as XRD). Etc.) and the like, and a method of performing composition analysis and crystal analysis can be considered.
[0007]
In addition to the above methods, as a method for inspecting an oxide layer, a laminated structure inspection method using an X-ray reflectivity measuring apparatus as disclosed in JP-A-2001-83108, or JP-A-7-190961 A method using RBS as shown in the publication can be considered.
[0008]
On the other hand, "" Analysis technology of the extreme surface area by the high-resolution Rutherford backscattering analysis method ", Koverunikus Vol.8, OCT.1999, p4-5" and "Kimura et al." “Development,” Surface Science Vol. 22, No. 7, 2001, p21 to 27, discloses a technique of high-resolution RBS (hereinafter referred to as “high-resolution RBS”). This high resolution RBS achieves a high resolution of about 0.2 nm by using a medium energy region He ion beam and a magnetic field type energy analyzer.
[0009]
[Problems to be solved by the invention]
A method for performing surface analysis using AES, XPS, or the like requires an ultra-high vacuum state. This method is a destructive inspection method. That is, in this method, the composition distribution in the depth direction of the sample is measured while gradually removing the sample by etching using Ar gas ions or the like. Further, it takes a lot of time to measure the composition distribution. For these reasons, in applications where the oxide layer is inspected during the manufacturing process of the thin film magnetic head, the method of inspecting the oxide layer by surface analysis is used only in a limited case, such as when inspecting simultaneously with etching. I can't.
[0010]
In AES and XPS, the range of the depth at which an element can be detected varies depending on the element and is approximately 2 nm to 10 nm. Therefore, it is difficult for AES or XPS to detect only a very thin oxide layer present on the surface of the thin film.
[0011]
On the other hand, in the thin film inspection method using XRF or XRD, since the X-ray penetration depth is large, information on the substance in the entire thin film is detected. Therefore, in this inspection method, it is not possible to distinguish between an oxide layer existing on the surface of the thin film and an oxide layer existing between two adjacent thin films. Therefore, this inspection method cannot detect the thickness of the oxide layer and the position of the oxide layer in the thickness direction of the thin film.
[0012]
In addition, the laminated structure inspection method using an X-ray reflectivity measuring apparatus as disclosed in Japanese Patent Application Laid-Open No. 2001-83108 has no diffusion layer at the interface between two adjacent thin films. It can only be applied to laminates where reflection occurs. Therefore, in this method, when a non-uniform oxide layer having a thickness of several atomic layers exists between two adjacent thin films, this oxide layer may not be detected.
[0013]
Further, in the conventional RBS, the depth resolution is about 10 nm. Therefore, it is difficult to detect an extremely thin oxide layer or to accurately detect the position of the oxide layer in the thickness direction of the oxide layer and the thin film.
[0014]
On the other hand, if the above-described high resolution RBS capable of realizing a high resolution of about 0.2 nm is used, an extremely thin oxide layer can be detected, or the position of the oxide layer in the thickness direction of the oxide layer and the thin film can be determined. It becomes possible to detect with high accuracy.
[0015]
Conventionally, as an analysis method of a laminated structure using RBS, there is an analysis method using spectrum simulation as disclosed in Japanese Patent Application Laid-Open Nos. 7-190961 and 5-157710. In this analysis method, a theoretical spectrum is calculated assuming a plurality of layers from the surface to the inside of the sample. Then, the spectrum obtained by actual measurement is compared with the theoretical spectrum, and the element density of each layer is corrected so that the difference between the two becomes small.
[0016]
However, this analysis method has a problem that a complicated calculation must be repeatedly executed, and a long processing time is required. Therefore, this analysis method is not suitable for an application in which an oxide layer is inspected during the manufacturing process of a thin film magnetic head.
[0017]
The various problems described above are not limited to the case where the oxide layer is inspected, but are generally applicable to the case where a layer having a different composition (hereinafter referred to as a heterogeneous layer) adjacent to a thin film having a known composition is inspected. . In addition to the oxide layer, the different layer includes, for example, a layer formed by depositing a substance removed from the base on the thin film when the thin film and the base are etched.
[0018]
Further, when inspecting an oxide layer formed during the manufacturing process of a thin film magnetic head, there are the following problems. In other words, in order to inspect the oxide film formed on the surface of the sample during processing such as sputtering and etching, when the sample is taken out of the processing chamber and exposed to the atmosphere, an oxide layer is formed on the surface of the sample due to natural oxidation. End up. As a result, it is impossible to determine whether the oxide layer present on the surface of the sample is formed during the processing or after the processing.
[0019]
The above problems also apply to the case of inspecting different layers formed during the manufacturing process of micro devices other than the thin film magnetic head. A micro device refers to a small device manufactured using a thin film forming technique. Examples of micro devices include semiconductor devices, sensors and actuators using thin films, in addition to thin film magnetic heads.
[0020]
The present invention has been made in view of such problems, and a first object thereof is a thin film inspection method capable of easily and accurately inspecting a thin film having a known composition and a structure in the vicinity thereof. And providing an apparatus.
[0021]
In addition, a second object of the present invention is to easily and accurately inspect a thin film having a known composition and a structure in the vicinity thereof during the manufacturing process of a microdevice including the thin film having a known composition. An object of the present invention is to provide a method of manufacturing a microdevice that can be made.
[0022]
[Means for Solving the Problems]
The thin film inspection method of the present invention is a method for inspecting a thin film in a sample including a thin film having a known composition and a structure in the vicinity thereof,
A procedure for measuring the energy spectrum of backscattered ions by Rutherford backscattering spectroscopy under a predetermined condition for a sample;
Assuming a virtual thin film with a known composition, the energy spectrum of backscattered ions obtained by Rutherford backscattering spectroscopy is determined by simulation for this virtual thin film under the same conditions as those for the sample. And the steps to
Obtaining a spectrum of the difference between the energy spectrum determined by simulation and the measured energy spectrum;
And a procedure for analyzing the structure of the thin film and its vicinity based on the spectrum of the difference.
[0023]
In this thin film inspection method, a spectrum of a difference between an energy spectrum determined by simulation for a virtual thin film having a known composition and an energy spectrum measured for a sample is obtained, and the thin film and its vicinity are calculated based on the spectrum of the difference. The structure of is analyzed.
[0024]
In the thin film inspection method of the present invention, the analyzing procedure may detect a different layer adjacent to the thin film and having a composition different from that of the thin film, based on the difference spectrum. In this case, the analyzing procedure may further detect the thickness of the different layer and the position of the different layer in the thickness direction of the thin film based on the difference spectrum.
[0025]
In the thin film inspection method of the present invention, the energy spectrum of the sample is measured by irradiating the sample with ions having an energy in the range of 250 to 500 keV, and the ions backscattered by the sample are subjected to magnetic field type energy analysis. The ion may be dispersed according to energy by a detector, and the dispersed ions may be detected by a one-dimensional position detector.
[0026]
In addition, the thin film inspection method of the present invention further includes a first thin film having a known composition and a known composition directly before or on the first thin film, before the procedure of measuring the energy spectrum of the sample. You may provide the procedure which produces the sample containing the 2nd thin film formed through the different layer.
[0027]
The thin film inspection apparatus of the present invention is an apparatus for inspecting a thin film in a sample including a thin film having a known composition and a structure in the vicinity thereof,
A measuring device for measuring the energy spectrum of backscattered ions of a sample by Rutherford backscattering spectroscopy;
Information on the energy spectrum measured by the measuring device under a predetermined condition is input for the sample, and a virtual thin film having a known composition is assumed, and this virtual thin film has the same conditions as the measurement for the sample. The energy spectrum of backscattered ions obtained by Rutherford backscattering spectroscopy under conditions is determined by simulation, and the spectrum of the difference between the energy spectrum determined by simulation and the measured energy spectrum is obtained. And a control device for generating information on the thin film and the structure in the vicinity thereof.
[0028]
In the thin film inspection apparatus of the present invention, the energy spectrum of backscattered ions is measured for a sample including a thin film having a known composition by the measuring device, and the virtual thin film having the known composition is determined by simulation by the control device. A spectrum of the difference between the energy spectrum and the energy spectrum measured for the sample is determined, and information about the thin film and the structure in the vicinity thereof is generated based on the spectrum of the difference.
[0029]
In the thin film inspection apparatus of the present invention, the control device may detect a different layer adjacent to the thin film and having a composition different from that of the thin film based on the difference spectrum. In this case, the control device may further detect the thickness of the different layer and the position of the different layer in the thickness direction of the thin film based on the difference spectrum.
[0030]
In the thin film inspection apparatus of the present invention, the measuring device includes a storage unit for storing a sample, an ion accelerator for emitting ions having an energy in the range of 250 to 500 keV, and ions emitted from the ion accelerator in the storage unit. An ion irradiation system for irradiating a stored sample, a magnetic field type energy analyzer for dispersing ions scattered by the sample according to energy, and a one-dimensional position detector for detecting ions dispersed by the energy analyzer You may have.
[0031]
Moreover, the thin film inspection apparatus of the present invention may further include an automatic transfer device that carries the sample into the storage unit and takes out the sample from the storage unit.
[0032]
The method of manufacturing a microdevice of the present invention includes a step of manufacturing a microdevice including a thin film having a known composition, and a step of manufacturing a microdevice. A process of inspecting, and the process of inspecting
A procedure for measuring the energy spectrum of backscattered ions by Rutherford backscattering spectroscopy under a predetermined condition for a sample including a thin film formed under the same conditions as the intermediate product,
Assuming a virtual thin film of known composition, the energy spectrum of backscattered ions obtained by Rutherford backscattering spectroscopy under the same conditions as the measurement for the sample is determined by simulation for this virtual thin film Procedure and
Obtaining a spectrum of the difference between the energy spectrum determined by simulation and the measured energy spectrum;
And a procedure for analyzing the structure of the thin film and the vicinity thereof based on the spectrum of the difference.
[0033]
In the method for manufacturing a microdevice of the present invention, the thin film in an intermediate product including the thin film and the structure in the vicinity thereof are inspected during the process of manufacturing the micro device. In this inspection process, a spectrum of a difference between an energy spectrum determined by simulation for a virtual thin film having a known composition and an energy spectrum measured for a sample including a thin film formed under the same conditions as the intermediate product is obtained. The thin film and the structure in the vicinity thereof are analyzed based on the difference spectrum.
[0034]
In the method for manufacturing a microdevice of the present invention, the analyzing procedure may detect a different layer adjacent to the thin film and having a composition different from that of the thin film, based on the difference spectrum. In this case, the analyzing procedure may further detect the thickness of the different layer and the position of the different layer in the thickness direction of the thin film based on the difference spectrum.
[0035]
In the method of manufacturing a microdevice of the present invention, the energy spectrum of the sample is measured by irradiating the sample with ions having an energy in the range of 250 to 500 keV, and using the ions scattered back by the sample as magnetic field type. The energy ions may be dispersed according to the energy, and the dispersed ions may be detected by a one-dimensional position detector.
[0036]
In the method of manufacturing a microdevice of the present invention, the step of inspecting further includes a first thin film having a known composition and a first composition having a first composition before the procedure for measuring the energy spectrum of the sample. There may be provided a procedure for producing a sample including the second thin film formed directly on the thin film or via a different layer.
[0037]
In the method for manufacturing a microdevice of the present invention, the microdevice may be a thin film magnetic head. In this case, the thin film magnetic head includes a magnetoresistive effect element and a lead layer connected to the magnetoresistive effect element, and the thin film having a known composition may be a film adjacent to the magnetoresistive effect element.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, the configuration of a thin film inspection apparatus according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is an explanatory diagram showing the overall configuration of a thin film inspection apparatus according to the present embodiment.
[0039]
The thin film inspection apparatus according to the present embodiment is an apparatus for inspecting a thin film and a structure in the vicinity thereof in a sample including a thin film having a known composition. This thin film inspection apparatus includes a measuring apparatus 101 that measures the energy spectrum of backscattered ions of a sample by Rutherford backscattering spectroscopy, an automatic conveyance apparatus 102 connected to the measurement apparatus 101, a measurement apparatus 101, and an automatic conveyance apparatus. And a control device 103 for controlling 102.
[0040]
The measurement apparatus 101 stores an analysis chamber 112 that stores a sample 111, an ion accelerator 113 that emits ions having energy in a medium energy region of 250 to 500 keV, and ions that are emitted from the ion accelerator 113 are stored in the analysis chamber 112. And an ion irradiation system for irradiating the formed sample 111. In the analysis chamber 112, a 5-axis gonio stage for arbitrarily setting the position of the sample 111 is provided. The analysis chamber 112 corresponds to the storage unit in the present invention. The ion irradiation system includes an objective slit 114, an E × B type (orthogonal electromagnetic field type) filter 115, and a quadrupole magnet 116 arranged in this order from the ion accelerator 113 side between the ion accelerator 113 and the analysis chamber 112. is doing. The objective slit 114 narrows the ion beam emitted from the ion accelerator 113. The E × B type filter 115 selectively passes an ion beam having a predetermined velocity among the ion beams that have passed through the objective slit 114. The quadrupole magnet 116 converges the ion beam that has passed through the E × B filter 115.
[0041]
The measuring apparatus 101 further includes a slit 117 for narrowing the ion beam backscattered by the sample 111, a magnetic field type energy analyzer 118 for dispersing the ion beam that has passed through the slit 117 according to energy, and the energy analysis. And a one-dimensional position detector 119 for detecting the ion beam dispersed by the device 118. For the one-dimensional position detector 119, for example, a microchannel plate is used.
[0042]
The automatic transfer apparatus 102 includes a load lock chamber 121 and a robot chamber 122 provided between the load lock chamber 121 and the analysis chamber 112. A wafer cassette 123 capable of storing a plurality of samples 111 is provided in the load lock chamber 121. In the load lock chamber 121, the sample 111 is taken in and out of the wafer cassette 123 without opening the analysis chamber 112 to the atmosphere. Two transfer robot arms 124 are provided in the robot chamber 122. Each arm 124 can perform a vertical movement and a rotational movement at the same time, and can advance and retreat independently. The arm 124 takes out the sample 111 from the wafer cassette 123, loads the sample 111 into the analysis chamber 112, and arranges it on the 5-axis goniometer stage. The arm 124 takes out the sample 111 from the analysis chamber 112 and stores it in the wafer cassette 123.
[0043]
Here, operations of the measuring apparatus 101 and the automatic conveyance apparatus 102 will be described. The sample 111 is first stored in the wafer cassette 123 in the load lock chamber 121. The sample 111 is taken out from the wafer cassette 123 by the transfer robot arm 124 and placed on the 5-axis gonio stage in the analysis chamber 112. After the position of the sample 111 is adjusted by the 5-axis goniostage, the energy spectrum of backscattered ions is measured on the sample 111 by Rutherford backscattering spectroscopy as follows. First, the accelerator 113 emits an ion beam having an energy in the range of 250 to 500 keV, for example, a He ion beam. A part of the ion beam passes through the ion irradiation system and is irradiated onto the sample 111. A part of the ion beam back-scattered by the sample 111 passes through the slit 117, is dispersed according to the energy by the energy analyzer 118, and enters the one-dimensional position detector 119. The one-dimensional position detector 119 detects the yield of backscattered ions for each energy. In this way, the relationship between the energy and yield of backscattered ions, that is, the energy spectrum is measured.
[0044]
While the measurement of the sample 111 is being performed, the sample 111 to be measured next is kept in the robot chamber 122 by one transfer robot arm 124. When the measurement of the sample 111 is completed, the sample 111 is taken out from the analysis chamber 112 by the other transfer robot arm 124, and immediately thereafter, the sample 111 to be measured next is analyzed by the one transfer robot arm 124. Carry in. Thereby, the time required for the measurement of the sample 111 can be shortened.
[0045]
The operations of the measurement apparatus 101 and the automatic conveyance apparatus 102 are controlled by the control apparatus 103. In addition, the control device 103 inputs an output signal of the one-dimensional position detector 119 and performs the following processing.
[0046]
The control device 103 inputs information on the energy spectrum measured by the measuring device 101 under a predetermined condition for the sample 111 including a thin film having a known composition. Further, the control device 103 assumes a virtual thin film having a known composition, and for this virtual thin film, backscattered ions obtained by Rutherford backscattering spectroscopy under the same conditions as those for measurement of the sample 111 Is determined by simulation. Further, the control device 103 obtains a spectrum of the difference between the energy spectrum determined by the simulation and the measured energy spectrum, and generates information on the thin film in the sample 111 and the structure in the vicinity thereof based on the difference spectrum. .
[0047]
FIG. 2 is a block diagram illustrating an example of the configuration of the control device 103. The control device 103 in this example includes a main control unit 131, a storage device 132 connected to the main control unit 131, an input / output control unit 133 connected to the main control unit 131, and the input / output control unit 133. An input device 134, a display device 135, and an output device 136 are provided. The main control unit 131 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The storage device 132 may be of any form as long as it can store information. For example, the storage device 132 is a hard disk device, an optical disk device, a floppy (registered trademark) disk device, or the like. The storage device 132 records information on the recording medium 137 and reproduces information from the recording medium 137. The recording medium 137 may be in any form as long as it can store information, and is, for example, a hard disk, an optical disk, a floppy (registered trademark) disk, or the like.
[0048]
The CPU in the main control unit 131 functions as the control device 103 by executing a program recorded in the recording medium 137 or the ROM in the main control unit 131 using the RAM in the main control unit 131 as a work area. It comes to show.
[0049]
Next, the thin film inspection method according to the present embodiment will be described with reference to the flowchart of FIG. The thin film inspection method according to the present embodiment is a method for inspecting a thin film in a sample 111 including a thin film having a known composition and a structure in the vicinity thereof. In this thin film inspection method, first, the energy spectrum of backscattered ions is measured by Rutherford backscattering spectrometry on the sample 111 using the measuring apparatus 101 under a predetermined condition (step S101).
[0050]
Next, in the control device 103, assuming a virtual thin film having a known composition, back scattering obtained by Rutherford backscattering spectroscopy under the same conditions as those for measurement of the sample 111 for this virtual thin film. The energy spectrum of ions is determined by simulation (step S102).
[0051]
Next, in the control device 103, a difference spectrum (hereinafter referred to as a difference spectrum) between an energy spectrum determined by simulation (hereinafter referred to as a simulation spectrum) and a measured energy spectrum (hereinafter referred to as a measurement spectrum). (Step S103).
[0052]
Next, the control device 103 analyzes the thin film and the structure in the vicinity thereof based on the difference spectrum (step S104), and the inspection is terminated. In step S104, the control device 103 detects a different layer adjacent to the thin film and having a composition different from that of the thin film, based on the difference spectrum. Further, the control device 103 detects the thickness of the different layer and the position of the different layer in the thickness direction of the thin film based on the difference spectrum.
[0053]
Note that the order of step S101 and step S102 may be reversed from the above description. Further, in the present embodiment, before step S101 for measuring the energy spectrum of the sample 111, the first thin film having a known composition and the known composition having a direct composition or a different layer on the first thin film. A step of producing a sample including the second thin film formed via the step may be provided.
[0054]
Hereinafter, Ta layer is formed on the surface of the Ta layer as a different layer. ₂ O ₅ A sample in which a layer is present or a different layer between two Ta layers ₂ O ₅ A method for obtaining the thicknesses of the Ta layer and the different layer will be described with reference to a sample having a layer.
[0055]
In the energy spectrum of backscattered ions obtained by Rutherford backscattering spectroscopy, the energy corresponds to the position (depth) from the surface and the yield corresponds to the amount of a given element. In addition, it represents that it is near the surface, so that energy is large. The spectrum width corresponds to the thickness of the layer containing the predetermined element. Therefore, the Ta distribution can be known from the measurement spectrum of the sample. Further, from the spectrum of the difference between the simulation spectrum and the measurement spectrum of the virtual thin film consisting of a single layer of Ta, Ta ₂ O ₅ The thickness of the layer and the position from the surface of the sample can be detected. When the peak portion of the difference spectrum exists at a position in contact with the end portion on the high energy side in the simulation spectrum, it means that a different layer exists on the surface of the Ta layer. Further, when the peak portion of the difference spectrum exists at an intermediate position between both ends in the simulation spectrum, it means that a different layer exists between the two Ta layers.
[0056]
Hereinafter, a method for obtaining the thicknesses of the Ta layer and the different layer will be described in detail. In the following description, the simulation refers to a simulation for calculating an energy spectrum of backscattered ions obtained by Rutherford backscattering spectroscopy for a virtual thin film. There are the following first and second methods for obtaining the thickness of the different layer.
[0057]
In the first method for determining the thickness of the different layer, first, the simulation is performed by setting the thickness of the virtual Ta film to be larger than the thickness of the different layer to be measured, and a reference energy spectrum (hereinafter referred to as the reference layer). Create a spectrum.)
[0058]
Next, the thickness of the virtual Ta film is set to about five different values such as 1 nm, 2 nm, and 3 nm, for example, and simulation is performed for each virtual Ta film of each thickness to create an energy spectrum. Next, for each energy spectrum, the integrated intensity (yield integrated value) of the energy spectrum is obtained. The relationship between the thickness of the virtual Ta film and the integrated intensity is expressed by a linear expression passing through the origin. This linear expression is used as a calibration curve for the Ta film.
[0059]
Next, a measurement spectrum is obtained for the sample, and a difference spectrum between the reference spectrum and the measurement spectrum is obtained. Next, the integrated intensity of the peak portion in the spectrum of the difference is obtained. When there are a plurality of peak portions, the integrated intensity is obtained for each peak.
[0060]
Next, the thickness is obtained from the integrated intensity of the peak portion in the difference spectrum, using the previously obtained Ta film calibration curve. This thickness represents the thickness of a layer made of a material different from pure Ta, that is, a different layer. In this way, the thickness of the different layer is obtained.
[0061]
In this first method, the different layer is Ta ₂ O ₅ This applies not only to the case of a layer, but also to a case where the different layer is any layer such as a case where the different layer is made of an unknown substance, a multilayer film, or a composition that differs depending on the position in the depth direction. be able to. In the first method, the absolute thickness of the different layer can be measured regardless of parameters such as the composition and density of the different layer.
[0062]
The first method can also be applied to the case where a different layer existing on the surface or inside of a thin film having a known composition other than Ta is detected by replacing Ta in the above description with another substance. . For example, when measuring the thickness of a diamond-like carbon (hereinafter referred to as DLC) film existing between two Si layers, a reference spectrum for the virtual Si film, a calibration curve for the Si film, and a sample The thickness of the DLC film can be obtained from the measured spectrum of and the spectrum of the difference between the reference spectrum and the measured spectrum.
[0063]
The second method for determining the thickness of the different layer is a method applicable when the composition of the different layer is known. Here, between two Ta layers, Ta ₂ O ₅ A case where a layer exists will be described as an example. In the second method, first, a simulation is performed by setting the thickness of the virtual Ta film to be larger than the thickness of the different layer to be measured, and a reference spectrum is created.
[0064]
Next, Ta layer, Ta ₂ O ₅ A hypothetical thin film having a structure in which a layer and a Ta layer are laminated in this order is assumed. And Ta in this virtual thin film ₂ O ₅ The thickness of the layer is set to about five different values, and simulation is performed for each value to create a simulation spectrum.
[0065]
Next, the spectrum of the difference between the reference spectrum and the simulation spectrum is obtained for each simulation spectrum. Next, the integrated intensity of the peak portion in the spectrum of the difference is obtained.
[0066]
Next, using the obtained integrated intensity, Ta ₂ O ₅ Create a calibration curve for the strata. This calibration curve is Ta ₂ O ₅ Represents the relationship between layer thickness and integrated intensity.
[0067]
Next, a measurement spectrum is obtained for the sample, and a difference spectrum between the reference spectrum and the measurement spectrum is obtained. Next, the integrated intensity of the peak portion in the spectrum of the difference is obtained.
[0068]
Next, Ta that I had been looking for earlier ₂ O ₅ From the integrated intensity of the peak part in the difference spectrum, Ta ₂ O ₅ Determine the thickness of the layer. In this way, Ta is a different layer. ₂ O ₅ The layer thickness is required.
[0069]
However, in the second method, the density of the substance existing between the two Ta layers is different from the density obtained from the stoichiometric composition of the expected substance, or exists between the two Ta layers. An error occurs when the composition of the material to be changed differs depending on the position in the depth direction.
[0070]
The second method is to use Ta existing on the surface of the Ta layer. ₂ O ₅ The present invention can also be applied to the case of determining the layer thickness. The second method can also be applied to a case where a different layer exists on the surface or inside of a thin film having a known composition other than Ta and the composition of the different layer is known.
[0071]
Next, a method for determining the thickness of the Ta layer in the sample will be described. First, the total thickness of the Ta layer and the different layer in the sample is determined as follows. That is, the simulation spectrum is determined so that the positions of both ends of the measurement spectrum for the sample coincide with the positions of both ends of the simulation spectrum for the virtual Ta film. The total thickness of the Ta layer and the different layer in the sample is obtained as the thickness of the virtual Ta film corresponding to the simulation spectrum thus determined.
[0072]
In the case of a sample having a different layer on the surface of the Ta layer, the thickness of the Ta layer is obtained by subtracting the thickness of the different layer obtained by the above-described method from the total thickness of the Ta layer and the different layer. Find the right.
[0073]
In the case of a sample in which a different layer exists between two Ta layers, two thicknesses can be obtained by subtracting the thickness of the different layer obtained by the above-described method from the total thickness of the Ta layer and the different layer. The total thickness of the Ta layer is obtained.
[0074]
Next, a method for obtaining the thickness of each Ta layer in the case of a sample in which a different layer exists between two Ta layers will be described. In this case, a minimum portion is generated at an intermediate position between both ends in the measurement spectrum of the sample. The position of the minimum portion corresponds to the position of the different layer. Therefore, a simulation spectrum is determined for a virtual Ta film having a shape that matches the shape of the measurement spectrum from the minimum portion to the end portion on the high energy side. Of the two Ta layers, the thickness of the Ta layer close to the surface of the sample is obtained as the thickness of the virtual Ta film corresponding to the simulation spectrum thus determined. Of the two Ta layers, the thickness of the Ta layer far from the surface of the sample can be obtained by subtracting the thickness of the Ta layer close to the surface of the sample from the total thickness of the two Ta layers obtained previously.
[0075]
Note that the above method can be applied to the case of detecting the thickness of a layer having a known composition other than Ta by replacing Ta in the above description with another substance.
[0076]
Hereinafter, first to fourth examples of the thin film inspection method according to the present embodiment will be described.
[0077]
[First embodiment]
In the first example, first and second samples were prepared. The first sample was produced as follows. That is, Ta was sputtered on the substrate to form a first Ta film having a thickness of 5 nm. Next, the laminated body thus obtained is exposed to the atmosphere, and a Ta oxide layer having a thickness of about 3 nm on the surface of the laminated body, that is, Ta ₂ O ₅ A layer was formed. Next, the laminated body was etched by 4.2 nm from the surface by ion milling. Next, Ta was sputtered on the surface of the laminate to form a second Ta film having a thickness of 10 nm. The first Ta film corresponds to the first thin film in the present invention, and the second Ta film corresponds to the second thin film in the present invention.
[0078]
The second sample was produced as follows. That is, Ta was sputtered on the substrate to form a first Ta film having a thickness of 5 nm. Next, the laminated body thus obtained is exposed to the atmosphere, and a Ta oxide layer having a thickness of about 3 nm on the surface of the laminated body, that is, Ta ₂ O ₅ A layer was formed. Next, the laminated body was etched by 2.6 nm from the surface by ion milling. Next, Ta was sputtered on the surface of the laminate to form a second Ta film having a thickness of 10 nm. The first Ta film corresponds to the first thin film in the present invention, and the second Ta film corresponds to the second thin film in the present invention.
[0079]
Next, the energy spectrum of backscattered ions was measured for each of the first and second samples by Rutherford backscattering spectroscopy using the measuring apparatus 101.
[0080]
On the other hand, in the control device 103, assuming the first and second virtual thin films made of a single layer of Ta corresponding to the first and second samples, respectively, the first and second virtual thin films are respectively described as the first and second virtual thin films. And the energy spectrum of backscattered ions obtained by Rutherford backscattering spectroscopy under the same conditions as in the measurement for the second sample was determined by simulation.
[0081]
Next, in the control apparatus 103, the spectrum of the difference between the simulation spectrum for the first virtual thin film and the measurement spectrum for the first sample was obtained. Similarly, in the control apparatus 103, the spectrum of the difference between the simulation spectrum for the second virtual thin film and the measurement spectrum for the second sample was obtained.
[0082]
FIG. 4 shows a simulation spectrum for the first virtual thin film, a measurement spectrum for the first sample, and a difference spectrum based thereon. 4, reference numeral 141 indicates a simulation spectrum, reference numeral 142 indicates a measurement spectrum, and reference numeral 143 indicates a difference spectrum. Note that the simulation spectrum of the first virtual thin film is determined so that the positions of both ends of the measurement spectrum coincide with the positions of both ends of the simulation spectrum. Specifically, the width of the simulation spectrum is made equal to the width of the measurement spectrum, and the position of the simulation spectrum is adjusted so that the residual mean square between the simulation spectrum and the measurement spectrum of the first sample is minimized, The simulation spectrum was determined. In the example shown in FIG. 4, the thickness of the first virtual thin film corresponding to the simulation spectrum determined in this way was 16.18 nm. The difference spectrum shown in FIG. 4 has one peak that exists in the vicinity of 280 keV. As can be seen from the comparison with the simulation spectrum, this peak is the Ta present on the surface of the first sample. ₂ O ₅ Represents a layer.
[0083]
As a result of analyzing the structure of the first sample by the thin film inspection method according to the present embodiment, the first sample has a Ta layer having a thickness of 1.57 nm on a Ta layer having a thickness of 14.61 nm. ₂ O ₅ Information was obtained that the structure had a layer.
[0084]
FIG. 5 shows a simulation spectrum for the second virtual thin film, a measurement spectrum for the second sample, and a difference spectrum based thereon. In FIG. 5, reference numeral 151 represents a simulation spectrum, reference numeral 152 represents a measurement spectrum, and reference numeral 153 represents a difference spectrum. Note that the simulation spectrum of the second virtual thin film is determined so that the positions of both ends of the measurement spectrum coincide with the positions of both ends of the simulation spectrum. Specifically, the width of the simulation spectrum is made equal to the width of the measurement spectrum, and the position of the simulation spectrum is adjusted so that the residual mean square between the simulation spectrum and the measurement spectrum of the second sample is minimized, The simulation spectrum was determined. In the example shown in FIG. 5, the thickness of the second virtual thin film corresponding to the simulation spectrum thus determined was 17.98 nm. The difference spectrum shown in FIG. 5 has a first peak present near 265 keV and a second peak present near 280 keV. As can be seen from the comparison with the simulation spectrum, the first peak is a Ta layer existing between the Ta layer formed by the first Ta film and the Ta layer formed by the second Ta film. ₂ O ₅ Represents a layer. Further, the second peak is the Ta existing on the surface of the second sample. ₂ O ₅ Represents a layer.
[0085]
As a result of analyzing the structure of the second sample by the thin film inspection method according to the present embodiment, the second sample has a Ta layer with a thickness of 0.24 nm on a Ta layer with a thickness of 4.16 nm. ₂ O ₅ Layer, Ta layer with a thickness of 11.89 nm, Ta layer with a thickness of 1.69 nm ₂ O ₅ Information was obtained that the layers were structured in this order.
[0086]
In this embodiment, the thickness of the virtual thin film is determined so that the width of the measurement spectrum and the width of the simulation spectrum match. However, when only the thickness and position of the different layers are obtained, the thickness of the virtual thin film is determined. May be set larger than the total thickness of the film having the known composition and the different layers.
[0087]
[Second Embodiment]
In the second example, a sample was prepared as follows. That is, Cu was sputtered onto a substrate whose surface was planarized by chemical mechanical polishing (CMP) to form a first Cu film having a thickness of 5 nm. Next, the laminated body thus obtained was exposed to the atmosphere, and a Cu oxide layer, that is, a CuO layer was formed on the surface of the laminated body. Next, Cu was sputtered on the surface of the laminate to form a second Cu film having a thickness of 5 nm.
[0088]
Next, using the measuring apparatus 101, the energy spectrum of backscattered ions was measured for the sample by Rutherford backscattering spectroscopy. On the other hand, assuming a virtual thin film composed of a single layer of Cu in the control device 103, each of the virtual thin films is obtained by Rutherford backscattering spectroscopy under the same conditions as those for measurement of the sample. The energy spectrum of the scattered ions was determined by simulation. Next, in the control apparatus 103, the spectrum of the difference between the simulation spectrum for the virtual thin film and the measurement spectrum for the sample was obtained.
[0089]
FIG. 6 shows a simulation spectrum for the virtual thin film, a measurement spectrum for the sample, and a difference spectrum based on these. In FIG. 6, reference numeral 161 indicates a simulation spectrum, reference numeral 162 indicates a measurement spectrum, and reference numeral 163 indicates a difference spectrum. The difference spectrum shown in FIG. 6 has one peak. As can be seen from comparison with the simulation spectrum, this peak represents the CuO layer existing between the Cu layer formed by the first Cu film and the Cu layer formed by the second Cu film. In the present embodiment, the thickness and position of the CuO layer can be detected based on the difference spectrum as in the first embodiment.
[0090]
[Third embodiment]
In the third example, a sample was produced as follows. That is, NiFe was sputtered on a substrate whose surface was planarized by chemical mechanical polishing (CMP) to form a first NiFe film having a thickness of 5 nm. Next, the laminated body thus obtained was exposed to the atmosphere, and a NiFe oxide layer, that is, a NiFeO layer was formed on the surface of the laminated body. Next, NiFe was sputtered on the surface of the laminate to form a second NiFe film having a thickness of 5 nm.
[0091]
Next, using the measuring apparatus 101, the energy spectrum of backscattered ions was measured for the sample by Rutherford backscattering spectroscopy. On the other hand, assuming a virtual thin film composed of a single layer of NiFe in the control device 103, each of the virtual thin films is obtained by Rutherford backscattering spectroscopy under the same conditions as those for measurement of the sample. The energy spectrum of the scattered ions was determined by simulation. Next, in the control apparatus 103, the spectrum of the difference between the simulation spectrum for the virtual thin film and the measurement spectrum for the sample was obtained.
[0092]
FIG. 7 shows a simulation spectrum for the virtual thin film, a measurement spectrum for the sample, and a difference spectrum based on these. In FIG. 7, reference numeral 171 represents a simulation spectrum, reference numeral 172 represents a measurement spectrum, and reference numeral 173 represents a difference spectrum. The difference spectrum shown in FIG. 7 has one peak. This peak represents the NiFeO layer existing between the NiFe layer formed by the first NiFe film and the NiFe layer formed by the second NiFe film, as can be seen from comparison with the simulation spectrum. In the present embodiment, the thickness and position of the NiFeO layer can be detected based on the difference spectrum in the same manner as in the first embodiment.
[0093]
[Fourth embodiment]
In the fourth example, a sample was prepared as follows. That is, a DLC film was formed on a Si substrate or a Si underlayer by depositing DLC by a CVD (chemical vapor deposition) method, a cathodic arc method, an ion beam deposition method, or the like. Next, Si was sputtered on the surface of the laminate thus obtained to form a Si film having a thickness of 5 nm.
[0094]
Next, using the measuring apparatus 101, the energy spectrum of backscattered ions was measured for the sample by Rutherford backscattering spectroscopy. On the other hand, assuming a virtual thin film composed of a single layer of Si in the control device 103, each of the virtual thin films is obtained by Rutherford backscattering spectroscopy under the same conditions as those for measurement of the sample. The energy spectrum of the scattered ions was determined by simulation. Next, in the control apparatus 103, the spectrum of the difference between the simulation spectrum for the virtual thin film and the measurement spectrum for the sample was obtained.
[0095]
FIG. 8 shows a simulation spectrum for the virtual thin film, a measurement spectrum for the sample, and a difference spectrum based on these. In FIG. 8, reference numeral 181 indicates a simulation spectrum, reference numeral 182 indicates a measurement spectrum, and reference numeral 183 indicates a difference spectrum. The difference spectrum shown in FIG. 8 has one peak. This peak represents the DLC film existing between the Si substrate and the Si film, as can be seen from comparison with the simulation spectrum. In this embodiment, the thickness and position of the DLC film can be detected based on the difference spectrum in the same manner as in the first embodiment.
[0096]
As described above, in the thin film inspection method and apparatus according to the present embodiment, the spectrum of the difference between the energy spectrum determined by the simulation for the virtual thin film having a known composition and the energy spectrum measured for the sample 111 is obtained. Based on the difference spectrum, the thin film and the structure in the vicinity thereof are analyzed. Therefore, according to the present embodiment, a thin film having a known composition and the structure in the vicinity thereof can be inspected easily and accurately.
[0097]
In the present embodiment, the sample 111 is irradiated with ions having an energy in the range of 250 to 500 keV with the best backscattering efficiency, and the ions backscattered by the sample are converted into magnetic field type energy having excellent energy spectral characteristics. The analyzer 118 is dispersed according to the energy, and the dispersed ions are detected by the one-dimensional position detector 119. Thereby, according to the present embodiment, a high depth resolution of about 0.2 nm can be realized.
[0098]
Therefore, according to the present embodiment, for example, the thickness and position of different layers such as a thin oxide layer existing on the surface of the thin film and a thin oxide layer existing between two adjacent thin films are determined. Therefore, it is possible to detect easily and accurately.
[0099]
In the present embodiment, when a He ion beam is used as the ion beam, all elements having an atomic number of 3 (Li atomic number) or more can be measured.
[0100]
Further, according to the present embodiment, even when a diffusion layer or a non-uniform layer exists at the interface between two adjacent thin films, the structure in the vicinity of the diffusion layer or the non-uniform layer is analyzed. Can do.
[0101]
By the way, when inspecting an oxide layer formed on the surface of a thin film during a thin film forming process such as sputtering or etching, an oxide layer formed by natural oxidation is formed on the surface when the thin film is exposed to the atmosphere. In the case of a thin film, the following problems occur. That is, when a sample having the thin film formed on the uppermost layer is taken out of the processing chamber for inspection and exposed to the atmosphere, an oxide layer due to natural oxidation is formed on the surface of the thin film. As a result, it is impossible to determine whether the oxide layer present on the surface of the thin film is formed during the processing or after the processing.
[0102]
In such a case, as in this embodiment, before the energy spectrum is measured for the sample 111, the first thin film having a known composition and the first composition having a known composition may be directly or directly on the first thin film. A sample 111 including the second thin film formed through the oxide layer may be manufactured. If this sample 111 is inspected by the thin film inspection method according to the present embodiment, an oxide layer present between the first thin film and the second thin film and an oxide layer present on the surface of the second thin film are obtained. Can be determined. The oxide layer existing between the first thin film and the second thin film is an oxide layer formed on the surface of the first thin film during the thin film forming process. Therefore, according to the present embodiment, it is possible to inspect the oxide layer formed on the surface of the thin film during the thin film formation processing.
[0103]
In the present embodiment, since the automatic transfer device 102 is connected to the measuring device 101, the throughput of the inspection of the sample 111 can be improved. Therefore, according to the present embodiment, for example, in the middle of a manufacturing process of a microdevice including a thin film having a known composition, the thin film and the structure in the vicinity thereof are inspected without greatly reducing the throughput of manufacturing the microdevice. It becomes possible to do.
[0104]
Next, a manufacturing method of the thin film magnetic head according to the present embodiment will be described. The thin film magnetic head corresponds to the microdevice in the present invention. Here, a method of manufacturing a thin film magnetic head including a reproducing head using a spin valve type giant magnetoresistive element (hereinafter referred to as a GMR element) will be described.
[0105]
First, an outline of a method for manufacturing a thin film magnetic head will be described with reference to FIGS. 9 to 14, (a) shows a cross section perpendicular to the air bearing surface, and (b) shows a cross section of the magnetic pole portion parallel to the air bearing surface.
[0106]
In the method of manufacturing the thin film magnetic head in this example, first, as shown in FIG. ₂ O _Three On the substrate 1 made of a ceramic material such as TiC, alumina (Al ₂ O _Three The insulating layer 2 made of an insulating material such as 1) is formed to a thickness of 1 to 5 μm, for example. Next, a lower shield layer 3 for a reproducing head made of a magnetic material such as permalloy (NiFe) is formed on the insulating layer 2 by a sputtering method or a plating method to a thickness of about 3 μm, for example.
[0107]
Next, the lower shield gap film 4 made of an insulating material such as alumina is formed on the lower shield layer 3 by a sputtering method or the like to a thickness of 10 to 200 nm, for example. Next, a reproducing GMR element 5 and a bias magnetic field application layer (not shown) are formed on the lower shield gap film 4 to a thickness of, for example, several tens of nm. The bias magnetic field application layer is disposed adjacent to both sides of the GMR element 5. The bias magnetic field application layer applies a bias magnetic field to the GMR element 5 in the longitudinal direction.
[0108]
Next, a pair of lead layers 6 is formed on the bias magnetic field application layer. The lead layer 6 is disposed so as to partially overlap the GMR element 5.
[0109]
Next, an upper shield gap film 7 made of an insulating material such as alumina is formed on the lower shield gap film 4, the GMR element 5 and the lead layer 6 by a sputtering method or the like to a thickness of 10 to 200 nm, for example.
[0110]
Next, an upper shield layer / lower magnetic pole layer (hereinafter referred to as a lower magnetic pole layer) 8 made of a magnetic material and used for both the reproducing head and the recording head is formed on the upper shield gap film 7, for example, 3 to 3. It is formed to a thickness of 4 μm. The magnetic material used for the bottom pole layer 8 is a soft magnetic material such as NiFe, CoFe, CoFeNi, FeN or the like. The bottom pole layer 8 is formed by sputtering or plating.
[0111]
Instead of the lower magnetic pole layer 8, an upper shield layer, a separation layer made of a nonmagnetic material such as alumina formed on the upper shield layer by sputtering or the like, and formed on the separation layer A lower magnetic layer may be provided.
[0112]
Next, as shown in FIG. 10, a recording gap layer 9 made of an insulating material such as alumina is formed on the lower magnetic pole layer 8 by a sputtering method or the like to a thickness of 50 to 300 nm, for example. Next, in order to form a magnetic path, the recording gap layer 9 is partially etched at the center portion of a thin film coil to be described later to form a contact hole 9a.
[0113]
Next, a first layer portion 10 of a thin film coil made of, for example, copper (Cu) is formed on the recording gap layer 9 to a thickness of, for example, 2 to 3 μm. In FIG. 10A, reference numeral 10 a represents a connection portion that is connected to the second layer portion 15 of the thin film coil to be described later in the first layer portion 10. The first layer portion 10 is wound around the contact hole 9a.
[0114]
Next, as shown in FIG. 11, an insulating layer made of an organic insulating material having fluidity when heated, such as a photoresist, so as to cover the first layer portion 10 of the thin film coil and the recording gap layer 9 in the vicinity thereof. 11 is formed in a predetermined pattern. Next, heat treatment is performed at a predetermined temperature in order to flatten the surface of the insulating layer 11. By this heat treatment, the edge portions of the outer periphery and inner periphery of the insulating layer 11 become rounded slope shapes.
[0115]
Next, on the recording gap layer 9 and the insulating layer 11 in a region from the slope portion on the air bearing surface 20 side (left side in FIG. 11A) to the air bearing surface 20 side, which will be described later, of the insulating layer 11. The track width defining layer 12a of the upper magnetic pole layer 12 is formed of a magnetic material for a recording head. The top pole layer 12 is composed of the track width defining layer 12a, and a coupling portion layer 12b and a yoke portion layer 12c described later. The track width defining layer 12a is formed by, for example, a plating method.
[0116]
The track width defining layer 12 a is formed on the recording gap layer 9 and serves as a magnetic pole portion of the upper magnetic pole layer 12. ₁ And a connecting portion 12a formed on the slope portion of the insulating layer 11 on the air bearing surface 20 side and connected to the yoke portion layer 12c. ₂ And have. Tip 12a ₁ Is equal to the recording track width. That is, the tip 12a ₁ Defines the recording track width. Connection part 12a ₂ The width of the tip portion 12a ₁ It is larger than the width.
[0117]
When the track width defining layer 12a is formed, at the same time, the connection portion layer 12b made of a magnetic material is formed on the contact hole 9a, and the connection layer 13 made of a magnetic material is formed on the connection portion 10a. The coupling portion layer 12 b constitutes a portion of the upper magnetic pole layer 12 that is magnetically coupled to the lower magnetic pole layer 8.
[0118]
Next, at least a part of the magnetic gap portions of the recording gap layer 9 and the lower magnetic pole layer 8 on the recording gap layer 9 side is etched around the track width defining layer 12a using the track width defining layer 12a as a mask. For example, reactive ion etching is used for etching the recording gap layer 9, and ion milling is used for etching the bottom pole layer 8, for example. As shown in FIG. 11B, the magnetic pole portion of the upper magnetic pole layer 12 (the tip portion 12a of the track width defining layer 12a). ₁ ), A structure in which the side walls of at least a part of the magnetic pole portions of the recording gap layer 9 and the lower magnetic pole layer 8 are formed in a self-aligned manner is called a trim structure.
[0119]
Next, as shown in FIG. 12, an insulating layer 14 made of an inorganic insulating material such as alumina is formed to a thickness of 3 to 4 μm, for example. Next, the insulating layer 14 is polished and planarized by chemical mechanical polishing to reach the surfaces of the track width defining layer 12a, the coupling portion layer 12b, and the connection layer 13, for example.
[0120]
Next, as shown in FIG. 13, a second layer portion 15 of a thin film coil made of, for example, copper (Cu) is formed on the planarized insulating layer 14 to a thickness of, for example, 2 to 3 μm. In FIG. 13A, reference numeral 15 a represents a connection portion of the second layer portion 15 that is connected to the connection portion 10 a of the first layer portion 10 of the thin film coil via the connection layer 13. The second layer portion 15 is wound around the connection portion layer 12b.
[0121]
Next, an insulating layer 16 made of an organic insulating material having fluidity when heated, such as a photoresist, is formed in a predetermined pattern so as to cover the second layer portion 15 of the thin film coil and the insulating layer 14 therearound. Next, heat treatment is performed at a predetermined temperature in order to flatten the surface of the insulating layer 16. By this heat treatment, the edge portions of the outer periphery and the inner periphery of the insulating layer 16 have a rounded slope shape.
[0122]
Next, as shown in FIG. 14, the yoke portion of the top pole layer 12 is formed on the track width defining layer 12a, the insulating layers 14 and 16, and the coupling portion layer 12b with a magnetic material for a recording head such as permalloy. The yoke partial layer 12c to be formed is formed. The end of the yoke portion layer 12 c on the air bearing surface 20 side is disposed at a position away from the air bearing surface 20. The yoke portion layer 12c is connected to the lower magnetic pole layer 8 through the coupling portion layer 12b.
[0123]
Next, an overcoat layer 17 made of alumina, for example, is formed so as to cover the entire surface. Finally, the slider including the above layers is machined to form the air bearing surface 20 of the thin film magnetic head including the recording head and the reproducing head, thereby completing the thin film magnetic head.
[0124]
The thin film magnetic head manufactured as described above includes a medium facing surface (air bearing surface 20) facing the recording medium, a reproducing head, and a recording head (inductive electromagnetic transducer). The reproducing head is arranged so that a part of the air bearing surface 20 side faces the GMR element 5 with the GMR element 5 interposed therebetween, and a lower shield layer 3 and an upper shield layer (lower part) for shielding the GMR element 5 Pole layer 8).
[0125]
The recording head includes magnetic pole portions that are magnetically coupled to each other and face each other on the air bearing surface 20 side, and each of the lower magnetic pole layer 8 and the upper magnetic pole layer 12 including at least one layer, and the magnetic poles of the lower magnetic pole layer 8 And a recording gap layer 9 provided between the portion and the magnetic pole portion of the upper magnetic pole layer 12, and at least a portion thereof is disposed between the lower magnetic pole layer 8 and the upper magnetic pole layer 12 in an insulated state. Thin film coils 10 and 15. In the thin film magnetic head according to the present embodiment, as shown in FIG. 14A, the length from the air bearing surface 20 to the end of the insulating layer 11 on the air bearing surface 20 side is the throat height TH. Become. The throat height refers to the length (height) from the end on the air bearing surface side to the end on the opposite side of the portion where the two pole layers are opposed via the recording gap layer.
[0126]
Next, a first example and a second example of the manufacturing method of the reproducing head in the thin film magnetic head will be described in detail.
[0127]
First, a first example of a reproducing head manufacturing method will be described with reference to FIGS. 15 to 28, (a) shows a cross section parallel to the air bearing surface, and (b) shows a cross section perpendicular to the air bearing surface. 15 to 28, the substrate 1, the insulating layer 2, and the lower shield layer 3 are omitted.
[0128]
In the first example, as shown in FIG. 15, a spin valve film 31 to be the GMR element 5 and a protective film 32 made of Ta are sequentially formed on the lower shield gap film 4 by sputtering, for example.
[0129]
Next, as shown in FIG. 16, portions of the protective film 32 and the spin valve film 31 where the bias magnetic field application layer is disposed are selectively etched by, for example, ion milling.
[0130]
Next, as shown in FIG. 17, a bias magnetic field application layer 33 and a protective film 34 are sequentially formed on the lower shield gap film 4 so as to be adjacent to both sides of the spin valve film 31 by, for example, sputtering. . The protective film 34 may be, for example, a Ta film, a stacked film of a Ta film, a TiW film, and a Ta film, or a stacked film of a TiW film and a Ta film.
[0131]
Next, as shown in FIG. 18, a stopper film 35 made of Ta is formed so as to cover the entire top surface of the stacked body, for example, by sputtering.
[0132]
Next, as shown in FIG. 19, in order to determine the MR height of the GMR element 5 by, for example, ion milling, the stopper film 35, the protective film 32, and the spin valve film 31 are selectively etched. The MR height refers to the length (height) from the end on the air bearing surface side to the opposite end of the MR element (including the GMR element 5). The spin valve film 31 patterned by this etching becomes the GMR element 5.
[0133]
Next, as shown in FIG. 20, the insulating layer 36 made of alumina is formed on the portion of the upper surface of the lower shield gap film 4 where the GMR element 5 and the bias magnetic field application layer 33 are not disposed by, for example, sputtering. Form.
[0134]
Next, as shown in FIG. 21, a part on the upper surface side of the insulating layer 36 is etched so that the upper surface of the stacked body approaches a flat surface by, for example, reactive ion etching. At this time, a part of the upper surface side of the stopper film 35 is oxidized, and a Ta oxide layer (Ta ₂ O ₅ Layer) 37 is formed.
[0135]
Next, as shown in FIG. 22, a part on the upper surface side of the stacked body is etched so that the oxide layer 37 is removed by, for example, ion milling. At this time, if the etching depth is equal to or greater than the thickness of the original oxide layer 37, the oxide layer 37 is completely removed, but the etching depth is smaller than the thickness of the oxide layer 37, as shown in FIG. Thus, the oxide layer 37 remains. In this example, the thickness of the oxide layer 37 in the intermediate product obtained by performing the processing up to the processing shown in FIG. 22 on the wafer is measured using the thin film inspection method according to the present embodiment.
[0136]
In this example, the thickness of the oxide layer 37 is measured using a measurement sample including the stopper film 35 formed under the same conditions as the intermediate product. The measurement sample may be formed, for example, by performing only the processing after the formation of the stopper film 35 on the wafer at the same time as the processing for the product wafer, or the product region and the measurement region on the wafer. These may be formed by performing the same process on these simultaneously. In the case of the latter measurement sample, the thickness of the oxide layer 37 is measured using the measurement region.
[0137]
In this example, as shown in FIG. 23, a Ta film 38 having a thickness of, for example, 5 nm is formed on the stopper film 35 in the measurement sample by, for example, sputtering. At this point in time, it is not known whether or not the oxide layer 37 remains on the stopper film 35. If the oxide layer 37 remains, the Ta film 38 is formed on the oxide layer 37.
[0138]
Next, for the measurement sample on which the Ta film 38 is formed, the thickness of the oxide layer 37 is measured using the thin film inspection method according to the present embodiment. As a result, when it is found that the oxide layer 37 remains on the stopper film 35, in the intermediate product, as shown in FIG. 24, for example, by ion milling, a part on the upper surface side of the stacked body Etch. The etching depth at this time is made larger than the thickness of the oxide layer 37 obtained by measurement. Thereby, the oxide layer 37 is completely removed. Thereafter, the electrode layer 6 is formed on the intermediate product.
[0139]
On the other hand, if the thickness of the oxide layer 37 is measured and it is found that the oxide layer 37 does not remain on the stopper film 35, the etching process shown in FIG. 24 is performed on the intermediate product. Instead, the formation process of the electrode layer 6 is performed.
[0140]
In the formation process of the electrode layer 6, first, as shown in FIG. 25, the resist layer is patterned by, for example, photolithography to form a mask 39 on the stopper film 35 at a position above the GMR element 5.
[0141]
Next, as shown in FIG. 26, the stopper film 35 is selectively etched by ion milling using a mask 39, for example. At this time, the protective film 34 is also etched, and further, a part of the protective film 32 and a part of the bias magnetic field application layer 33 are also etched.
[0142]
Next, the side surfaces of the stopper film 35 and the upper surface of the protective film 32 are slightly etched by reverse sputtering (sputter etching). Even if an oxide layer is formed on the side surface of the stopper film 35 and the upper surface of the protective film 32, this oxide layer can be removed by this etching.
[0143]
Next, as shown in FIG. 27, a base film 41 made of Ta, for example, an electrode film 42 made of Au, for example, a protective film 43 made of Ta, for example, is sequentially formed on the entire upper surface of the stacked body by sputtering, for example. . Next, the mask 39 is removed. As a result, the remaining electrode film 42 becomes the electrode layer 6. Thus, the electrode layer 6 is formed by the lift-off method.
[0144]
After the formation of the electrode layer 6, as shown in FIG. 28, the upper shield gap film 7 is formed on the entire upper surface of the multilayer body by, for example, sputtering.
[0145]
In this example, if the oxide layer 37 remains on the stopper film 35 before the step shown in FIG. 26, that is, the step of etching the stopper film 35, the etching of the stopper film 35 and the protective film 32 is performed. The depth becomes insufficient, the resistance value between the electrode layer 6 and the GMR element 5 becomes larger than a desired value, and the characteristics of the reproducing head deteriorate. In contrast, in this example, when the thickness of the oxide layer 37 is measured using the thin film inspection method according to the present embodiment during the manufacturing process of the reproducing head, and the oxide layer 37 remains. A process for removing the oxide layer 37 is performed. Therefore, according to this example, it is possible to prevent the reproduction head characteristics from being deteriorated due to the oxide layer 37 remaining as described above.
[0146]
In this example, an oxide layer remains on the side surfaces of the stopper film 35 and the upper surface of the protective film 32 before the step shown in FIG. If so, the resistance value between the electrode layer 6 and the GMR element 5 becomes larger than a desired value, and the characteristics of the reproducing head deteriorate. Therefore, by using the thin film inspection method according to the present embodiment, the thickness of the oxide layer formed on the side surface of the stopper film 35 and the upper surface of the protective film 32 is measured, so that the oxide layer is surely removed. In addition, the side surfaces of the stopper film 35 and the upper surface of the protective film 32 may be etched.
[0147]
Next, a second example of the reproducing head manufacturing method will be described with reference to FIGS. 29 to 40, (a) shows a cross section parallel to the air bearing surface, and (b) shows a cross section perpendicular to the air bearing surface. 29 to 40, the substrate 1, the insulating layer 2, and the lower shield layer 3 are omitted.
[0148]
In the second example, as shown in FIG. 29, a spin valve film 31 to be the GMR element 5 and a protective film 32 are sequentially formed on the lower shield gap film 4 by sputtering, for example. In this example, the protective film 32 includes a Ta film 32a, a CoFe film 32b, and a Ta film 32c formed in this order from the spin valve film 31 side.
[0149]
Next, as shown in FIG. 30, a portion of the protective film 32 and the spin valve film 31 where the bias magnetic field application layer is disposed is selectively etched by, for example, ion milling.
[0150]
Next, as shown in FIG. 31, a bias magnetic field application layer 33 and a protective film 34 are sequentially formed on the lower shield gap film 4 so as to be adjacent to both sides of the spin valve film 31 by, for example, sputtering. . The protective film 34 may be, for example, a Ta film, a stacked film of a Ta film, a TiW film, and a Ta film, or a stacked film of a TiW film and a Ta film.
[0151]
Next, as shown in FIG. 32, a stopper film 35 made of Ta is formed so as to cover the entire top surface of the stacked body by, for example, sputtering.
[0152]
Next, as shown in FIG. 33, the stopper film 35, the protective film 32, and the spin valve film 31 are selectively etched in order to determine the MR height of the GMR element 5 by, for example, ion milling. The spin valve film 31 patterned by this etching becomes the GMR element 5.
[0153]
Next, as shown in FIG. 34, the insulating layer 36 made of alumina is formed on the portion of the upper surface of the lower shield gap film 4 where the GMR element 5 and the bias magnetic field application layer 33 are not disposed by, for example, sputtering. Form.
[0154]
Next, as shown in FIG. 35, a part of the upper surface side of the insulating layer 36 is etched so that the upper surface of the stacked body approaches a flat surface by, for example, reactive ion etching. At this time, a part of the upper surface side of the stopper film 35 is oxidized, and a Ta oxide layer (Ta ₂ O ₅ Layer) 37 is formed.
[0155]
In this example, the thickness of the oxide layer 37 is measured using a measurement sample including the stopper film 35 formed under the same conditions as the intermediate product. The measurement sample may be formed, for example, by performing only the processing after the formation of the stopper film 35 on the wafer at the same time as the processing for the product wafer, or the product region and the measurement region on the wafer. These may be formed by performing the same process on these simultaneously. In the case of the latter measurement sample, the thickness of the oxide layer 37 is measured using the measurement region.
[0156]
In this example, as shown in FIG. 36, a Ta film 38 having a thickness of, for example, 5 nm is formed on the oxide layer 37 in the measurement sample by, for example, sputtering.
[0157]
Next, for the measurement sample on which the Ta film 38 is formed, the thickness of the oxide layer 37 is measured using the thin film inspection method according to the present embodiment. Then, the formation process of the electrode layer 6 is performed with respect to the intermediate product for products.
[0158]
In the formation process of the electrode layer 6, first, as shown in FIG. 37, the stacked body is etched until the Ta film 32a is exposed, for example, by ion milling. In this etching, the etching stop position can be made constant by controlling the etching conditions, for example, the etching time, in accordance with the thickness of the oxide layer 37 obtained by the above-described measurement.
[0159]
The above etching is performed while detecting elements scattered during etching using an ion milling apparatus equipped with an apparatus for analyzing elements by secondary ion mass spectrometry (SIMS), for example, from the CoFe film 32b. Etching may be stopped when scattered Co is detected. In the case of performing such etching, it is not necessary to measure the thickness of the oxide layer 37 and control the etching conditions according to the result.
[0160]
Next, the upper surface of the Ta film 32a is slightly etched by reverse sputtering (sputter etching). Even if an oxide layer is formed on the upper surface of the Ta film 32a, this oxide layer can be removed by this etching.
[0161]
Next, as shown in FIG. 38, a base film 51 made of Ta, for example, an electrode film 52 made of Au, for example, a protective film 53 made of Ta, for example, is sequentially formed on the entire upper surface of the stacked body by sputtering, for example. .
[0162]
Next, as shown in FIG. 39, the protective film 53 is patterned to form a mask 54 for patterning the electrode film 52.
[0163]
Next, as shown in FIG. 40, the electrode film 52 and the base film 51 are selectively etched by reactive ion etching using a gas such as argon or oxygen using a mask 54. As a result, the remaining electrode film 52 becomes the electrode layer 6.
[0164]
After the formation of the electrode layer 6, although not shown, the upper shield gap film 7 is formed on the entire upper surface of the multilayer body by, for example, sputtering.
[0165]
By the way, in this example, if the etching conditions in the step shown in FIG. 37, that is, the step of performing the etching to expose the Ta film 32a are made constant, the etching stop position is caused when the thickness of the oxide layer 37 varies. Will vary. As a result, the resistance value between the electrode layer 6 and the GMR element 5 varies, and the characteristics of the reproducing head vary. On the other hand, in this example, the thickness of the oxide layer 37 is measured using the thin film inspection method according to the present embodiment in the course of the manufacturing process of the reproducing head, and the etching conditions are adjusted according to the thickness. Is controlling. Therefore, according to this example, it is possible to prevent the characteristics of the reproducing head from varying depending on the thickness of the oxide layer 37.
[0166]
Hereinafter, a head gimbal assembly and a hard disk device to which the present embodiment is applied will be described. First, the slider 210 included in the head gimbal assembly will be described with reference to FIG. In the hard disk device, the slider 210 is arranged to face a hard disk that is a disk-shaped recording medium that is driven to rotate. The slider 210 includes a substrate 211 mainly composed of the substrate 1 and the overcoat layer 17 in FIG. The base body 211 has a substantially hexahedral shape. One of the six surfaces of the substrate 211 faces the hard disk. A rail portion 212 whose surface is an air bearing surface is formed on this one surface. A taper portion or a step portion is formed in the vicinity of the end portion of the rail portion 212 on the air inflow side (the upper right end portion in FIG. 41). When the hard disk rotates in the z direction in FIG. 41, an air flow that flows in from the taper portion or the step portion and passes between the hard disk and the slider 210 generates lift in the slider 210 below the y direction in FIG. The slider 210 floats from the surface of the hard disk by this lifting force. Note that the x direction in FIG. 41 is the track crossing direction of the hard disk. Near the end of the slider 210 on the air outflow side (lower left end in FIG. 41), a thin film magnetic head 100 to which the embodiments of the present invention are applied is formed.
[0167]
Next, the head gimbal assembly 220 will be described with reference to FIG. The head gimbal assembly 220 includes a slider 210 and a suspension 221 that elastically supports the slider 210. The suspension 221 is, for example, a leaf spring-shaped load beam 222 formed of stainless steel, a flexure 223 that is provided at one end of the load beam 222 and is joined to the slider 210 to give the slider 210 an appropriate degree of freedom. And a base plate 224 provided at the other end of the beam 222. The base plate 224 is attached to an arm 230 of an actuator for moving the slider 210 in the track crossing direction x of the hard disk 262. The actuator has an arm 230 and a voice coil motor that drives the arm 230. In the flexure 223, a part to which the slider 210 is attached is provided with a gimbal part for keeping the posture of the slider 210 constant.
[0168]
The head gimbal assembly 220 is attached to the arm 230 of the actuator. A structure in which the head gimbal assembly 220 is attached to one arm 230 is called a head arm assembly. Further, a head gimbal assembly 220 attached to each arm of a carriage having a plurality of arms is called a head stack assembly.
[0169]
FIG. 42 shows an example of the head arm assembly. In this head arm assembly, a head gimbal assembly 220 is attached to one end of the arm 230. A coil 231 that is a part of the voice coil motor is attached to the other end of the arm 230. A bearing portion 233 attached to a shaft 234 for rotatably supporting the arm 230 is provided at an intermediate portion of the arm 230.
[0170]
Next, an example of a head stack assembly and a hard disk device will be described with reference to FIGS. FIG. 43 is an explanatory diagram showing the main part of the hard disk device, and FIG. 44 is a plan view of the hard disk device. The head stack assembly 250 has a carriage 251 having a plurality of arms 252. A plurality of head gimbal assemblies 220 are attached to the plurality of arms 252 so as to be arranged in the vertical direction at intervals. A coil 253 that is a part of the voice coil motor is attached to the carriage 251 on the side opposite to the arm 252. The head stack assembly 250 is incorporated in a hard disk device. The hard disk device has a plurality of hard disks 262 attached to a spindle motor 261. For each hard disk 262, two sliders 210 are arranged so as to face each other with the hard disk 262 interposed therebetween. Further, the voice coil motor has permanent magnets 263 arranged at positions facing each other with the coil 253 of the head stack assembly 250 interposed therebetween.
[0171]
The head stack assembly 250 and the actuator excluding the slider 210 support the slider 210 and position it relative to the hard disk 262.
[0172]
In this hard disk device, the slider 210 is moved relative to the hard disk 262 by moving the slider 210 in the track crossing direction of the hard disk 262 by the actuator. The thin film magnetic head included in the slider 210 records information on the hard disk 262 by the recording head, and reproduces information recorded on the hard disk 262 by the reproducing head.
[0173]
In addition, this invention is not limited to the said embodiment, A various change is possible. For example, the present invention is not limited to the case of inspecting an oxide layer, but can be applied to the general case of inspecting a heterogeneous layer adjacent to a thin film having a known composition. The present invention can also be applied to a method of manufacturing a microdevice other than a thin film magnetic head, such as a semiconductor device, a sensor or an actuator using a thin film.
[0174]
【The invention's effect】
As described above, in the thin film inspection method according to any one of claims 1 to 5 or the thin film inspection apparatus according to any one of claims 6 to 10, energy determined by simulation for a virtual thin film having a known composition. The spectrum of the difference between the spectrum and the energy spectrum measured for the sample is obtained, and the thin film and the structure in the vicinity thereof are analyzed based on the spectrum of the difference. Therefore, according to the present invention, it is possible to easily and accurately inspect a thin film having a known composition and a structure in the vicinity thereof.
[0175]
Further, in the thin film inspection method according to claim 4 or the thin film inspection apparatus according to claim 9, the sample is irradiated with ions having an energy in the range of 250 to 500 keV, and the ions scattered back by the sample are subjected to magnetic field type energy. The analyzer is dispersed according to energy, and the dispersed ions are detected by a one-dimensional position detector. According to the present invention, high depth resolution can be realized. As a result, the thickness and position of the thin different layer existing on the surface of the thin film and the thin different layer existing between two adjacent thin films can be simplified. In addition, there is an effect that detection can be performed with high accuracy.
[0176]
Further, in the thin film inspection method according to claim 5, before the energy spectrum of the sample is measured, the first thin film having a known composition and the known composition having a first composition or a different layer directly on the first thin film. A sample including the second thin film formed via the substrate is prepared. According to the present invention, it is possible to discriminate between the different layer existing between the first thin film and the second thin film and the different layer existing on the surface of the second thin film. There is an effect that it becomes possible to inspect the oxide layer formed on the surface of the first thin film during the thin film forming process.
[0177]
According to the thin film inspection apparatus of the tenth aspect, since the automatic transfer apparatus is provided, there is an effect that the throughput of the inspection of the sample can be improved.
[0178]
The method of manufacturing a microdevice according to any one of claims 11 to 17 includes a step of manufacturing a microdevice including a thin film having a known composition and an intermediate including a thin film during the process of manufacturing the microdevice. A step of inspecting a thin film in the product and a structure in the vicinity thereof, and the step of inspecting was formed under the same conditions as the intermediate product and the energy spectrum determined by simulation for a virtual thin film having a known composition A difference spectrum from the energy spectrum measured for the sample including the thin film is obtained, and the thin film and the structure in the vicinity thereof are analyzed based on the difference spectrum. Therefore, according to the present invention, it is possible to easily and accurately inspect a thin film having a known composition and a structure in the vicinity thereof during the manufacturing process of a microdevice including a thin film having a known composition. Play.
[0179]
In the method of manufacturing a microdevice according to claim 14, ions having an energy within a range of 250 to 500 keV are irradiated on the sample, and ions scattered by the sample are subjected to energy by a magnetic field type energy analyzer. The dispersed ions are dispersed and detected by a one-dimensional position detector. According to the present invention, high depth resolution can be realized. As a result, the thickness and position of the thin different layer existing on the surface of the thin film and the thin different layer existing between two adjacent thin films can be simplified. In addition, there is an effect that detection can be performed with high accuracy.
[0180]
Further, in the method of manufacturing a microdevice according to claim 15, before measuring the energy spectrum of the sample, the first thin film having a known composition and the first composition having a known composition and directly on the first thin film or A sample including the second thin film formed through the different layer is prepared. According to the present invention, it is possible to discriminate between the different layer existing between the first thin film and the second thin film and the different layer existing on the surface of the second thin film. There is an effect that the oxide layer formed on the surface of the thin film can be inspected during the thin film forming process.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an overall configuration of a thin film inspection apparatus according to an embodiment of the present invention.
FIG. 2 is a block diagram illustrating an example of a configuration of a control device in FIG.
FIG. 3 is a flowchart for explaining a thin film inspection method according to an embodiment of the present invention.
FIG. 4 is a characteristic diagram showing a measurement result in the first example of the thin film inspection method according to the embodiment of the invention.
FIG. 5 is a characteristic diagram showing a measurement result in the first example of the thin film inspection method according to the embodiment of the invention.
FIG. 6 is a characteristic diagram showing a measurement result in a second example of the thin film inspection method according to the embodiment of the invention.
FIG. 7 is a characteristic diagram showing measurement results in the third example of the thin film inspection method according to one embodiment of the present invention.
FIG. 8 is a characteristic diagram showing measurement results in the fourth example of the thin film inspection method according to one embodiment of the present invention.
FIG. 9 is a cross-sectional view for explaining a step in the method of manufacturing a thin film magnetic head according to the embodiment of the invention.
10 is a cross-sectional view for explaining a process following the process depicted in FIG. 9. FIG.
11 is a cross-sectional view for explaining a step that follows the step shown in FIG. 10. FIG.
12 is a cross-sectional view for explaining a process following the process depicted in FIG. 11. FIG.
13 is a cross-sectional view for explaining a process following the process depicted in FIG. 12. FIG.
14 is a cross-sectional view for explaining a step that follows the step shown in FIG. 13. FIG.
FIG. 15 is a cross-sectional view for explaining a step in the first example of the reproducing head manufacturing method according to the embodiment of the invention.
16 is a cross-sectional view for explaining a process following the process depicted in FIG. 15. FIG.
FIG. 17 is a cross-sectional view for explaining a process following the process depicted in FIG. 16;
FIG. 18 is a cross sectional view for illustrating a step following the step shown in FIG.
FIG. 19 is a cross-sectional view for explaining a process following the process depicted in FIG. 18;
20 is a cross-sectional view for explaining a process following the process depicted in FIG. 19. FIG.
FIG. 21 is a cross-sectional view for explaining a process following the process depicted in FIG. 20;
22 is a cross-sectional view for explaining a step following the step shown in FIG. 21. FIG.
FIG. 23 is a cross-sectional view for explaining a process following the process depicted in FIG. 22;
24 is a cross-sectional view for explaining a step following the step shown in FIG. 23. FIG.
25 is a cross-sectional view for explaining a process following the process depicted in FIG. 24. FIG.
FIG. 26 is a cross-sectional view for illustrating a step that follows the step shown in FIG. 25.
FIG. 27 is a cross-sectional view for explaining a process following the process depicted in FIG. 26;
FIG. 28 is a cross sectional view for illustrating a step following the step shown in FIG. 27.
FIG. 29 is a cross-sectional view for explaining a step in the second example of the reproducing head manufacturing method according to an embodiment of the present invention.
30 is a cross-sectional view for explaining a process following the process depicted in FIG. 29; FIG.
FIG. 31 is a cross-sectional view for explaining a process following the process depicted in FIG. 30;
32 is a cross-sectional view for illustrating a process following the process depicted in FIG. 31. FIG.
FIG. 33 is a cross-sectional view for explaining a process following the process depicted in FIG. 32;
34 is a cross-sectional view for explaining a process following the process depicted in FIG. 23; FIG.
FIG. 35 is a cross sectional view for illustrating a step following the step shown in FIG. 34.
FIG. 36 is a cross sectional view for illustrating a step following the step shown in FIG. 35.
FIG. 37 is a cross sectional view for illustrating a step following the step shown in FIG. 36.
FIG. 38 is a cross sectional view for illustrating a step following the step shown in FIG. 37.
FIG. 39 is a cross sectional view for illustrating a step following the step shown in FIG. 38.
40 is a cross sectional view for illustrating a process following the process depicted in FIG. 39. FIG.
FIG. 41 is a perspective view showing a slider included in a head gimbal assembly to which an embodiment of the present invention is applied.
42 is a perspective view showing a head arm assembly including a head gimbal assembly to which an embodiment of the present invention is applied. FIG.
FIG. 43 is an explanatory diagram showing a main part of a hard disk device to which an embodiment of the present invention is applied.
FIG. 44 is a plan view of a hard disk drive to which an embodiment of the present invention is applied.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 101 ... Measuring apparatus, 102 ... Automatic conveyance apparatus, 103 ... Control apparatus, 111 ... Sample, 112 ... Analysis chamber, 113 ... Ion accelerator, 114 ... Objective slit, 115 ... ExB type filter, 116 ... Quadrupole magnet, DESCRIPTION OF SYMBOLS 117 ... Slit, 118 ... Energy analyzer, 119 ... One-dimensional position detector, 121 ... Load lock chamber, 122 ... Robot chamber, 123 ... Wafer cassette, 124 ... Robot arm.

Claims (17)

A thin film inspection method for inspecting the thin film in a sample including a thin film having a known composition and a structure of a heterogeneous layer adjacent to the thin film and having a different composition from the thin film,
A procedure for measuring the energy spectrum of backscattered ions by Rutherford backscattering spectroscopy under a predetermined condition for the sample;
Assuming a virtual thin film having the above-mentioned known composition, the energy spectrum of backscattered ions obtained by Rutherford backscattering spectroscopy under the same conditions as the measurement for the sample is simulated for this virtual thin film. The procedure determined by
Obtaining a spectrum of the difference between the energy spectrum determined by the simulation and the measured energy spectrum;
A thin film inspection method comprising: analyzing a structure of the thin film and the heterogeneous layer based on a position of a peak portion in the spectrum of the difference and an integrated intensity of the peak portion . 2. The thin film inspection method according to claim 1, wherein the analyzing step detects the heterogeneous layer based on a position of a peak portion and an integrated intensity of the peak portion in the difference spectrum. The analyzing step further detects the thickness of the different layer and the position of the different layer in the thickness direction of the thin film based on the position of the peak portion in the difference spectrum and the integrated intensity of the peak portion. The thin film inspection method according to claim 2.   The procedure for measuring the energy spectrum of the sample is to irradiate the sample with ions having an energy in the range of 250 to 500 keV, and to disperse the ions back-scattered by the sample according to the energy by a magnetic field type energy analyzer. The thin film inspection method according to any one of claims 1 to 3, wherein the dispersed ions are detected by a one-dimensional position detector.   Furthermore, prior to the procedure for measuring the energy spectrum of the sample, the first thin film having the known composition and the known composition having the known composition and directly on the first thin film or via the dissimilar layer The thin film inspection method according to claim 1, further comprising a procedure for producing a sample including the formed second thin film. A thin film inspection apparatus for inspecting the thin film in a sample including a thin film having a known composition and a structure of a heterogeneous layer adjacent to the thin film and having a different composition from the thin film,
A measuring device for measuring the energy spectrum of backscattered ions of the sample by Rutherford backscattering spectroscopy;
For the sample, information on the energy spectrum measured by the measuring device under a predetermined condition is input, and the virtual thin film having the known composition is assumed, and the virtual thin film is measured for the sample. The energy spectrum of backscattered ions obtained by Rutherford backscattering spectroscopy under the same conditions as in the simulation is determined by simulation, and the difference spectrum between the energy spectrum determined by the simulation and the measured energy spectrum is determined. A thin film inspection apparatus comprising: a control device that generates information on the structure of the thin film and the different layer based on the position of the peak portion in the spectrum of the difference and the integrated intensity of the peak portion . The thin film inspection apparatus according to claim 6, wherein the control device detects the heterogeneous layer based on a position of a peak portion in the spectrum of the difference and an integrated intensity of the peak portion . The controller further detects the thickness of the different layer and the position of the different layer in the thickness direction of the thin film based on the position of the peak portion in the spectrum of the difference and the integrated intensity of the peak portion. The thin film inspection apparatus according to claim 7.   The measurement apparatus includes a storage unit that stores the sample, an ion accelerator that emits ions having an energy in a range of 250 to 500 keV, and ions that are emitted from the ion accelerator are stored in the sample stored in the storage unit. An ion irradiation system for irradiation, a magnetic field type energy analyzer that disperses ions back-scattered by the sample according to energy, and a one-dimensional position detector that detects ions dispersed by the energy analyzer The thin film inspection apparatus according to claim 6, wherein the apparatus is a thin film inspection apparatus.   The thin film inspection apparatus according to claim 6, further comprising an automatic transfer device that carries the sample into the storage unit and takes out the sample from the storage unit. Manufacturing a microdevice including a thin film having a known composition;
In the middle of the process of manufacturing the microdevice, manufacturing the microdevice comprising the thin film in the intermediate product including the thin film, and the step of inspecting the structure of the heterogeneous layer adjacent to the thin film and having a different composition from the thin film A method,
The inspection step includes
A procedure for measuring the energy spectrum of backscattered ions by Rutherford backscattering spectroscopy under a predetermined condition for a sample including the thin film formed under the same conditions as the intermediate product,
Assuming a virtual thin film having the above-mentioned known composition, the energy spectrum of backscattered ions obtained by Rutherford backscattering spectroscopy under the same conditions as the measurement for the sample is simulated for this virtual thin film. The procedure determined by
Obtaining a spectrum of the difference between the energy spectrum determined by the simulation and the measured energy spectrum;
A method of manufacturing a microdevice, comprising: analyzing a structure of the thin film and the heterogeneous layer based on a position of a peak portion in the spectrum of the difference and an integrated intensity of the peak portion . 12. The method of manufacturing a microdevice according to claim 11, wherein the analyzing step detects the heterogeneous layer based on a position of a peak portion and an integrated intensity of the peak portion in the spectrum of the difference. The analyzing step further detects the thickness of the different layer and the position of the different layer in the thickness direction of the thin film based on the position of the peak portion in the spectrum of the difference and the integrated intensity of the peak portion. The method for manufacturing a microdevice according to claim 12.   The procedure for measuring the energy spectrum of the sample is to irradiate the sample with ions having an energy in the range of 250 to 500 keV, and to disperse the ions back-scattered by the sample according to the energy by a magnetic field type energy analyzer. 14. The method of manufacturing a micro device according to claim 11, wherein the dispersed ions are detected by a one-dimensional position detector.   The step of inspecting further comprises a first thin film of the known composition and a first composition of the known composition, directly or on the first thin film, prior to the procedure of measuring an energy spectrum for the sample. 15. The method of manufacturing a microdevice according to claim 11, further comprising a step of manufacturing a sample including the second thin film formed via the different layer.   16. The method of manufacturing a micro device according to claim 11, wherein the micro device is a thin film magnetic head.   The thin film magnetic head includes a magnetoresistive effect element and a lead layer connected to the magnetoresistive effect element, and the thin film having the known composition is a film adjacent to the magnetoresistive effect element. The method of manufacturing a microdevice according to claim 16.

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