JP2008304341A - Apparatus for measuring particle adhesion - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and method for measuring a particle adhesion, which can solve the problem that measuring the adhesion of a fine particle whose particle size is 5 μm or less can not be performed by conventional methods, and can measure the adhesion of the fine particle easily. <P>SOLUTION: The apparatus includes a means for measuring the adhesion of the particle on a substrate positioned inside a focused ion beam system. More specifically, in the focused ion beam system, the adhesion of the fine particle can be measured by a contact needle, a means for immobilizing the fine particle and a measurement of an amount of variation in a leaf spring moving along with the contact needle. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a particle adhesion measuring device for measuring particle adhesion.

  Conventionally, centrifugation, optical microscopy, and the like have been used as methods for measuring the adhesion of fine particles.

  For example, the centrifugation method is disclosed in Japanese Patent Application Laid-Open No. 2006-220472.

  Rotate the sample substrate with the particles attached, and calculate the adhesion force of the powder using the particle size, specific gravity of the particles when the particles are detached from the sample substrate, and the number of rotations of the rotor during separation from the sample substrate. Is disclosed.

  Optical microscopy is disclosed in Japanese Patent Application Laid-Open No. 2003-294608. Disclosure of measuring the adhesive force from the displacement of the contact needle when the particle moves away from the substrate while the contact needle is adhered to the particle on the substrate with an adhesive and the contact needle is moved under observation with an optical microscope Has been.

JP 2006-220472 A JP 2003-294608 A

  Since the apparatus for measuring the adhesion force of particles disclosed in Japanese Patent Application Laid-Open No. 2006-220472 uses centrifugal force, the centrifugal force applied to the particles becomes smaller as the particles become smaller. The following particle adhesion cannot be measured.

  Further, the apparatus for measuring the adhesion force of particles disclosed in Japanese Patent Application Laid-Open No. 2003-294608 is a method for measuring particles and contact needles to be measured while observing them with an optical microscope when bonding the particles and contact needles with an adhesive. Therefore, since it is difficult to observe fine particles having a diameter of about 10 μm or less, only particles having a diameter of about 10 μm or more can be measured. In addition, since the contact needle is adhered to the particle with an adhesive, it is difficult to perform without attaching the adhesive to the region other than the particle and the contact needle as the particle size decreases. In addition, individual differences occur in the state of adhesion.

  The present invention has been made in view of such conventional problems, and is a drawback of the above-described prior art, that is, measurement of the adhesion force of fine particles having a particle size of 5 μm or less that could not be measured so far. An object of the present invention is to provide a particle adhesion measuring apparatus and method that can solve the problem and easily measure the adhesion of fine particles.

  FIG. 1 shows a cross section of the particle adhesion measuring device of the present invention which is a basic conceptual diagram of the present invention. The outline of the present invention will be described with reference to FIG.

  In order to solve the above problems, the particle adhesion measuring apparatus of the present invention includes a sample stage 3 for fixing a substrate 2 to which particles 1 are adhered, a plate spring 4 that is fixed with one end fixed, and a tip of the plate spring. A contact needle 5 fixed to the contact needle, a means for fixing the particles to the tip of the contact needle, a drive means 6 for moving the contact element forward and backward to contact and separate, and a measurement means 7 for measuring the displacement of the leaf spring. A particle adhesion force measuring apparatus comprising:

  Secondary electrons generated by scanning the focused ion beam 9 irradiated from the focused ion beam device 8 are fixed to the tip of the contact needle and the state in which the contact is moved forward and backward is brought into contact and separated. It is possible to detect and observe with the charged particle detector 10.

  Here, the means for fixing the particles to the tip of the contact needle is performed by a deposition process by the deposition apparatus 11. Here, the material 12 to be deposited is not particularly limited as long as it can be deposited. This is shown in FIG. For the purpose of fixing only the tip of the contact needle and the particles, a material that can easily control the deposition region so as not to deposit in another region is desirable. A deposition material capable of controlling the deposition area with a diameter of about 10 nm is desirable. For example, deposition is performed with diamond-like carbon.

  Another means for fixing the particles to the tip of the leaf spring is a method performed by a manipulator. Charge is applied to the tip of the manipulator 13 shown in FIG. For example, when an electric charge is applied to positively charge the tip of the manipulator 14, the tip of the manipulator opens due to electrostatic repulsion. After the particles are sandwiched by the manipulator, the charge is removed to close the tip of the manipulator, and the particle can be fixed to the tip of the manipulator. Here, the tip of the manipulator is charged positively, but even if charged negatively, the manipulator tip can be opened and closed in the same manner, and the particles can be fixed to the tip of the manipulator.

  As described above, the force for pulling the particles fixed to the tip of the contact needle or the particle fixed to the tip of the manipulator is measured based on the displacement amount of the leaf spring to thereby determine the adhesion force between the substrate and the particles. Can be measured. Here, the pulling direction may be perpendicular or parallel to the substrate, and there is no particular limitation on the pulling direction.

  The change amount measuring means is measurement of displacement of a laser displacement meter that irradiates laser light or measurement of voltage displacement by a piezoelectric element, and can measure a force of pulling the particles by the change amount.

  In addition, the particle adhesion measuring apparatus of the present invention can measure the adhesion between the substrate and the substrate and between the particle and the particle, in addition to the adhesion between the particle and the substrate.

  In the particle adhesion measuring apparatus of the present invention, the particles on the substrate can be removed by fixing and pulling the particles on the contact needle by the deposition, or by pulling the particles with the manipulator.

  The present invention is also a device manufacturing method characterized by being manufactured by removing particles on a substrate using the particle adhesion measuring device of the present invention.

  Specifically, FIG. 1 shows a cross section of the particle adhesion measuring apparatus of the present invention which is a basic conceptual diagram of the present invention. The outline of the present invention will be described with reference to FIG. However, for removing the particles, the leaf spring 4 interlocked with the contact needle and the measuring means 7 for measuring the displacement of the leaf spring are means for measuring the adhesion force of the particles, and thus are not necessary for removing the particles. However, the leaf spring 4 interlocked with the contact needle and the measuring means 7 for measuring the displacement of the leaf spring are not particularly problematic.

  In order to solve the above problems, the particle adhesion measuring apparatus of the present invention includes a sample stage 3 for fixing a substrate 2 to which particles 1 are adhered, a contact needle 5 fixed to the tip of the leaf spring, and a tip of the contact needle. And a driving means 6 for advancing and retracting the contact to contact and separate the particles.

  Secondary electrons generated by scanning the focused ion beam 9 irradiated from the focused ion beam device 8 are fixed to the tip of the contact needle and the state in which the contact is moved forward and backward is brought into contact and separated. It is possible to detect and observe with the charged particle detector 10.

  Here, the means for fixing the particles to the tip of the contact needle is performed by a deposition process by the deposition apparatus 11. Here, the material 12 to be deposited is not particularly limited as long as it can be deposited. This is shown in FIG. For the purpose of fixing only the tip of the contact needle and the particles, a material that can easily control the deposition region so as not to deposit in another region is desirable. A deposition material capable of controlling the deposition area with a diameter of about 10 nm is desirable. For example, deposition is performed with diamond-like carbon.

  Another means for fixing the particles to the tip of the leaf spring is a method performed by a manipulator. Charge is applied to the tip of the manipulator 13 shown in FIG. For example, when an electric charge is applied to positively charge the tip of the manipulator 14, the tip of the manipulator opens due to electrostatic repulsion. After the particles are sandwiched by the manipulator, the charge is removed to close the tip of the manipulator, and the particle can be fixed to the tip of the manipulator. Here, the tip of the manipulator is charged positively, but even if charged negatively, the manipulator tip can be opened and closed in the same manner, and the particles can be fixed to the tip of the manipulator.

  As described above, the particles are removed from the substrate by pulling the particles fixed to the tip of the contact needle or the particles fixed to the tip of the manipulator. Here, the pulling direction may be perpendicular or parallel to the substrate, and there is no particular limitation on the pulling direction.

  In addition to the removal of particles from the substrate, the apparatus of the present invention can also remove substrates and particles.

  According to the present invention, it is possible to solve the problem of easily measuring the adhesion force of fine particles on a substrate. Knowing the exact value of the adhesive force will guide the study of cleaning methods necessary to remove particles on the substrate, and will manage the cleanliness of electronic devices such as magnetic disk drives that require increasingly high cleanliness. It becomes easy and can be manufactured at a high yield.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  The adhesion force of polystyrene particles having a diameter of 0.2 μm to 19 μm adhered on the Si substrate was measured using the particle adhesion force measuring device of the present invention.

  The particle adhesion measuring apparatus used in this example includes a sample stage for fixing a Si substrate to which polystyrene particles are attached, a plate spring that is fixed with one end fixed, and a contact needle that is fixed to the tip of the plate spring. Particles comprising: means for fixing the particles to the tip of the contact needle; and drive means for moving the contact element back and forth to contact and separate; and measurement means for measuring the displacement of the leaf spring It is an adhesive force measuring device.

  Further, the particles were fixed to the tip of the contact needle. Then, the secondary electrons generated by scanning the focused ion beam irradiated from the focused ion beam device were detected by a charged particle detector and observed in a state in which the contact was moved forward and backward.

  Here, the particles were fixed to the tip of the contact needle by deposition using diamond-like carbon.

  As described above, the adhesion force between the substrate and the particles was measured by measuring the pulling force of the particles fixed to the tip of the contact needle based on the displacement amount of the leaf spring. Here, the pulling direction was perpendicular to the substrate. The change amount measuring means was performed by measuring a displacement of a voltage by a piezoelectric element. The result measured by the above method is shown in FIG.

  As in Example 1, the adhesion force of polystyrene particles having a diameter of 0.02 μm to 1 μm adhered on the Si substrate was measured using the particle adhesion force measuring device of the present invention.

  In this embodiment, the means for fixing the particles to the tip of the leaf spring is a method performed by a manipulator. Charge is applied to the tip of the manipulator shown in FIG. In this embodiment, the tip of the manipulator is positively charged by applying an electric charge, the tip of the manipulator is opened by electrostatic repulsion, and after sandwiching the particles, the tip of the manipulator is closed by removing the charge, and the tip of the manipulator The particles were fixed to

  As described above, the adhesion force between the substrate and the particles was measured by measuring the pulling force of the particles fixed to the tip of the manipulator based on the displacement amount of the leaf spring. Here, the pulling direction was perpendicular to the substrate.

  The amount of change is measured by measuring the displacement of a laser displacement meter that emits laser light.

  The results measured by the above method are shown in FIG.

  The foreign matter adhering to the Si substrate was removed using the particle adhesion measuring device of the present invention similar to the case of Example 2.

  The apparatus used in this example includes a sample stage for fixing a Si substrate to which foreign matter is attached, a plate spring that is fixed with one end fixed, a contact needle that is fixed to the tip of the plate spring, An apparatus comprising: means for fixing the particles at a tip; and drive means for moving the contact forward and backward to contact and separate.

  Further, the particles were fixed to the tip of the contact needle. Then, the secondary electrons generated by scanning the focused ion beam irradiated from the focused ion beam device were detected by a charged particle detector and observed in a state in which the contact was moved forward and backward.

  Here, the particles were fixed to the tip of the contact needle by deposition using diamond-like carbon.

  As described above, the foreign matter was removed from the Si substrate by pulling the particles fixed to the tip of the contact needle. Here, the pulling direction was parallel to the substrate.

  The foreign matter was removed by the above method, the foreign matter on the Si substrate could be reduced, and the semiconductor device could be manufactured with a high yield.

  The present invention serves as a guideline for examining the cleaning means necessary for removing particles on the substrate, and makes it easier to manage the cleanliness of electronic devices such as magnetic disk devices that require higher cleanliness, resulting in higher yields. Can be manufactured.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a conceptual diagram of a particle adhesion measuring device of the present invention for explaining Example 1; It is a figure for demonstrating the method to fix a contact needle and particle | grains comprised in the particle | grain adhesion force measuring apparatus of this invention. It is a figure for demonstrating the method to fix a manipulator and particle | grains comprised in the particle | grain adhesion force measuring apparatus of this invention. It is a figure for demonstrating the measurement result by the particle | grain adhesion force measuring apparatus of this invention. It is a figure for demonstrating the measurement result by the particle | grain adhesion force measuring apparatus of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Particle, 2 ... Substrate, 3 ... Sample stand, 4 ... Leaf spring, 5 ... Contact needle, 6 ... Driving means, 7 ... Measuring means for measuring displacement of leaf spring, 8 ... Focused ion beam device, 9 ... Focusing Ion beam, 10 ... charged particle detector, 11 ... deposition device, 12 ... deposition region, 13 ... plus charge.

Claims (8)

  A sample stage for fixing a substrate to which particles are attached; a plate spring that is fixed with one end fixed; a contact needle that is fixed to the tip of the plate spring; and means for fixing the particles to the tip of the contact needle A particle adhesion force measuring apparatus comprising: drive means for moving the contact element back and forth to contact and separate; and measuring means for measuring the displacement of the tip of the leaf spring.   It is possible to detect and observe secondary electrons generated by scanning a focused ion beam to fix the particles to the tip of the contact needle and to make the contact move forward and backward. The particle adhesion measuring apparatus according to claim 1.   3. The particle adhesion measuring apparatus according to claim 1, wherein the means for fixing the particles to the tip of the contact needle is a deposition process.   The means for fixing the particles to the tip of the contact needle is performed by sandwiching a manipulator between the particles, and the operation of sandwiching the manipulator is performed by static electricity. Wear force measuring device.   The particle adhesion force measurement according to any one of claims 1 to 3, further comprising measurement means for measuring a force for pulling the particle fixed to the tip of the contact needle based on a displacement amount of the leaf spring. apparatus.   The change amount measuring means is a measurement of a change by a laser displacement meter that irradiates a laser beam or a measurement of a displacement of a voltage by a piezoelectric element, and measures the pulling force of the particles by the change amount. Item 6. The particle adhesion measuring apparatus according to Item 5.   5. The particle removing apparatus according to claim 1, further comprising means for removing the particles by pulling the particles fixed to the tip of the contact needle.   A device manufacturing method manufactured by the particle adhesion measuring apparatus according to claim 1 or the particle removing apparatus according to claim 7.

Images