JP2010016279A - Substrate measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain accurate measurements by supporting a substrate while being flattened, and easily bringing a measurement part close to the substrate. <P>SOLUTION: In this substrate measuring device, a first fluid is ejected toward a circumference of an object region 911 on an upper surface 91 of a substrate 9 from a first porous member 211, and a second fluid is ejected towards a lower surface 92 of the substrate 9 from a second porous member 221, facing the first porous member 211 by interposing the substrate 9. As a result, the substrate 9 can be supported between the first porous member 211 and the second porous member 221, while being flattened. By relatively moving vertically a measurement electrode 31 with respect to the first porous member 211 by a measurement part moving mechanism 4, the measurement electrode 31 can be brought easily and rapidly close to the substrate 9 to a desired position (a position where the distance between the measurement electrode 31 and the upper surface 91 of the substrate 9 is set to 0.3 μm) which makes it difficult to bring the measurement electrode close to the substrate only by the control of the first fluid, and thereby accurate measurement on C-V characteristics can be realized. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a substrate measuring apparatus that measures predetermined characteristics in a target region of a substrate.

  Conventionally, in the manufacture of semiconductor elements and flat display devices, various measurements have been performed on various substrates such as semiconductor substrates and glass substrates for flat display devices. CV characteristics of the semiconductor substrate by non-contact CV measurement (capacitance-voltage measurement) performed with the measurement electrodes held on the semiconductor substrate placed on the sample stage with a gap therebetween ( An apparatus for measuring capacitance-voltage characteristics is disclosed. In such an apparatus, in order to improve measurement accuracy, the measurement electrode is held in a state of being very close to the semiconductor substrate (for example, a state in which the distance between the measurement electrode and the semiconductor substrate is 1 μm or less). The

  In Patent Document 3, a sensor chip as an electrode is held with a gap on a semiconductor substrate placed on a stage-like back electrode, and measurement is performed while irradiating light to a measurement point below the sensor chip. An apparatus for measuring the doping profile and surface photovoltage of a semiconductor substrate by performing is disclosed. In the apparatus of Patent Document 3, when air is supplied to the air bearing, the air bearing assembly that holds the sensor chip is pushed down from the position of about 2 mm above the semiconductor substrate toward the semiconductor substrate, and is provided around the sensor chip. The air flowing from the orifice to the semiconductor substrate is supported by an air film formed between the air bearing assembly and the semiconductor substrate and floats at a position about 20 μm above the semiconductor substrate. Thereafter, the air bearing assembly is further lowered by stopping the outflow of air from the orifice, but is maintained by the air flowing toward the semiconductor substrate from the porous ring provided around the sensor chip outside the orifice. Due to the air film, the air bearing assembly floats about 2 μm above the semiconductor substrate, and the above measurement is performed in this state.

On the other hand, in Patent Document 4, information is recorded on a master by irradiating the master with an electron beam from an opposing electron beam irradiation head on a master of an optical disk placed on a rotary table via a minute gap. An apparatus for performing is disclosed. The apparatus of Patent Document 4 includes a floating pad that floats in a non-contact manner with respect to the master by ejecting compressed gas from a ring-shaped vent formed of a porous metal toward the upper surface of the master. The irradiation head is mounted on the flying pad. As a result, it is intended to reduce the influence of the thickness unevenness of the master and the rotational shake, and to maintain a gap between the electron beam irradiation head and the master. In the device of Patent Document 4, a ring-shaped suction groove is provided inside the ventilation body of the floating pad. By sucking air from the suction groove, the floating pad is positioned approximately 5 μm above the master. Yes.
JP-A-4-132236 Japanese Patent No. 2709351 JP-T-2001-505369 JP 2003-316017 A

  By the way, a substrate subjected to various processes such as film formation and annealing usually has a slight warp, inclination, etc., and is not completely flat. Therefore, as in Patent Document 1 and Patent Document 2, there is a limit to improvement in measurement accuracy in an apparatus that performs measurement on the assumption that the distance between the measurement electrode and the substrate is constant at any position. .

  On the other hand, in the apparatus of Patent Document 4, the distance between the beam irradiation head and the master is kept constant by floating the electron beam irradiation head on the master, but let the beam irradiation head be closer to the master. Then, it is necessary to control the ejection of compressed gas from the floating pad or the suction of air to move the entire floating pad downward, and it is difficult to control the position of the beam irradiation head with high accuracy.

  Similarly, in the apparatus of Patent Document 3, when adjusting the distance between the sensor chip and the semiconductor substrate, it is necessary to adjust the amount of air supplied to the air bearing assembly to raise and lower the entire air bearing assembly. Chip position control is complicated. Further, in the apparatus of Patent Document 3, when the sensor chip is positioned, the air supply is supplied after the air bearing assembly is lowered to a position of about 20 μm above the semiconductor substrate by controlling the amount of air supplied to the air bearing. Since the amount is controlled again to bring the air bearing assembly closer to the semiconductor substrate, it is difficult to quickly position the sensor chip. Furthermore, in the apparatus of Patent Document 3, the distance between the sensor chip and the semiconductor substrate is set to 2 μm. However, the lowering of the sensor chip is prevented by the resistance of the air film between the sensor chip and the semiconductor substrate. Only by controlling the air supply amount, it is difficult to bring the sensor chip and the semiconductor substrate closer to each other without contacting them, and there is a limit to improving the measurement accuracy.

  On the other hand, in the devices of Patent Document 1 to Patent Document 4, the electrodes and the beam irradiation head provided above the substrate are not in contact with the substrate, but the lower surface of the substrate is in contact with the entire surface of the sample table or the like. Therefore, there is a possibility that particles may adhere to the lower surface or be damaged. In addition, it is necessary to increase the size of the sample stage with the increase in size of the substrate. However, it is difficult to accurately form the upper surface on which the substrate is placed, which is necessary for manufacturing the sample stage. Cost increases.

  The present invention has been made in view of the above problems, and has as its main object to realize a highly accurate measurement by supporting the substrate while flattening it and easily bringing the measuring unit close to the substrate.

  The invention according to claim 1 is a substrate measuring apparatus for measuring a predetermined characteristic in a target region of the substrate, and is arranged from the first porous member toward the periphery of the target region on one main surface of the substrate. A first fluid ejecting portion that ejects one fluid, and a first fluid ejecting portion that is disposed opposite to the first fluid ejecting portion, and ejecting the second fluid from the second porous member toward the other main surface of the substrate, A second fluid ejecting portion for supporting the substrate in a non-contact manner between the first porous member and the second porous member; and an outer edge portion of the substrate in contact with the one main portion of the substrate. A movement restricting portion for restricting movement in a direction parallel to the surface, and moving the first fluid ejection portion relative to the substrate along the one main surface of the substrate to A target area changing mechanism to be changed, and the substrate attached to the first fluid ejection portion; When the measurement unit facing the target region and the measurement unit measure a predetermined characteristic of the target region, the measurement unit is moved to the first fluid ejection unit in a direction toward the one main surface of the substrate. A measuring unit moving mechanism that moves relative to the first main surface in a non-contact manner.

  Invention of Claim 2 is a board | substrate measuring apparatus of Claim 1, Comprising: The distance between the front-end | tip of the said measurement part and said one main surface of the said board | substrate is 5 micrometers by the said measurement part moving mechanism. The measurement part is close to the one main surface until it becomes less than the value.

  Invention of Claim 3 is a board | substrate measuring apparatus of Claim 1 or 2, Comprising: A said 2nd fluid ejection part is a said 2nd fluid toward a part of said other main surface of the said board | substrate. And move relative to the substrate together with the first fluid ejection portion.

  Invention of Claim 4 is a board | substrate measuring apparatus of Claim 3, Comprising: The said 1st porous member and the said 2nd porous member are the same shape, and the direction perpendicular | vertical to the said board | substrate Are overlapping.

  A fifth aspect of the present invention is the substrate measuring apparatus according to the third or fourth aspect, wherein the first fluid and the second fluid are gases, the substrate is a semiconductor substrate, and the second porous The material member is formed of a conductive or semi-conductive material, and the substrate measuring apparatus applies a voltage to a measurement electrode facing the target region of the measurement unit, and the measurement electrode A capacitance measuring unit that obtains a combined capacity with the second porous member; and an applied voltage in the target region based on an output from the capacitance measuring unit while changing an applied voltage applied to the measuring electrode. A calculation unit for obtaining a relationship with the combined capacity, a switching mechanism for switching supply of the second fluid to the second porous member of the second fluid ejection unit and suction of the fluid through the second porous member; Further equipped When the relationship is acquired, suction is performed through the second porous member by the switching mechanism, whereby the other main surface of the substrate is adsorbed to and electrically connected to the second porous member. When the second fluid ejecting portion moves relative to the substrate together with the first fluid ejecting portion by the target region changing mechanism, the second from the second porous member is caused by the switching mechanism. The fluid is ejected.

  Invention of Claim 6 is a board | substrate measuring apparatus of Claim 5, Comprising: The said board | substrate is a semiconductor substrate by which the insulating film was formed in said one main surface, The said measurement part is the said board | substrate. A light source unit that causes light to enter the target region; a light receiving unit that receives reflected light from the target region of light from the light source unit; and an insulating film in the target region based on an output from the light receiving unit. A film thickness calculator for determining the thickness.

  The invention according to claim 7 is the substrate measuring apparatus according to claim 3 or 4, wherein the first fluid and the second fluid are gases, and the substrate has an insulating film on the other main surface. A formed semiconductor substrate, wherein the substrate measuring device applies a potential to a measurement electrode facing the target region of the measurement unit; an auxiliary electrode attached to the second fluid ejection unit; An auxiliary electrode moving mechanism that moves the auxiliary electrode relative to the second fluid ejection portion in a direction toward the other main surface of the substrate; and vibrates the measurement electrode in a vibration direction toward the target region. A vibration unit; and a calculation unit that obtains a surface potential of the target region based on an electrode potential of the measurement electrode when the measurement electrode is vibrated and a displacement current from the measurement electrode or the auxiliary electrode, The surface potential is When the auxiliary electrode is moved, the auxiliary electrode is moved by the auxiliary electrode moving mechanism, and the tip of the auxiliary electrode comes into contact with the substrate main body of the substrate on the other main surface of the substrate. When the second fluid ejecting portion is moved relative to the substrate together with the first fluid ejecting portion by the target region changing mechanism, the auxiliary electrode is moved by the auxiliary electrode moving mechanism. Separated from the surface.

  The invention according to claim 8 is the substrate measuring apparatus according to claim 3 or 4, wherein the first fluid and the second fluid are gases, the substrate is a semiconductor substrate, and the second porous The material member is formed of a conductive or semi-conductive material, and the substrate measuring apparatus includes a potential applying unit that applies a potential to the measurement electrode facing the target region of the measurement unit, and the measurement electrode. The object based on a vibration part that vibrates in a vibration direction toward the target region, an electrode potential of the measurement electrode when the measurement electrode is vibrated, and a displacement current from the measurement electrode or the second porous member A calculation unit for obtaining a surface potential of the region, and a switching mechanism for switching supply of the second fluid to the second porous member of the second fluid ejection unit and suction of the fluid through the second porous member. further In addition, when the surface potential is obtained, the switching mechanism is sucked through the second porous member, whereby the other main surface of the substrate is adsorbed by the second porous member and is electrically And when the second fluid ejecting portion moves relative to the substrate together with the first fluid ejecting portion by the target region changing mechanism, the switching mechanism causes the second porous member to move from the second porous member. The second fluid is ejected.

  A ninth aspect of the present invention is the substrate measuring apparatus according to any one of the first to fourth aspects, further comprising a computing unit that computes an output from the measuring unit, wherein the first fluid and the first fluid Two fluids are gas, the said board | substrate is a semiconductor substrate, and the electrical characteristic of the said board | substrate in the said object area | region is acquired by the said calculating part based on the output from the said measurement part.

  A tenth aspect of the present invention is the substrate measuring apparatus according to any one of the first to ninth aspects, wherein the first porous member has an annular shape surrounding the target region.

  The invention according to claim 11 is the substrate measuring apparatus according to claim 10, wherein the first porous member is annular.

  A twelfth aspect of the present invention is the substrate measuring apparatus according to the tenth or eleventh aspect, wherein the first fluid ejection portion is located on the opposite side of the first porous member from the substrate. A closing portion for closing the space inside the mass member is provided.

  A thirteenth aspect of the present invention is the substrate measuring apparatus according to any one of the tenth to twelfth aspects, wherein a space between the measurement unit and the target region is an inert gas atmosphere or a reduced pressure atmosphere. The

  A fourteenth aspect of the present invention is the substrate measuring apparatus according to any one of the first to thirteenth aspects, further comprising an auxiliary support portion that auxiliaryly supports the substrate in the vicinity of the outer edge portion of the substrate.

  A fifteenth aspect of the present invention is the substrate measuring apparatus according to any one of the first to fourteenth aspects, wherein the measuring unit moving mechanism is fixed to the first fluid ejection unit and the measuring unit. A linear guide mechanism that guides the measurement unit while bringing the guide unit and the moving unit into a non-contact state by ejecting a supporting fluid toward a gap between the moving unit and the moving unit.

  A sixteenth aspect of the present invention is the substrate measuring apparatus according to any one of the first to fifteenth aspects, wherein the measuring unit moving mechanism moves the measuring unit by expanding and contracting in the moving direction of the measuring unit. A piezoelectric element is provided.

  In the present invention, the substrate can be supported while being flattened, and the measurement unit can be easily brought close to the substrate to realize high-precision measurement.

  FIG. 1 is a plan view showing a configuration of a substrate measuring apparatus 1 according to the first embodiment of the present invention. FIG. 2 is a longitudinal sectional view of the substrate measuring apparatus 1 cut at the position AA in FIG. The substrate measuring apparatus 1 is an apparatus for measuring CV characteristics (that is, capacity-voltage characteristics) of a disk-shaped semiconductor substrate 9 (hereinafter referred to as “substrate 9”) having an insulating film formed on the surface thereof. .

  As shown in FIGS. 1 and 2, the substrate measuring apparatus 1 is attached to a substrate support mechanism 2 that supports the substrate 9, and a first fluid ejection unit 21 that will be described later of the substrate support mechanism 2, and faces the substrate 9. A measurement unit 3 is provided. In the following description, on one main surface 91 (the upper main surface in FIG. 2, hereinafter referred to as “upper surface 91”) of the substrate 9 shown in FIG. A region to be measured for V characteristics is referred to as a “target region 911”.

  As shown in FIG. 2, the substrate support mechanism 2 is opposed to the first fluid ejection portion 21 disposed above the substrate 9 and the first fluid ejection portion 21 sandwiching the substrate 9 below the substrate 9. As shown in FIG. 1, the 1st fluid ejection part 21 is circular in planar view, and the 2nd fluid ejection part 22 arrange | positioned is provided. In the following description, the main surface 92 on the second fluid ejection portion 22 side of the substrate 9 shown in FIG. 2 (that is, the other main surface opposite to the upper surface 91) is referred to as a “lower surface 92”.

  The first fluid ejection part 21 is an annular shape surrounding the periphery of the target region 911 on the upper surface 91 of the substrate 9 and ejects fluid toward the periphery of the target region 911 (that is, a part of the upper surface 91). A porous member 211 is provided. The centers of the inner peripheral edge and the outer peripheral edge of the first porous member 211 coincide.

  The first fluid ejection part 21 further includes a first support block 212 that supports the first porous member 211 above the first porous member 211, and the first support block 212 includes the first porous member 211. The inside space (that is, the space inside the inner peripheral edge of the first porous member 211) is a closed portion that closes the first porous member 211 on the side opposite to the substrate 9.

  The second fluid ejection part 22 includes a second porous member 221 that faces the first porous member 211 of the first fluid ejection part 21 and ejects fluid toward a part of the lower surface 92 of the substrate 9. The second porous member 221 has the same shape as that of the first porous member 211 in plan view (that is, an annular shape in which the centers of the inner peripheral edge and the outer peripheral edge coincide with each other), and the first porous member 221 is first in the direction perpendicular to the substrate 9. It overlaps with the porous member 211.

  The second fluid ejection part 22 further includes a second support block 222 that supports the second porous member 221 below the second porous member 221, and the second support block 222 includes the second porous member. This is a closed portion that closes the space inside 221 (that is, the space inside the inner peripheral edge of the second porous member 221) on the side opposite to the substrate 9 of the second porous member 221. In plan view, the areas of the first porous member 211 and the second porous member 221 are smaller than the area of the substrate 9.

  The first porous member 211 is formed of a porous ceramic or the like, and the second porous member 221 is formed of a conductive porous material such as a conductive porous ceramic or a porous stainless material. The porosity of each of the first porous member 211 and the second porous member 221 is preferably 1% to 10% (more preferably 3% to 5%). The inner diameters of the first porous member 211 and the second porous member 221 are preferably 10 mm or more and 50 mm or less, and the outer diameters of both porous members are preferably 50 mm or more and 100 mm or less. However, the difference between the outer diameter and the inner diameter of both porous members is 10 mm or more.

  A substantially annular flow path (not shown) is formed inside the first porous member 211, and the flow path passes through the first supply flow path 214 formed inside the first support block 212. To the first fluid supply device (not shown). In the first fluid ejection part 21, a fluid (hereinafter referred to as “first fluid”) is supplied from the first fluid supply device to the flow path of the first porous member 211 via the first supply flow path 214. As a result, the first fluid is uniformly ejected from the entire lower surface of the first porous member 211 toward the upper surface 91 of the substrate 9. The first supply flow path 214 is also connected to a guide portion 421 (see FIG. 4) formed by a porous member of the air bearing 42 described later.

  A substantially annular flow path (not shown) is formed inside the second porous member 221, similarly to the first porous member 211, and the flow path is formed inside the second support block 222. The second supply flow path 224 and the switching mechanism 225 provided outside the second fluid ejection portion 22 are connected to a second fluid supply device (not shown) and a vacuum pump. In the second fluid ejection portion 22, the fluid to the flow path of the second porous member 221 is connected by connecting the second supply flow path 224 and the second fluid supply device by the switching mechanism 225 (in the following description, “ The second fluid is uniformly ejected from the entire upper surface of the second porous member 221 toward the lower surface 92 of the substrate 9. Further, the second supply channel 224 and the vacuum pump are connected by the switching mechanism 225, whereby the fluid around the second porous member 221 is sucked through the second porous member 221. As described above, in the substrate measuring apparatus 1, the supply of the second fluid to the second porous member 221 and the suction of the fluid through the second porous member 221 are switched by the switching mechanism 225.

In the substrate support mechanism 2, the first fluid and the second fluid are ejected from the first porous member 211 of the first fluid ejection part 21 and the second porous member 221 of the second fluid ejection part 22 toward the substrate 9. As a result, the substrate 9 is supported in a non-contact manner between the first porous member 211 and the second porous member 221. In the present embodiment, the first fluid and the second fluid ejected from the first porous member 211 and the second porous member 221 are gases (for example, nitrogen (N ₂ ) gas), and the first porous member The distance between 211 and the upper surface 91 of the substrate 9 (that is, the distance in the direction perpendicular to the substrate 9) is 5 μm or more and 30 μm or less. Further, the distance between the second porous member 221 and the lower surface 92 of the substrate 9 is also set to 5 μm or more and 30 μm or less. The first fluid and the second fluid may be the same fluid or different types of fluid.

  By the way, the substrate 9 has a slight warp and inclination due to various processes such as film formation and annealing, and is not completely flat. In the substrate support mechanism 2, the portion of the substrate 9 between the first porous member 211 and the second porous member 221 has the first fluid ejected from the first porous member 211 and the second porous member 221 and The second fluid is pressed and flattened from both upper and lower sides (that is, from the upper surface 91 and the lower surface 92).

  As shown in FIGS. 1 and 2, the substrate support mechanism 2 includes an annular guide portion 23 disposed around the substrate 9, and the guide portion 23 is arranged at the outer edge portion 93 of the substrate 9 at the outer periphery of the substrate 9. An annular movement restricting portion 231 that abuts or faces the entire surface of the substrate 9 and restricts movement in a direction parallel to the upper surface 91 and the lower surface 92 of the substrate 9 is provided. As shown in FIG. 2, the guide portion 23 also assists the substrate 9 in an auxiliary manner by bringing a plurality of support pins 233 into contact with the lower surface 92 of the substrate 9 in the vicinity of the outer edge portion 93 of the substrate 9. A support portion 232 is provided. In the present embodiment, three or more support pins 233 are arranged at an equiangular pitch.

  As shown in FIG. 1, the substrate support mechanism 2 includes a substrate rotation mechanism 24 that passes through the center of the substrate 9 and rotates the substrate 9 together with the guide portion 23 about the central axis perpendicular to the substrate 9. The substrate rotation mechanism 24 includes a first motor 241, a pulley 242 attached to the rotation shaft of the first motor 241, and an annular belt 243 that contacts the outer peripheral surface of the pulley 242 and the outer peripheral surface of the guide portion 23. In the substrate rotation mechanism 24, the pulley 242 is rotated clockwise in FIG. 1 by the first motor 241, so that the guide portion 23 is rotated together with the substrate 9 clockwise in FIG. 1 via the belt 243.

  FIG. 3 is a longitudinal sectional view of the substrate measuring apparatus 1 cut at a position BB in FIG. As shown in FIGS. 1 and 3, the substrate support mechanism 2 of the substrate measuring apparatus 1 moves the first fluid ejection part 21 and the second fluid ejection part 22 along the upper surface 91 and the lower surface 92 of the substrate 9 in FIG. The ejection part moving mechanism 25 which moves to the left-right direction is provided. As shown in FIG. 1, the ejection unit moving mechanism 25 is fixed to the second motor 251, a ball screw 252 connected to the second motor 251, a nut 253 screwed into the ball screw 252, and the nut 253. As shown in FIG. 3, the first arm 254 that holds the first fluid ejection part 21 is provided, and the second arm 255 that is fixed to the nut 253 and holds the second fluid ejection part 22 is provided. The first support block 212 of the first fluid ejection part 21 and the second support block 222 of the second fluid ejection part 22 are fixed to the first arm 254 and the second arm 255, respectively.

  In the ejection part moving mechanism 25 shown in FIG. 1, when the ball screw 252 is rotated by the second motor 251, the nut 253 moves along the ball screw 252, thereby the first arm 254 and the first fluid ejection part. 21 moves relative to the substrate 9 along a slider 256 provided in parallel to the ball screw 252. Further, the second arm 255 and the second fluid ejection part 22 shown in FIG. 3 also move relative to the substrate 9 along the slider 256 together with the first fluid ejection part 21.

  In the substrate measuring apparatus 1 shown in FIG. 1, the substrate 9 is rotated about the central axis by the substrate rotating mechanism 24, and the first fluid ejecting portion 21 and the second fluid ejecting portion 22 (see FIG. 1) are ejected by the ejecting portion moving mechanism 25. 2) moves along the upper surface 91 and the lower surface 92 (see FIG. 2) of the substrate 9, so that the measurement unit 3 attached to the first fluid ejection unit 21 moves relative to the substrate 9.

  As shown in FIG. 2, the measurement electrode 31 provided at the tip of the measurement unit 3 is directed to the upper surface 91 of the substrate 9 through the space inside the annular first porous member 211. 9 is included in a circular region inside the first porous member 211 in a plan view. In the substrate measuring apparatus 1, the target region 911 is changed on the upper surface 91 of the substrate 9 by the relative movement of the first fluid ejection unit 21 with respect to the substrate 9. That is, in the substrate support mechanism 2, the substrate rotation mechanism 24 and the ejection part moving mechanism 25 move the first fluid ejection part 21 relative to the substrate along the upper surface 91 of the substrate 9, thereby moving the target region 911. This is a target area changing mechanism to be changed.

  FIG. 4 is an enlarged longitudinal sectional view showing a portion in the vicinity of the measurement unit 3 of the substrate measuring apparatus 1 shown in FIG. 2, and the other related to CV measurement (that is, capacitance-voltage measurement) of the substrate measuring apparatus 1. The configuration is also shown. In FIG. 4, the first supply channel 214 and the second supply channel 224 are not shown for convenience of illustration (the same applies to FIGS. 6, 7, and 9).

  As shown in FIG. 4, the substrate measuring apparatus 1 includes a measuring unit moving mechanism 4 that moves the measuring unit 3 relative to the first fluid ejection unit 21 in a direction perpendicular to the upper surface 91 of the substrate 9, and performs measurement. The unit moving mechanism 4 includes a piezoelectric element 41 that moves the measuring electrode 31 of the measuring unit 3 by expanding and contracting in the vertical direction perpendicular to the upper surface 91 of the substrate 9 (that is, the moving direction of the measuring unit 3), and the measuring unit 3. An air bearing 42 is provided as a linear motion guide mechanism for guiding the motor in the moving direction. The air bearing 42 includes a cylindrical guide part 421 fixed to the inner peripheral surface of the first porous member 211 of the first fluid ejection part 21, and the measurement electrode 31 is fixed to the tip inside the guide part 421. The columnar electrode holding part 32 is arranged as a moving part facing the guide part 421 in a non-contact manner with the guide part 421.

  In the substrate measuring apparatus 1, the first fluid is supplied to the guide part 421 formed of the porous member via the first supply flow path 214 (see FIG. 2) described above, and is provided in the guide part 421 and the measurement part 3. The first fluid is ejected as a supporting fluid toward the gap between the electrode holding unit 32 and the electrode holding unit 32 of the measuring unit 3 is supported in a non-contact state with the guide unit 421. When the piezoelectric element 41 expands and contracts, the measurement electrode 31 moves in a moving direction perpendicular to the upper surface 91 of the substrate 9 while being guided by the air bearing 42.

  The substrate measuring apparatus 1 is also connected to the measurement electrode 31 facing the target region 911 and connected to the voltage application unit 51 for applying an AC voltage to the measurement electrode 31, the measurement electrode 31, and the second porous member 221 for measurement. A capacitance meter 52 that is a capacitance measurement unit that acquires a combined capacitance between the electrode 31 and the second porous member 221, and an output from the capacitance meter 52 while changing the voltage applied to the measurement electrode 31 from the voltage application unit 51. Based on the above, the characteristic calculation unit 53 for obtaining the relationship between the applied voltage and the combined capacitance in the target region 911 (that is, the CV characteristic) and the movement of the measurement electrode 31 by the piezoelectric element 41 of the measurement unit moving mechanism 4 are controlled. A movement control unit 54 is provided.

  Next, measurement of the CV characteristic of the target region 911 by the substrate measuring apparatus 1 will be described. FIG. 5 is a diagram showing a flow of measurement of CV characteristics. In the substrate measuring apparatus 1 shown in FIG. 4, first, the first fluid (nitrogen) is supplied to the first fluid ejection part 21, and the first fluid flows from the lower surface of the first porous member 211 toward the upper surface 91 of the substrate 9. Erupted. In parallel with the ejection of the first fluid, the second fluid supply device and the second supply flow path 224 (see FIG. 2) are connected by the switching mechanism 225, so that the second fluid ejection portion 22 is The fluid (nitrogen) is supplied, and the second fluid is ejected from the upper surface of the second porous member 221 toward the lower surface 92 of the substrate 9. Thereby, the board | substrate 9 is hold | maintained in the non-contact between the 1st porous member 211 and the 2nd porous member 221 (step S11).

  The distance between the lower surface of the first porous member 211 and the upper surface 91 of the substrate 9 and the distance between the upper surface of the second fluid ejection part 22 and the lower surface 92 of the substrate 9 are 5 μm or more as described above. 30 μm or less. Moreover, the space inside the 1st porous member 211 and the space inside the 2nd porous member 221 are made into inert gas atmosphere. On the other hand, the first fluid supplied to the first fluid ejection part 21 is also ejected from the inner peripheral surface of the guide part 421 of the air bearing 42, and the electrode holding part 32 of the measurement part 3 is not in contact with the guide part 421. Supported.

  Subsequently, the substrate rotating mechanism 24 and the ejecting portion moving mechanism 25 (see FIGS. 2 and 3) cause the second fluid ejecting portion 22 to move relative to the substrate 9 together with the first fluid ejecting portion 21, so that the substrate 9 The target area 911 of the upper surface 91 of the first fluid is located below the measurement electrode 31 of the measurement unit 3 attached to the first fluid ejection unit 21 and faces the measurement electrode 31 (step S12). As described above, since the space inside the first porous member 211 is an inert gas atmosphere, the space between the measurement electrode 31 of the measurement unit 3 and the target region 911 is also an inert gas atmosphere. In the first fluid ejection part 21, the space inside the first porous member 211 is substantially closed by the guide part 421 of the air bearing 42 and the electrode holding part 32 of the measurement part 3. 212, even if the space inside the first porous member 211 is not closed, the nitrogen gas ejected from the first porous member 211 and the guide portion 421 causes the measurement electrode 31 and the target region 911 to The space between them is an inert gas atmosphere.

  Next, the second supply channel 224 (see FIG. 2) is connected to the vacuum pump by the switching mechanism 225, whereby suction through the second porous member 221 of the second fluid ejection part 22 is performed, and the substrate 9 The lower surface 92 is adsorbed to the second porous member 221 (step S13). Thereby, the lower surface 92 of the board | substrate 9 and the 2nd porous member 221 contact, and are electrically connected.

  When the substrate 9 is adsorbed to the second porous member 221, a voltage is applied from the voltage application unit 51 to the measurement electrode 31 of the measurement unit 3, and in this state, the measurement electrode 31 is positioned in the moving direction (step S14). ). Hereinafter, a voltage applied to the measurement electrode 31 when the measurement electrode 31 is positioned is referred to as a “positioning voltage”, and the positioning voltage is the same as the measurement electrode 31 and the second porous member 221 even when the voltage varies slightly. The value of the composite capacity between the values is in a range where there is almost no fluctuation.

  The measurement electrode 31 is positioned according to the following procedure. If the target value of the distance between the measurement electrode 31 and the upper surface 91 of the substrate 9 is set to 0.3 μm, for example, the distance between the measurement electrode 31 and the upper surface 91 of the substrate 9 is 0.3 μm. The combined capacity between the measurement electrode 31 and the second porous member 221 when the positioning voltage is applied to the measurement electrode 31 is obtained by theoretical calculation and stored in advance in the movement control unit 54. Then, the piezoelectric element 41 is controlled by the movement control unit 54 in a state in which the positioning voltage is applied to the measurement electrode 31, and the measurement electrode 31 moves in the direction toward the upper surface 91 of the substrate 9 together with the electrode holding unit 32. It approaches the upper surface 91 of the non-contact.

  In the substrate measuring apparatus 1, a combined capacity (hereinafter referred to as “measured combined capacity”), which is an output from the capacitance meter 52, is sent to the movement control unit 54 in parallel with the movement of the measurement electrode 31. Is compared with a theoretical value (hereinafter referred to as “target composite capacity”) of the composite capacity stored in advance. Then, the measurement electrode 31 is brought closer to the upper surface 91 of the substrate 9 until the measurement composite capacity becomes equal to the target composite capacity, whereby the distance between the measurement electrode 31 and the target region 911 is set to 0.3 μm. The positioning of 31 is completed.

  When the positioning of the measurement electrode 31 is completed, the applied voltage applied to the measurement electrode 31 by the voltage application unit 51 gradually increases or decreases within a predetermined range, and the measurement electrode 31 and the second porous member are measured by the capacitance meter 52. The combined capacity with 221 is continuously acquired. The output from the capacitance meter 52 is sent to the characteristic calculation unit 53, and the characteristic calculation unit 53 obtains the relationship between the applied voltage and the combined capacitance in the target region 911 (that is, the CV characteristic) (step S15).

  In the characteristic calculation unit 53, the gap between the measurement electrode 31 and the substrate 9 is obtained with respect to the CV characteristic obtained in step S15 by the method described in Japanese Patent Application Laid-Open No. 4-132236 and Japanese Patent No. 2709351. And the influence due to the difference in work function between the measurement electrode 31 and the substrate body of the substrate 9 is corrected by correcting the voltage due to the electric charge in the insulating film and the work function difference between the measurement electrode 31 and the substrate body of the substrate 9. A CV characteristic substantially equal to the CV characteristic acquired by the contact-type substrate measuring apparatus of the type in contact with the upper surface 91 of the substrate 9 is required.

  When the CV characteristic of the target region 911 is obtained, the measurement electrode 31 moves in a direction away from the upper surface 91 of the substrate 9 due to the contraction of the piezoelectric element 41 (step S16). Subsequently, the second fluid supply device and the second supply flow path 224 are connected by the switching mechanism 225, whereby the second fluid is supplied to the second fluid ejection portion 22, and from the upper surface of the second porous member 221. The second fluid is ejected toward the lower surface 92 of the substrate 9. Thereby, the 2nd porous member 221 leaves | separates from the board | substrate 9, and the board | substrate 9 is hold | maintained in the non-contact between the 1st porous member 211 and the 2nd porous member 221 (step S17).

  When there is a next measurement point, the process returns to step S12, and the first fluid ejection part 21 and the second fluid ejection part 22 are moved relative to the substrate 9 by the substrate rotation mechanism 24 and the ejection part movement mechanism 25. Thus, the target area 911 is changed (steps S18 and S12). And after adsorption | suction of the board | substrate 9 by the 2nd porous member 221, positioning of the measurement electrode 31, and acquisition of the CV characteristic were performed similarly to the above (step S13-S15), the measurement electrode 31 is a board | substrate. 9 is moved in a direction away from 9, and the substrate 9 is held in a non-contact manner between the first porous member 211 and the second porous member 221 (steps S16 and S17). Thus, in the board | substrate measuring apparatus 1, acquisition of a CV characteristic is sequentially performed with respect to several measurement points.

  As described above, in the substrate support mechanism 2 of the substrate measuring apparatus 1, the first porous member 211 of the first fluid ejection part 21 is firstly directed toward the periphery of the target region 911 on the upper surface 91 of the substrate 9. The fluid is ejected, and the second fluid is ejected from the second porous member 221 of the second fluid ejection portion 22 facing the first fluid ejection portion 21 across the substrate 9 toward the lower surface 92 of the substrate 9. Accordingly, the substrate 9 can be supported between the first fluid ejection part 21 and the second fluid ejection part 22 while being planarized (that is, while the target region 911 is planarized).

  Further, the distance between the substrate 9 and the first porous member 211 of the first fluid ejection part 21 can be kept constant with a simple structure without providing another mechanism such as an autofocus mechanism. As a result, the measurement electrode 31 of the measurement unit 3 can be easily and quickly moved to a position close to the substrate 9 (in this embodiment, a position where the distance between the measurement electrode 31 and the upper surface 91 of the substrate 9 is 5 μm to 30 μm). Therefore, the work time required for focus adjustment and the like can be reduced, and the measurement speed can be increased.

  By the way, in the substrate measuring apparatus 1, the first porous member 211 is controlled only by controlling the ejection amount of the first fluid due to the resistance of the first fluid (nitrogen gas) layer between the measurement electrode 31 and the upper surface 91 of the substrate 9. It is difficult to bring the first porous member 211 closer to the upper surface of the substrate 9 without bringing the substrate 9 into contact with the substrate 9. Therefore, since the area in plan view is smaller than that of the first porous member 211, the measurement electrode 31 having a small resistance of the nitrogen gas layer between the upper surface 91 of the substrate 9 and the measurement unit moving mechanism 4 is used as described above. By moving relatively with respect to the first porous member 211, the first porous member 211 protrudes from the lower surface of the first porous member 211 toward the substrate 9, and further close to the substrate 9 (in this embodiment, the measurement electrode 31. And a position where the distance between the substrate 9 and the upper surface 91 of the substrate 9 is 0.3 μm).

  As described above, in the substrate measuring apparatus 1, the resistance of the nitrogen gas layer makes it difficult to maintain a non-contact state by fluid control alone (that is, the measurement electrode 31 at the tip of the measurement unit 3 and the substrate 9 are not close to each other). The measurement electrode 31 is close to the upper surface 91 of the substrate 9 until the distance between the upper surface 91 and the upper surface 91 is less than 5 μm, so that the CV characteristic can be measured with high accuracy. Therefore, the structure of the substrate measuring apparatus 1 is particularly suitable for an apparatus that requires the measuring unit to be close to the upper surface of the substrate to the extent that the distance between the tip of the measuring unit and the upper surface of the substrate is less than 5 μm.

  In the case of a conventional substrate holding apparatus that holds the entire lower surface of the substrate by suction, there is a possibility that particles adhere to the entire lower surface of the substrate that contacts the stage of the substrate holding apparatus or are damaged. On the other hand, in the substrate support mechanism 2 of the substrate measuring apparatus 1 according to the present embodiment, the second porous member 221 is not in contact with the substrate 9 except when measuring the CV characteristics. 9 can be prevented from adhering to the lower surface 92 and damage to the lower surface 92.

  In the substrate measuring apparatus 1, the first fluid ejection unit 21 is moved relative to the upper surface 91 of the substrate 9 by the substrate rotation mechanism 24 and the ejection unit moving mechanism 25, so that the target region 911 that is a measurement target of the CV characteristic. Is changed. At this time, the first fluid ejection portion 21 can be quickly moved relatively without contacting the substrate 9, so that the target region 911 can be changed quickly. As a result, the CV characteristics at a plurality of measurement points on the substrate 9 can be quickly measured.

  In the substrate measuring apparatus 1, the second fluid ejection part 22 ejects the second fluid from the second porous member 221 toward a part of the lower surface 92 of the substrate 9, and together with the first fluid ejection part 21, the substrate 9. Therefore, the second porous member 221 of the second fluid ejection part 22 can be reduced in size. Furthermore, the electrode 9 on the lower surface 92 side of the substrate 9 can be installed with a simple structure by adsorbing the substrate 9 with the conductive second porous member 221 only when measuring the CV characteristics. Can do.

  In the case of the conventional substrate holding apparatus described above, when the substrate is enlarged, the stage for holding the substrate needs to be enlarged. However, it is difficult to accurately form the upper surface of the large stage, and a large cost is required to manufacture a high-precision large stage. On the other hand, in the substrate support mechanism 2 of the substrate measuring apparatus 1 according to the present embodiment, the second porous member 221 can be reduced in size, so that even when a relatively large substrate is supported. The upper surface of the second porous member 221 (that is, the surface facing the lower surface 92 of the substrate 9) can be formed with high accuracy while reducing the manufacturing cost as compared with the stage of the conventional substrate holding apparatus. As a result, planarization of the substrate 9 between the first porous member 211 and the second porous member 221 can be realized with higher accuracy. In addition, a desired contact area between the lower surface 92 of the substrate 9 and the second porous member 221 can be ensured.

  In the substrate measuring apparatus 1, the second porous member 221 has the same shape as the first porous member 211, and the second porous member 221 is disposed so as to overlap the first porous member 211 in the central axis direction. Thereby, in the 1st porous member 211 and the 2nd porous member 221, the part which does not contribute to planarization of the board | substrate 9 is omitted, and both the 1st porous member 211 and the 2nd porous member 221 are reduced in size. Can do.

  In the first fluid ejection part 21, the first porous member 211 is formed in an annular shape surrounding the periphery of the target region 911, so that the uniformity of the pressing force on the substrate 9 around the target region 911 can be improved. The substrate 9 can be further flattened between the first fluid ejection part 21 and the second fluid ejection part 22. Further, since the first porous member 211 has an annular shape, the uniformity of the pressing force on the substrate 9 around the target region 911 can be further improved, and the first fluid ejection portion 21 and the second fluid ejection can be performed. The substrate 9 can be further planarized with the portion 22. As a result, the CV characteristic of the substrate 9 can be measured with higher accuracy in the substrate measuring apparatus 1.

  Moreover, in the 1st fluid ejection part 21, the 1st porous member 211 can also be easily formed because the 1st porous member 211 is made into an annular | circular shape. Similarly, in the second fluid ejection portion 22, the second porous member 221 is formed in an annular shape, whereby the target region 911 can be further flattened and the second porous member 221 can be easily formed. Can do.

  In the first fluid ejection part 21, the space inside the first porous member 211 is closed by the first support block 212, so that floating particles or the like may adhere to the target region 911 during CV characteristic measurement. In addition to being prevented, it is easily realized that the space on the target area 911 has an atmosphere suitable for measurement. In addition, as described above, since the first fluid is nitrogen gas and the space inside the first porous member 211 is an inert gas atmosphere, it is possible to measure CV characteristics with higher accuracy. Is done.

  In the substrate measuring apparatus 1, the distance between the first porous member 211 and the upper surface 91 of the substrate 9 and the distance between the second porous member 221 and the lower surface 92 of the substrate 9 are 5 μm or more. Accordingly, it is possible to reliably prevent the first porous member 211 and the second porous member 221 from coming into contact with the substrate 9 when the first fluid ejection part 21 and the second fluid ejection part 22 are moved. In addition, when the distance is 30 μm or less, the portion of the substrate 9 between the first porous member 211 and the second porous member 221 can be sufficiently flattened.

  Further, in the substrate support mechanism 2, the structure of the substrate support mechanism 2 is simplified by using the first fluid and the second fluid ejected from the first fluid ejecting section 21 and the second fluid ejecting section 22 as gas. be able to. Furthermore, by providing the auxiliary support portion 232 that supports the substrate 9 in an auxiliary manner, the substrate 9 can be more easily supported than when the substrate 9 is supported only by the first fluid ejection portion 21 and the second fluid ejection portion 22. It can be supported stably.

  In the measurement unit moving mechanism 4 of the substrate measuring apparatus 1, the air bearing 42 is used as a linear motion guide mechanism that guides the measurement electrode 31 of the measurement unit 3 in the movement direction, thereby moving the measurement electrode 31 in the movement direction. It can be performed with high accuracy. In addition, friction between the electrode holding portion 32 and the guide portion 421 during movement of the measurement electrode 31 is prevented, and contamination of the substrate 9 due to particles or the like caused by friction is prevented. Furthermore, by moving the measuring electrode 31 by the piezoelectric element 41 in the measuring unit moving mechanism 4, the measuring electrode 31 is moved in the moving direction with higher accuracy.

  Next, a substrate measuring apparatus according to a second embodiment of the present invention will be described. FIG. 6 is a longitudinal sectional view showing a part of the substrate measuring apparatus 1a according to the second embodiment, and corresponds to FIG. 4 of the substrate measuring apparatus 1 according to the first embodiment. As shown in FIG. 6, in the substrate measuring apparatus 1a, in addition to the components of the substrate measuring apparatus 1 shown in FIGS. 1 to 4, the measuring unit 3 includes a light source unit 33, a light receiving unit 34, and a film thickness that constitute an ellipsometer. A calculation unit 35 is provided. Other configurations are the same as those of the substrate measuring apparatus 1 shown in FIGS. 1 to 4, and the same reference numerals are given to corresponding configurations in the following description. In FIG. 6, for convenience of illustration, the voltage application unit 51, the capacitance meter 52, the characteristic calculation unit 53, and the movement control unit 54 are omitted.

  The light source unit 33 includes a semiconductor laser (LD) and an electromagnetic shutter (not shown). When the electromagnetic shutter is open, light from the semiconductor laser passes through a through hole formed in the first fluid ejection unit 21. Then, the light is incident on the target region 911 of the substrate 9 obliquely (that is, inclined with respect to the upper surface 91 of the substrate 9). Reflected light from the target region 911 of light from the light source unit 33 is incident on and received by the light receiving unit 34 through another through hole formed in the first fluid ejection unit 21.

  The light receiving unit 34 includes a quarter-wave plate array (hereinafter referred to as “λ / 4 plate array”) and a polarizer array, and a CCD (Charge Coupled Device) formed of a photonic crystal (not shown). In the λ / 4 plate array, a plurality of regions having different crystal axes are arranged in stripes, and in the polarizer array, a plurality of regions having different crystal axes are arranged in stripes. The polarizer array is arranged so that the arrangement direction of the plurality of stripe-shaped regions is perpendicular to the arrangement direction of the plurality of stripe-shaped regions of the λ / 4 plate array.

  In the substrate measuring apparatus 1 a, the light source unit 33 and the light receiving unit 34 are fixed to the electrode holding unit 32 via support members 331 and 341, respectively, and the measurement electrode 31 and the electrode holding unit are held by the piezoelectric element 41 of the measuring unit moving mechanism 4. It moves together with the part 32 in the vertical direction perpendicular to the upper surface 91 of the substrate 9 (that is, the movement direction of the measurement electrode 31).

  The measurement of the CV characteristic of the target region 911 by the substrate measuring apparatus 1a is substantially the same as in the first embodiment, but between the step S14 and step S16 shown in FIG. 34 and the film thickness calculator 35 are different in that the thickness of the insulating film in the target region 911 is obtained.

  In the substrate measuring apparatus 1a, the focus adjustment is performed by moving the light source unit 33 and the light receiving unit 34 in the vertical direction by the measurement unit moving mechanism 4, and then the light emitted from the semiconductor laser of the light source unit 33 is the substrate 9. Reflected light that is incident on the upper target region 911 and reflected by the target region 911 enters the CCD through the λ / 4 plate array and the polarizer array of the light receiving unit 34. Then, the intensity of the light transmitted through the combination of the λ / 4 plate having various crystal axes and the polarizer (that is, data indicating the polarization state of the reflected light) is acquired by the CCD and output to the film thickness calculator 35. Then, the thickness calculator 35 obtains the thickness of the insulating film in the target region 911 based on the output by the ellipsometry. The thickness of the insulating film obtained by the film thickness calculator 35 is sent to the characteristic calculator 53 (see FIG. 4), and is used when the CV characteristic is obtained by the characteristic calculator 53.

  In the substrate measuring apparatus 1a according to the second embodiment, as in the first embodiment, the substrate 9 is supported while being flattened, and is measured to a position where it is difficult to make the substrate 9 approachable only by controlling the first fluid. The measurement electrode 31 of the unit 3 can be brought close to the substrate 9 easily and quickly, thereby realizing highly accurate CV characteristic measurement. In addition, the C-V characteristic measurement speed can be increased.

  In the substrate measuring apparatus 1a, in particular, the thickness of the insulating film in the target region 911 is obtained with high accuracy by the ellipsometer (that is, the light source unit 33, the light receiving unit 34, and the film thickness calculating unit 35) provided in the measuring unit 3. Thus, the CV characteristic can be measured with higher accuracy. Moreover, the structure of the board | substrate measuring apparatus 1a is simplified by utilizing the measurement part moving mechanism 4 which moves the measurement electrode 31 for the focus adjustment of an ellipsometer. In the substrate measuring apparatus 1a, the measurement unit 3 may be provided with a configuration for measuring the film thickness by the optical interference method instead of the ellipsometer.

  Next, a substrate measuring apparatus according to a third embodiment of the present invention will be described. FIG. 7 is a longitudinal sectional view showing a part of the substrate measuring apparatus 1b according to the third embodiment, and corresponds to FIG. 4 of the substrate measuring apparatus 1 according to the first embodiment. The substrate measuring device 1b is a device that measures the surface potential of the target region 911 of the substrate 9 having an insulating film formed on the upper surface 91 by a vibration capacitance method which is one of AC methods.

  In the substrate measuring apparatus 1b, a potential is applied to the measuring electrode 31 of the measuring unit 3 as shown in FIG. 7 instead of the voltage applying unit 51, the capacitance meter 52, and the characteristic calculating unit 53 of the substrate measuring apparatus 1 shown in FIG. A potential applying unit 55, a processing unit 57 that is a set of circuits and devices for processing various electrical signals, and a surface potential calculating unit 56 that obtains the surface potential of the target region 911. The processing unit 57 is a measurement electrode. 31 and the second porous member 221 having conductivity. Other configurations are the same as those of the substrate measuring apparatus 1 shown in FIGS. 1 to 4, and the same reference numerals are given to corresponding configurations in the following description.

  FIG. 8 is a diagram showing a flow of surface potential measurement by the substrate measuring apparatus 1b. When the surface potential is measured, the first fluid is supplied to the first fluid ejecting portion 21 from the lower surface of the first porous member 211 to the upper surface 91 of the substrate 9 as in the first embodiment. A 1st fluid is ejected toward. In parallel with the ejection of the first fluid, the second fluid supply device and the second supply flow path 224 (see FIG. 2) are connected by the switching mechanism 225, so that the second fluid ejection portion 22 is The fluid is supplied and the second fluid is ejected from the upper surface of the second porous member 221 toward the lower surface 92 of the substrate 9. Thereby, the board | substrate 9 is hold | maintained in the non-contact between the 1st porous member 211 and the 2nd porous member 221 (step S21).

  Subsequently, the substrate rotating mechanism 24 and the ejecting portion moving mechanism 25 (see FIGS. 2 and 3) cause the second fluid ejecting portion 22 to move relative to the substrate 9 together with the first fluid ejecting portion 21, so that the substrate 9 The target area 911 of the upper surface 91 is located below the measurement electrode 31 of the measurement unit 3 attached to the first fluid ejection unit 21 and faces the measurement electrode 31 (step S22).

  Next, the second supply flow path 224 is connected to the vacuum pump by the switching mechanism 225, whereby suction through the second porous member 221 of the second fluid ejection portion 22 is performed, and the lower surface 92 of the substrate 9 is Adsorbed to the two porous members 221 (step S23). Thereby, the lower surface 92 of the substrate 9 and the second porous member 221 are electrically connected.

  When the substrate 9 is adsorbed to the second porous member 221, the measurement electrode 31 is moved toward the upper surface 91 of the substrate 9 by the piezoelectric element 41 of the measurement unit moving mechanism 4, and the measurement electrode 31 is moved to the first porous member 211. Is located at a desired position closer to the upper surface 91 of the substrate 9 than the lower surface of the substrate (step S24). Then, the piezoelectric element 41 starts vibration of the measurement electrode 31 in the vertical direction toward the substrate 9 (that is, the vibration direction), and a minute current (measurement) output from the second porous member 221 to the processing unit 57. This is an alternating current generated due to a change in the capacitance between the measurement electrode 31 and the substrate 9 due to the vibration of the electrode 31, and is hereinafter referred to as a “displacement current”) to be a predetermined value. The potential applied to the measurement electrode 31 from the potential applying unit 55 (hereinafter referred to as “electrode potential”) is controlled, and the electrode potential is acquired by the surface potential calculating unit 56. In the substrate measuring apparatus 1b, the piezoelectric element 41 is a vibrating part that vibrates the measuring electrode 31 in the vertical direction toward the target region 911. In addition to the piezoelectric element 41, a vibration part that vibrates the measurement electrode 31 in the vertical direction may be provided.

  When the acquisition of the electrode potential is completed, the change of the specified value of the displacement current and the acquisition of the electrode potential are repeated a plurality of times, whereby the relationship between the displacement current and the electrode potential when the measurement electrode 31 is vibrated (that is, a plurality of The surface potential in the target region 911 of the substrate 9 is obtained by the surface potential calculation unit 56 based on the relationship (step S25).

  When the surface potential of the target region 911 is obtained, the measurement electrode 31 moves in a direction away from the upper surface 91 of the substrate 9 (step S26). Subsequently, the second fluid is ejected from the upper surface of the second porous member 221 toward the lower surface 92 of the substrate 9, the second porous member 221 is separated from the substrate 9, and the substrate 9 is separated from the first porous member 211. The second porous member 221 is held in a non-contact manner (step S27).

  When there is a next measurement point, the process returns to step S22, the first fluid ejection part 21 and the second fluid ejection part 22 move relative to the substrate 9, and the target area 911 is changed (step S28). , S22). In the same manner as described above, after the adsorption of the substrate 9 by the second porous member 221, the movement of the measurement electrode 31, and the acquisition of the surface potential are performed (Steps S <b> 23 to S <b> 25), the measurement electrode 31 is removed from the substrate 9. The substrate 9 is moved away from the substrate 9 and is held in a non-contact manner (steps S26 and S27). Thus, in the board | substrate measuring apparatus 1b, acquisition of surface potential is sequentially performed with respect to several measurement points.

  In the substrate measuring apparatus 1b according to the third embodiment, as in the first embodiment, the substrate 9 is supported while being flattened, and is measured to a position where it is difficult to bring the substrate 9 close by only controlling the first fluid. The measurement electrode 31 of the unit 3 can be brought close to the substrate 9 easily and quickly, whereby high-precision surface potential measurement can be realized and the surface potential measurement speed can be increased. In addition, when the substrate 9 is adsorbed by the conductive second porous member 221 only when the surface potential is measured, conduction with the lower surface 92 of the substrate 9 can be realized with a simple structure. Furthermore, since the second porous member 221 is not in contact with the substrate 9 except when measuring the surface potential, it is possible to suppress adhesion of particles to the lower surface 92 of the substrate 9 and damage to the lower surface 92. By changing the target region 911 quickly, the surface potential at a plurality of measurement points on the substrate 9 can be measured quickly.

  Next, a substrate measuring apparatus according to a fourth embodiment of the present invention will be described. FIG. 9 is a longitudinal sectional view showing a part of the substrate measuring apparatus 1c according to the fourth embodiment, and corresponds to FIG. 4 of the substrate measuring apparatus 1 according to the first embodiment. The substrate measuring apparatus 1c uses the same vibration capacitance method as that of the substrate measuring apparatus 1b according to the third embodiment to determine the surface potential of the target region 911 on the upper surface 91 of the substrate 9 having the insulating film formed on the upper surface 91 and the lower surface 92. It is a device to measure in.

  In the substrate measuring device 1c, the switching mechanism 225 of the substrate measuring device 1b shown in FIG. 7 is omitted, and the second porous member 221 of the second fluid ejection part 22 shown in FIG. 9 is connected only to the second fluid supply device. . Further, the needle-like auxiliary electrode 61 having a sharp tip facing the lower surface 92 of the substrate 9 and the auxiliary electrode 61 are moved relative to the second fluid ejection part 22 in the direction toward the lower surface 92 of the substrate 9. An air cylinder 62 that is an auxiliary electrode moving mechanism is attached to the second fluid ejection portion 22. Other configurations are the same as those of the substrate measuring apparatus 1b shown in FIG. 7, and the same reference numerals are given to the corresponding configurations in the following description.

  The flow of the surface potential measurement by the substrate measuring apparatus 1c is substantially the same as the flow shown in FIG. 8, but the auxiliary electrode 61 is replaced by the air cylinder 62 instead of the adsorption of the substrate 9 by the second porous member 221 in step S23. The substrate 9 is moved toward the lower surface 92 of the substrate 9, and the tip of the auxiliary electrode 61 penetrates the insulating film on the lower surface 92 of the substrate 9 to come into contact with the substrate main body to be electrically connected to the substrate main body. In step S25, the surface potential calculation unit 56 obtains the surface potential in the target region 911 based on the relationship between the electrode potential of the measurement electrode 31 and the displacement current from the auxiliary electrode 61 when the measurement electrode 31 is vibrated. It is done. Then, instead of separating the second porous member 221 from the substrate 9 in step S <b> 27, the auxiliary electrode 61 is moved by the air cylinder 62 and separated from the lower surface 92 of the substrate 9.

  In the substrate measuring apparatus 1c according to the fourth embodiment, as in the first embodiment, the substrate 9 is supported while being flattened, and is measured to a position where it is difficult to make the substrate 9 approachable only by controlling the first fluid. The measurement electrode 31 of the unit 3 can be brought close to the substrate 9 easily and quickly, thereby realizing a highly accurate surface potential measurement. In addition, speeding up of surface potential measurement is realized.

  In the substrate measuring apparatus 1c, in particular, even when an insulating film is formed on the lower surface 92 of the substrate 9, the auxiliary electrode 61 can surely obtain electrical connection with the substrate body of the substrate 9, and the higher accuracy. Measurement of the surface potential can be realized. Further, when the first fluid ejecting portion 21 and the second fluid ejecting portion 22 are relatively moved with respect to the substrate 9 and when the surface potential is obtained, the substrate 9 always has the first porous member 211 and the second porous member. Since the contact with the lower surface 92 of the substrate 9 at the time of measuring the surface potential is small with only the tip of the needle-like auxiliary electrode 61, adhesion of particles to the lower surface 92 of the substrate 9, etc. Can be more reliably suppressed.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to the said embodiment, A various change is possible.

  For example, in the substrate measuring apparatus according to the above-described embodiment, the first fluid ejection unit 21 to which the measurement unit 3 is attached does not necessarily need to be disposed on the upper side in the gravity direction of the substrate 9. 21 may be disposed below the substrate 9, and the second fluid ejection part 22 may be disposed above the substrate 9.

  Further, in the substrate measuring apparatus, an exhaust device is connected to the first support block 212 of the first fluid ejection portion 21, and the space inside the first porous member 211 (that is, the space on the target region 911) is a reduced pressure atmosphere ( Including a vacuum atmosphere). In the case of a vacuum atmosphere, since the first fluid flows into the space inside the first porous member 211 from the first porous member 211, the guide portion 421, and the like, the space becomes a weak vacuum atmosphere.

  In the measurement unit moving mechanism 4 of the substrate measuring apparatus, another mechanism for moving the measurement electrode 31 in the movement direction may be provided instead of the piezoelectric element 41, and another guide mechanism may be provided instead of the air bearing 42. May be. Moreover, in the board | substrate measuring apparatus 1c which concerns on 4th Embodiment, it replaces with the air cylinder 62 as an auxiliary electrode movement mechanism, for example, even if another mechanism is provided like the mechanism which combined the motor and the cam. Good.

  In the substrate support mechanism 2 of the substrate measuring apparatus, the first fluid ejection part 21 and the second fluid ejection part 22 do not necessarily have to be connected, and a moving mechanism that moves the second fluid ejection part 22 is a first fluid. It may be provided independently of the moving mechanism that moves the ejection part 21, and both moving mechanisms may be driven in synchronization. Moreover, when a magnet is incorporated in the first fluid ejection part 21 and the second fluid ejection part 22 and the first fluid ejection part 21 is moved by the moving mechanism, the second fluid ejection part 22 is ejected by the magnetic force. The structure may be configured to move following the portion 21.

  In the substrate support mechanism 2, the positions of the first fluid ejection part 21 and the second fluid ejection part 22 are fixed, and the substrate is moved in the horizontal direction (that is, the direction parallel to the upper surface 91 and the lower surface 92 of the substrate 9). Accordingly, the relative movement of the first fluid ejection part 21 and the second fluid ejection part 22 with respect to the substrate may be realized. Thereby, the structure which concerns on the relative movement of the 1st fluid ejection part 21 and the 2nd fluid ejection part 22 can be simplified. On the other hand, by using the structure in which the first fluid ejection part 21 and the second fluid ejection part 22 are moved as in the above-described substrate processing apparatus, the foot stamp of the apparatus can be reduced in size.

  The auxiliary support part 232 of the substrate support mechanism 2 may be provided separately from the movement restriction part 231. Further, the auxiliary support portion 232 may be omitted from the substrate support mechanism 2, and the substrate 9 may be supported only by the first fluid ejection portion 21 and the second fluid ejection portion 22.

  The movement restricting portion 231 does not necessarily need to be in contact with or face the entire outer periphery of the substrate 9. For example, the movement restricting portion 231 is separated from each other on the outer periphery of the substrate 9 at three points (or four or more points). You may contact | abut or oppose the said outer peripheral surface. Further, the movement restricting portion 231 does not necessarily need to contact the outer peripheral surface of the substrate 9 as long as it contacts the outer edge portion 93 of the substrate 9. The movement of the substrate 9 may be restricted by friction between the lower surface 92 of the substrate 9 and the movement restricting portion due to the weight of the substrate 9. In this case, the auxiliary support part 232 of the substrate support mechanism 2 may also serve as a movement restriction part.

  The shape of the first porous member 211 and the second porous member 221 may be an annular shape in which the center of the inner peripheral edge is shifted from the center of the outer peripheral edge (that is, an annular shape in which the inner space is eccentric). . The first porous member 211 and the second porous member 221 do not necessarily have an annular shape, and may have an annular shape (for example, a rectangular frame shape) having other external shapes. The shape may be as follows. For example, the first fluid may be ejected around the target region 911 by the U-shaped first porous member 211 that sandwiches the target region 911 in plan view. Further, the first porous member 211 may be two parallel bar-shaped porous members facing each other with the target region 911 interposed therebetween.

  In the substrate support mechanism 2, the first porous member 211 and the second porous member 221 do not necessarily have the same shape. For example, the second fluid ejection part 22 is more than the first fluid ejection part 21 in plan view. May also be increased. In addition, when the upper surface of the second porous member (that is, the surface on the substrate side) can be formed with high accuracy, such as when the substrate to be supported is relatively small, the second porous member is the same as the lower surface of the substrate. The second fluid may be uniformly ejected from the second porous member toward the entire lower surface of the substrate. In this case, only the first fluid ejection part 21 is moved relative to the substrate by the ejection part moving mechanism 25.

  In the substrate measuring apparatus 1 according to the first embodiment, measurement of CV characteristics may be performed on a semiconductor substrate (so-called bare wafer) in which an insulating film is not formed on the upper surface 91 and the lower surface 92. Similarly, in the substrate measuring apparatuses according to the third and fourth embodiments, the surface potential may be measured for a semiconductor substrate in which no insulating film is formed on the upper surface 91.

  In the substrate measuring apparatus according to the first to third embodiments, the second porous member 221 may be formed of a porous material having semiconductivity. In the substrate measuring apparatus according to the third and fourth embodiments, a minute current output from the measurement electrode 31 to the processing unit 57 is used as a displacement current, and based on the displacement current and the electrode potential of the measurement electrode 31. The surface potential in the target region 911 may be obtained. Further, the substrate measuring apparatus according to the third and fourth embodiments is provided with an ellipsometer provided in the substrate measuring apparatus 1a according to the second embodiment. It may be used when a relationship with change is obtained.

  In the substrate measuring apparatus according to the above-described embodiment, the CV characteristics and the surface potential in the target region 911 do not necessarily need to be measured, and other various electrical characteristics of the substrate 9 in the target region 911 are from the measurement unit 3. The calculation unit may acquire the output based on the output. Even in this case, as in the above-described embodiment, the substrate 9 is supported while being flattened, and the measuring unit 3 can be easily and quickly moved to the substrate 9 to a position where it is difficult to bring the substrate 9 close only by the control of the first fluid. Thus, highly accurate measurement of electrical characteristics can be realized. In addition, the measurement of electrical characteristics can be speeded up. Furthermore, the substrate measuring apparatus may be used for measurement of predetermined characteristics other than the electrical characteristics in the target area 911 (for example, defect inspection of the target area 911).

  In the substrate measuring apparatus, the first fluid and the second fluid ejected from the first porous member 211 and the second porous member 221 are not necessarily limited to gases and do not affect the measurement of the characteristics of the substrate 9. For example, a liquid having a relatively low viscosity such as pure water may be used.

  The substrate measuring apparatus may be used for measuring the characteristics of a glass substrate for a flat display device such as a liquid crystal display device or a plasma display device in addition to a semiconductor substrate, and other substrates (for example, You may utilize for the characteristic measurement of the plastic substrate in which the thin film of the organic semiconductor was formed (or the plastic substrate used for a solar cell).

1 is a plan view of a substrate measuring apparatus according to a first embodiment of the present invention. It is a longitudinal cross-sectional view of a board | substrate measuring apparatus. It is a longitudinal cross-sectional view of a board | substrate measuring apparatus. It is a longitudinal cross-sectional view which expands and shows the site | part of a measurement part vicinity. It is a figure which shows the flow of a measurement of a CV characteristic. It is a longitudinal cross-sectional view which shows a part of board | substrate measuring apparatus based on the 2nd Embodiment of this invention. It is a longitudinal cross-sectional view which shows a part of board | substrate measuring apparatus based on the 3rd Embodiment of this invention. It is a figure which shows the flow of surface potential measurement. It is a longitudinal cross-sectional view which shows a part of board | substrate measuring apparatus based on the 4th Embodiment of this invention.

Explanation of symbols

1, 1a to 1c Substrate measuring apparatus 3 Measuring unit 4 Measuring unit moving mechanism 9 Substrate 21 First fluid ejecting unit 22 Second fluid ejecting unit 24 Substrate rotating mechanism 25 Ejecting unit moving mechanism 31 Measuring electrode 32 Electrode holding unit 33 Light source unit 34 Light receiving unit 35 Film thickness calculating unit 41 Piezoelectric element 42 Air bearing 51 Voltage applying unit 52 Capacitance meter 53 Characteristic calculating unit 55 Potential applying unit 56 Surface potential calculating unit 61 Auxiliary electrode 62 Air cylinder 91 Upper surface 92 Lower surface 93 Outer edge 211 First porous Material member 212 first support block 221 second porous member 225 switching mechanism 231 movement restriction portion 232 auxiliary support portion 421 guide portion 911 target region S11 to S18, S21 to S28 Steps

Claims (16)

A substrate measuring apparatus for measuring a predetermined characteristic in a target region of a substrate,
A first fluid ejecting portion that ejects the first fluid from the first porous member toward the periphery of the target region on one main surface of the substrate;
The first porous member and the second porous member are disposed so as to face the first fluid ejecting portion and eject the second fluid from the second porous member toward the other main surface of the substrate. A second fluid ejection portion that supports the substrate in a non-contact manner with a member;
A movement restricting portion that abuts on an outer edge portion of the substrate and restricts movement in a direction parallel to the one main surface of the substrate;
A target region changing mechanism that changes the target region by moving the first fluid ejection portion relative to the substrate along the one main surface of the substrate;
A measurement unit attached to the first fluid ejection unit and facing the target region of the substrate;
When the measurement unit measures a predetermined characteristic of the target region, the measurement unit is moved relative to the first fluid ejection unit in a direction toward the one main surface of the substrate. A measuring part moving mechanism that is brought close to the main surface of the non-contacting,
A substrate measuring apparatus comprising: The substrate measuring apparatus according to claim 1,
The measurement unit moves closer to the one main surface until the distance between the tip of the measurement unit and the one main surface of the substrate is less than 5 μm by the measurement unit moving mechanism. Substrate measuring device. It is a board | substrate measuring apparatus of Claim 1 or 2, Comprising:
The second fluid ejection part ejects the second fluid toward a part of the other main surface of the substrate, and moves relative to the substrate together with the first fluid ejection part. Substrate measuring device. It is a board | substrate measuring apparatus of Claim 3, Comprising:
The substrate measuring apparatus, wherein the first porous member and the second porous member have the same shape and overlap in a direction perpendicular to the substrate. The substrate measuring apparatus according to claim 3 or 4, wherein
The first fluid and the second fluid are gases;
The substrate is a semiconductor substrate;
The second porous member is formed of a conductive or semiconductive material;
The substrate measuring apparatus is
A voltage application unit that applies a voltage to the measurement electrode facing the target region of the measurement unit;
A capacity measuring unit for obtaining a combined capacity between the measurement electrode and the second porous member;
An arithmetic unit that obtains a relationship between the applied voltage and the combined capacitance in the target region based on an output from the capacitance measuring unit while changing an applied voltage applied to the measurement electrode;
A switching mechanism for switching supply of the second fluid to the second porous member of the second fluid ejection portion and suction of the fluid through the second porous member;
Further comprising
When the relationship is acquired, suction is performed through the second porous member by the switching mechanism, whereby the other main surface of the substrate is adsorbed to and electrically connected to the second porous member. And
When the second fluid ejecting portion moves relative to the substrate together with the first fluid ejecting portion by the target region changing mechanism, the second fluid from the second porous member is moved by the switching mechanism. A substrate measuring apparatus, wherein ejection is performed. It is a board | substrate measuring apparatus of Claim 5, Comprising:
The substrate is a semiconductor substrate having an insulating film formed on the one main surface;
The measurement unit is
A light source unit that makes light incident on the target area of the substrate;
A light receiving unit that receives reflected light from the target region of light from the light source unit;
A film thickness calculation unit for determining the thickness of the insulating film in the target region based on an output from the light receiving unit;
A substrate measuring apparatus comprising: The substrate measuring apparatus according to claim 3 or 4, wherein
The first fluid and the second fluid are gases;
The substrate is a semiconductor substrate having an insulating film formed on the other main surface;
The substrate measuring apparatus is
A potential applying unit that applies a potential to the measurement electrode facing the target region of the measurement unit;
An auxiliary electrode attached to the second fluid ejection part;
An auxiliary electrode moving mechanism that moves the auxiliary electrode relative to the second fluid ejection portion in a direction toward the other main surface of the substrate;
A vibrating section that vibrates the measurement electrode in a vibration direction toward the target region;
A calculation unit for obtaining a surface potential of the target region based on an electrode potential of the measurement electrode when the measurement electrode is vibrated and a displacement current from the measurement electrode or the auxiliary electrode;
Further comprising
When the surface potential is obtained, the auxiliary electrode is moved by the auxiliary electrode moving mechanism, and the tip of the auxiliary electrode comes into contact with the substrate main body of the substrate on the other main surface of the substrate. Electrically connected to the
When the second fluid ejection part moves relative to the substrate together with the first fluid ejection part by the target area changing mechanism, the auxiliary electrode is separated from the other main surface by the auxiliary electrode moving mechanism. The board | substrate measuring apparatus characterized by the above-mentioned. The substrate measuring apparatus according to claim 3 or 4, wherein
The first fluid and the second fluid are gases;
The substrate is a semiconductor substrate;
The second porous member is formed of a conductive or semiconductive material;
The substrate measuring apparatus is
A potential applying unit that applies a potential to the measurement electrode facing the target region of the measurement unit;
A vibrating section that vibrates the measurement electrode in a vibration direction toward the target region;
A calculation unit for obtaining a surface potential of the target region based on an electrode potential of the measurement electrode when the measurement electrode is vibrated and a displacement current from the measurement electrode or the second porous member;
A switching mechanism for switching supply of the second fluid to the second porous member of the second fluid ejection portion and suction of the fluid through the second porous member;
Further comprising
When the surface potential is determined, suction is performed through the second porous member by the switching mechanism, so that the other main surface of the substrate is adsorbed to and electrically connected to the second porous member. And
When the second fluid ejecting portion moves relative to the substrate together with the first fluid ejecting portion by the target region changing mechanism, the second fluid from the second porous member is moved by the switching mechanism. A substrate measuring apparatus, wherein ejection is performed. The substrate measuring apparatus according to any one of claims 1 to 4,
A calculation unit for calculating the output from the measurement unit;
The first fluid and the second fluid are gases;
The substrate is a semiconductor substrate;
The substrate measurement apparatus characterized in that an electric characteristic of the substrate in the target region is acquired by the arithmetic unit based on an output from the measurement unit. It is a board | substrate measuring apparatus in any one of Claim 1 thru | or 9, Comprising:
The substrate measuring apparatus, wherein the first porous member has an annular shape surrounding the target region. It is a board | substrate measuring apparatus of Claim 10, Comprising:
The substrate measuring apparatus, wherein the first porous member is annular. It is a board | substrate measuring device of Claim 10 or 11,
The substrate measuring apparatus, wherein the first fluid ejection portion includes a closing portion that closes a space inside the first porous member on a side opposite to the substrate of the first porous member. A substrate measuring apparatus according to any one of claims 10 to 12,
The substrate measuring apparatus, wherein a space between the measurement unit and the target region is an inert gas atmosphere or a reduced pressure atmosphere. The substrate measuring apparatus according to any one of claims 1 to 13,
The board | substrate measuring apparatus further provided with the auxiliary | assistant support part which supports the said board | substrate in the vicinity of the said outer edge part of the said board | substrate. The substrate measuring apparatus according to any one of claims 1 to 14,
The measuring unit moving mechanism ejects a supporting fluid toward a gap between a guiding unit fixed to the first fluid ejecting unit and a moving unit provided in the measuring unit; A substrate measuring apparatus comprising a linear motion guide mechanism for guiding the measuring unit while keeping the moving unit in a non-contact state. The substrate measuring apparatus according to any one of claims 1 to 15,
The substrate measuring apparatus, wherein the measuring unit moving mechanism includes a piezoelectric element that moves the measuring unit by expanding and contracting in the moving direction of the measuring unit.

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