JP5779449B2 - Combined measuring device for measuring resistance and displacement - Google Patents

Description

  The present invention relates to a technique for measuring a surface shape of a thin film and a resistance measurement.

  From the prior art, dedicated measurement devices are used for measuring the surface roughness of the substrate and measuring the resistance of the substrate. First, the substrate is placed on the mounting table of one of the measurement devices, and then measured. Is measured on a mounting table of another measuring apparatus. Thus, since the resistance value and the displacement of the surface were measured with separate devices, it was necessary to move between the substrate mounting tables and to replace the jig, especially when the substrate to be measured was large, There was a problem that the installation area became large.

If a substrate is placed on a high resistance mounting plate such as Teflon (registered trademark) in order to measure the surface shape and low resistance measurement with a single mounting table, the resistance is accurately measured. Since the flatness of the mounting plate is poor, there is a problem that the accuracy of displacement measurement for obtaining the surface irregularities is poor.
On the other hand, the chuck on which the substrate for measuring the surface shape is placed has low insulation, and the measurement accuracy of the resistance value of the high resistance thin film deteriorates on this chuck.

JP 05-045389 A JP 2009-133730 A

  The present invention was created to solve the above-described disadvantages of the prior art, and an object of the present invention is to provide a measuring apparatus that can accurately measure the surface shape and resistance of a substrate.

In order to solve the above-described problems, the present invention provides a high-resistance placement plate that is horizontally disposed on a placement surface that is a surface of a measurement target substrate, and a placement plate that is disposed above the placement plate. A probe is brought into contact with the surface of the substrate on the plate, and a resistance measuring device that detects a current by applying a voltage to the probe is disposed above the mounting plate, and touches the surface of the substrate on the mounting plate. A surface shape measuring device that moves the stylus in contact with the tip of the needle and detects the amount of displacement of the stylus in the vertical direction, the resistance measuring device, and the surface shape measuring device, A moving device that moves the mounting plate parallel to the mounting plate; and first and second lifting devices that move the probe and the stylus in the vertical direction, respectively, and the probe and the stylus is configured to allow separated from contact with the substrate surface, the mounting plate is Mounting surface is machined to be flat, the probe has a first, second electrodes, on the back surface of the mounting plate, is arranged a guard electrode in contact with the mounting plate, the power supply potential difference first can be formed, of the second terminal, wherein the first terminal, said the first electrode is connected, wherein the second terminal, the guard electrode is connected, the second electrode Is a composite measuring device connected to the second terminal via an ammeter.
Moreover, this invention is a composite measuring apparatus with which the said mounting plate was comprised with the polyacetal resin.

According to the present invention, since the current flowing in the thickness direction of the mounting plate does not flow through the ammeter, accurate resistance measurement can be performed.
Since the mounting plate of the present invention is made of resin and the surface is processed to be flat, steps, irregularities, and undulations on the substrate surface can be accurately measured.
In addition, the measurement is simple because it is not necessary to replace a jig or the like for the measurement.

(A): The figure which looked at the measuring device of the present invention from the perpendicular upper part. (A): Circuit diagram of resistance measuring device (b): A diagram for explaining a state in which an annular electrode and a disk electrode are in contact with the substrate surface The figure for explaining the measurement procedure with the surface shape measuring device

Reference numeral 2 in FIGS. 1A and 1B shows the composite measuring apparatus of the present invention.
FIG. 1A shows a view of the composite measurement apparatus 2 as viewed from above, and FIG. 1B shows a view of the composite measurement apparatus 2 seen from the side.

This composite measuring apparatus 2 has a mounting table 11, and is arranged on the surface of the mounting table 11 so that two rails 13 are positioned in parallel in a horizontal plane.
On the rail 13, an elongated attachment plate 15 is arranged so that its longitudinal direction is perpendicular to the rail 13 and is located in a horizontal plane.

  A first fixed magnet portion 14 in which a plurality of electromagnets are arranged along the direction in which the rail 13 extends is disposed on the side surface of the rail 13, and a permanent magnet is provided on the mounting plate 15 at a position close to the electromagnet. The first moving magnet unit 16 is arranged, and the first fixed magnet unit 14 and the first moving magnet unit 16 constitute a first linear motor 17.

  A control device 19 and a power source 21 are arranged outside the mounting table 11, and the first linear motor 17 is controlled by the control device 19, and an electromagnet is placed at a desired position of the first fixed magnet unit 14. The mounting plate 15 to which the first moving magnet unit 16 is fixed by the force applied to the first moving magnet unit 16 by the electromagnetic force between the first moving magnet unit 16 and the rail 13 is formed. It moves in a desired direction along.

  The second fixed magnet portion 22 of the second linear motor 27 is also provided on the side surface of the mounting plate 15 so as to be positioned in the horizontal plane. The resistance measuring device 40 and the surface shape measuring device are provided on the mounting plate 15. 60 is provided to be movable along the second fixed magnet portion 22.

  The resistance measuring device 40 and the surface shape measuring device 60 are provided with a second moving magnet portion 42 made of a permanent magnet and formed between the second fixed magnet portion 22 and the second moving magnet portion 42. A force is applied to the second moving magnet unit 42 by the electromagnetic force, and the resistance measuring device 40 and the surface shape measuring device 60 are configured to move in the desired direction along the second fixed magnet unit 22. Yes.

In the portion between the rails 13 on the surface of the mounting table 11, a mounting plate 12 made of a resin plate is horizontally disposed, and the mounting surface which is the surface of the mounting plate 12 is uneven or wavy. Molded on a flat surface.
The portion of the mounting table 11 on which the mounting plate 12 is placed is an aluminum plate 56 so that the flatness and parallelism of the surface of the mounting plate 12 are improved.

  The mounting plate 12 and a portion of the aluminum plate 56 of the mounting table 11 on which the mounting plate 12 is disposed are provided with suction ports (not shown) penetrating in the thickness direction. The suction port is connected to the vacuum pump 29. When the substrate is placed on the mounting plate 12 and the vacuum pump 29 is operated, the suction port is evacuated and the substrate is pressed against the mounting plate 12 by atmospheric pressure. As a result, the undulation of the substrate is eliminated. As a result, the surface of the substrate is flattened and the surface of the substrate is horizontal.

Reference numeral 23 in FIG. 1 indicates a substrate disposed on the mounting plate 12 of the mounting table 11.
The surface shape measuring device 60 has a stylus 63 whose tip is directed downward, and a displacement meter 65 for bringing the stylus 63 into contact with a measurement object at a desired pressure and measuring the amount of movement of the stylus 63 in the vertical vertical direction. And have.
The resistance measurement device 40 includes a probe 41 and a measurement circuit 53. The measurement circuit 53 includes a probe power supply 45 that applies a voltage to the probe 41 and an ammeter 47 that measures current.

  The probe 41 includes an annular electrode 43 made of an annular flat conductor, and a disk-shaped disc electrode 44 disposed inside the annular electrode 43. The inner circumference and outer circumference of the annular electrode 43 and the outer circumference of the disc electrode 44 are circular, the width of the annular electrode 43 is constant, and the center of the annular electrode 43 and the center of the disc electrode 44 are identical to each other. It is arranged in a plane. Even when the probe 41 moves, the annular electrode 43 and the disc electrode 44 are fixed to each other so that a constant distance is maintained between the outer circumference of the disc electrode 44 and the inner circumference of the annular electrode 43. Yes.

The measurement circuit 53 is shown in FIG.
The probe power supply 45 has a positive voltage terminal 46 and a negative voltage terminal 48.
The positive voltage terminal 46 is connected to the annular electrode 43, and the disk electrode 44 is connected to the negative voltage terminal 48 via the ammeter 47.
An aluminum plate 56 disposed on the back surface of the mounting plate 12 serves as a guard electrode 52 and is connected to the negative voltage terminal 48.

  The substrate 23 to be measured has a high resistance layer 25 made of an oxide semiconductor or the like formed on the surface of a support plate 24 made of an insulating material such as glass. The one side of the disk electrode 44 of the probe 41 and the ring electrode 43 When one surface on the same side as the disk electrode 44 is brought into contact with the high resistance layer 25 of the substrate 23 and a voltage is applied between the annular electrode 43 and the disk electrode 44, the current flowing through the high resistance layer 25 is supplied to the ammeter 47. Also flows.

  On the other hand, even if the negative voltage terminal 48 is connected to the ground potential, the current flowing between the annular electrode 43 and the guard electrode 52 does not flow through the ammeter 47. The measurement result of 47 is not affected, and a measurement error due to a leak current flowing in the thickness direction of the substrate 23 does not occur.

  FIG. 2B is a view for explaining a state in which the disc electrode 44 and the annular electrode 43 are in contact with the surface of the substrate 23. The inner and outer diameters of the annular electrode 43, the disc The diameter of the electrode 44 is input to the control device 19 in advance, and when the current value and the applied voltage value measured by the ammeter 47 are transmitted to the control device 19, the control device 19 receives the input current value. The storage device 10 arranged in the control device 19 calculates the resistance value in the thin film spreading direction of the high resistance layer 25 on the surface of the substrate 23 from the applied voltage value, and the stored contents relating to the annular electrode 43 and the disc electrode 44. To remember. Further, it is displayed on the display panel 9 of the control device 19.

  The resistance measuring device 40 and the surface shape measuring device 60 are moved to the true position of the desired position on the surface of the substrate 23 arranged on the mounting plate 12 by the moving device 20 including the first and second linear motors 17 and 27. Can be placed on top.

  The resistance measuring device 40 and the surface shape measuring device 60 have first and second lifting and lowering devices 49 and 67 for moving the resistance measuring device 40 and the surface shape measuring device 60 in the vertical direction, respectively. 41 and the stylus 63 are configured to move up and down on a desired position of the substrate 23.

Next, the surface shape measuring device 60 will be described.
The stylus 63 of the surface shape measuring device 60 moves between the starting point and the ending point on the surface of the substrate 23 while being in contact with the surface of the substrate 23, and measures the unevenness, step and undulation between the starting point and the ending point. Can do.

  When measuring, first, the substrate 23 is vacuum-sucked to eliminate the undulation, then the probe 41 and the stylus 63 are moved upward, and the probe 41 and the stylus 63 are separated from the surface of the substrate 23. Then, the resistance measuring device 40 and the surface shape measuring device 60 are moved right above the starting point of the substrate 23.

Then, the second lifting device 67 is operated, the surface shape measuring device 60 is arranged on the starting point, the stylus 63 is moved downward by the second lifting device 67, and the tip of the stylus 63 is brought into contact with the starting point. Let
A movement axis is provided inside the surface shape measuring device 60, and the stylus 63 is linearly and rotationally moved toward the end point by several centimeters by the movement axis. The tip of the stylus 63 is in contact with the surface of the substrate 23 until reaching the end point from the start point.

  During the movement, the stylus 63 is kept in contact with the surface of the substrate 23, and is moved up and down according to the unevenness of the surface of the substrate 23. The vertical movement of the stylus 63 is detected by the displacement meter 65, and a signal indicating the value. Are transmitted to the control device 19 at a predetermined cycle.

The control device 19 obtains a displacement amount that is a vertical movement amount of the stylus 63 from the input signal, and stores the time when the displacement amount is detected and the position of the stylus 63 together with the displacement amount. Then, the obtained displacement amount is displayed on the display panel 9 of the control device 19 in association with the position of the stylus 63.
For example, when the distance between the start point and the stylus 63 is set on the horizontal axis and the amount of displacement of the position of the stylus 63 in the vertical direction is set on the vertical axis, the change in the height of the surface of the substrate 23 between the start point and the end point can be known.

  A plurality of resistance measurement positions and surface shape measurement positions to be measured on the surface of the substrate 23 are respectively input to the control device 19. First, the first and second lifting devices 49 and 67 are connected to the resistance measurement device 40. The surface shape measuring device 60 is moved upward, and the resistance measuring device 40 and the surface shape measuring device 60 are measured by the moving device 20 in a state where the probe 41 and the stylus 63 are separated from the surface of the substrate 23. Move to the first resistance measurement position.

The first lifting / lowering device 49 lowers the probe 41 at the first resistance measurement position and brings the probe 41 into contact with the high resistance layer 25 on the surface of the substrate 23.
In this state, the resistance measuring device 40 places the guard electrode 52 at the ground potential, applies a voltage between the annular electrode 43 and the disk electrode 44, measures the current flowing through the ammeter 47, and sets the measured value as the resistance. The measurement device 40 outputs the resistance value to the control device 19, and the control device 19 obtains the resistance value and stores the value in association with the position. Then, the first lifting device 49 moves the probe 41 to the high resistance layer 25 on the surface of the substrate 23. Separate from.

Next, the resistance measuring device 40 and the surface shape measuring device 60 are moved by the moving device 20 to the second resistance measuring position to be measured in a state of being separated from the surface of the substrate 23, and the first resistance measuring position is moved. Measure the resistance in the same way as
After that, similarly to the first resistance measurement position, the resistance value is measured at the remaining resistance measurement positions to be measured input to the control device 19 on the surface of the substrate 23.

  When all the resistance measurement at the resistance measurement position to be measured input to the control device 19 is completed, the resistance measurement device 40 and the surface shape measurement device 60 are separated from the surface of the substrate 23 by the probe 41 and the stylus 63. In this state, the moving device 20 moves the first surface shape measurement position to be measured.

  Next, the second lifting / lowering device 67 moves the stylus 63 down, brings the stylus 63 into contact with the position to be the starting point on the surface of the substrate 23, and moves it by the moving device 20 while making contact with the end point. While moving from the start point to the end point, the surface shape measuring device 60 outputs a signal indicating the vertical displacement of the surface of the substrate 23 to the control device 19 in association with the position on the surface of the substrate 23. The displacement amount is stored together with the position on the substrate 23, and the stylus 63 is separated from the surface of the substrate 23.

Next, the moving device 20 moves the resistance measuring device 40 and the surface shape measuring device 60 to the second surface shape measuring position while being separated from the surface of the substrate 23, and Similarly, the amount of displacement is measured.
After that, similarly to the first surface shape measurement position, the displacement amount is measured at the remaining surface shape measurement positions to be measured, which are input to the control device 19 on the surface of the substrate 23.

  Here, after all the resistance values were measured at the resistance measurement positions to be measured, all the displacement amounts were measured at the surface shape measurement positions to be measured. After the amount measurement is completed, the resistance value may be measured at the resistance measurement position to be measured.

The resistance value of the oxide semiconductor thin film measured by the resistance measuring device 40 is about 1.00 × 10 ^{4 to} 9.99 × 10 ¹⁵ Ω, and the resistance measuring device 40 is provided with a low resistance probe 51. Thus, the low resistance of about 1.00 × 10 ^{−3 to} 5.00 × 10 ⁶ Ω can be measured by bringing the low resistance probe 51 into contact and passing a current through the thin film on the substrate surface.

  As described above, when the measurement point stored in the control device 19 is measured, the vacuum suction is released, the substrate 23 is moved from the mounting table 11, another substrate 23 to be measured is placed on the mounting table 11, and the vacuum In the adsorbed state, the resistance value and the displacement amount are measured.

As described above, in the present invention, since the resistance value and the displacement amount can be measured without moving the large substrate 23, the measurement is easy and the space is saved.
The plate as the mounting plate 12 of the present invention is a polyacetal resin, such as Delrin (registered trademark of DuPont Co., Ltd .: polytriacetal resin), Duracon (registered trademark of Polyplastic Co., Ltd.), Tenac (Asahi Kasei Corporation). When a high-resistance resin such as a fluorine resin is molded and used, the current flowing through the guard electrode 52 is reduced and the measurement accuracy is improved.

  In addition, since the surface of these resins can be flattened, the measurement accuracy of the displacement measurement is improved. Here, the mounting plate 12 is made of Delrin, and the flatness is 100 μm. The flatness of the aluminum plate 56 on which the mounting plate 12 is arranged is also 100 μm.

  In the above embodiment, the probe 41 and the stylus 63 are moved in the vertical direction by moving the resistance measuring device 40 and the surface shape measuring device 60 up and down, but the probe 41 may be moved or touched. The needle 63 and the displacement meter 65 may be moved together.

  The guard electrode 52 is not limited to the aluminum plate 56, and may be, for example, a metal thin film or a metal film formed on the back surface of the mounting plate 12. In that case, at least of the back surface of the mounting plate 12, The region directly behind the surface region surrounded by the outer periphery of the annular electrode 43 may be disposed in surface contact with the back surface of the mounting plate 12, but the back surface of the mounting plate 12 has no swell. It is desirable to arrange a plate having high flatness.

  Here, the guard electrode 52 is at least the same shape and the same size as the mounting plate 12, or is composed of an aluminum plate 56 larger than the mounting plate 12, and the entire back surface and the surface of the mounting plate 12. No matter which position on the surface of the substrate 23 is in contact with the probe 41, the current flowing in the thickness direction in the mounting plate 12 is prevented from flowing into the disk electrode 44 or the annular electrode 43. Yes.

  In the above embodiment, the negative voltage terminal 48 of the probe power supply 45 is grounded, and the ammeter 47 is inserted into the connection between the negative voltage terminal 48 and the disk electrode 44. If one of the electrodes is connected to the guard electrode 52 via the ammeter 47 and a voltage is applied between the other electrode and the guard electrode 52, the current flowing through the guard electrode 52 is changed to the ammeter 47. Does not flow.

In short, in the present invention, one of the annular electrode 43 and the disk electrode 44 is the first electrode, the other is the second electrode, and the second electrode is connected to the guard electrode 52 via the ammeter. It is only necessary that the resistance value is obtained by connecting the voltage value applied between the guard electrode 52 and the first electrode and the reading of the ammeter.
The annular electrode 43 and the disk electrode 44 are configured by forming a thin metal plate.

2 ... Measuring device 12 ... Mounting plate 20 ... Moving device 23 ... Substrate 40 ... Resistance measuring device 41 ... Probe 43 ... Ring electrode 44 ... Disc electrode 45 ... Probe power supply 47 ... Current Total 49 …… First lifting device 52 …… Guard electrode 60 …… Surface shape measuring device 63 …… Stylus 67 …… Second lifting device

Claims (2)

A high-resistance mounting plate disposed horizontally on a mounting surface on which the substrate to be measured is a surface;
A resistance measuring device disposed above the mounting plate, contacting a probe with the surface of the substrate on the mounting plate, and detecting a current by applying a voltage to the probe;
The tip of the stylus is placed above the mounting plate, the tip of the stylus is brought into contact with the surface of the substrate on the mounting plate, the stylus is moved in the contacted state, and the amount of vertical displacement of the stylus is determined. A surface shape measuring device to detect;
A moving device for moving the resistance measuring device and the surface shape measuring device in parallel with the mounting plate on the mounting plate;
First and second lifting and lowering devices that respectively move the probe and the stylus in the vertical direction, and the probe and the stylus are configured to be able to contact and separate from the substrate surface;
The mounting surface of the previous mounting plate is processed flat,
The probe has first and second electrodes,
The rear surface of the mounting plate, the guard electrode is disposed in contact with said mounting plate,
Of the first and second terminals where the power supply can form a potential difference,
The first electrode is connected to the first terminal,
Wherein the second terminal, the guard electrode is connected,
Said 2nd electrode is a compound measuring apparatus connected to said 2nd terminal via the ammeter.   The composite measuring apparatus according to claim 1, wherein the mounting plate is made of polyacetal resin.

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