JP2008028251A - Apparatus for inspecting semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for inspecting a semiconductor device which can suppress a voltage drop to a minimum, and can supply a correct voltage. <P>SOLUTION: The apparatus includes a wafer stage 1; a power supply device 3 for setting a potential of the wafer stage 1; a force line 4 for connecting the power supply device 3 to the wafer stage 1; a plurality of pins 5 serving as a sense disposed at a predetermined position of the wafer stage 1; a plurality of sense lines 6 connected to the plurality of pins 5, respectively; and a changeover switch 7 which is provided between the sense line 6 and the power supply device 3, selects one pin from the pins 5, and connects the sense line 6 corresponding to the selected pin 5 to the power supply device 3. A potential is controlled at a position of the selected pin 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a semiconductor device inspection apparatus, and more particularly to an improvement in an apparatus for controlling a potential on the back surface of a semiconductor wafer when a device is inspected.

  Conventionally, as in a power device, in order to control the potential of the back surface of a semiconductor wafer in which the back surface of the wafer is a common electrode of each chip, that is, the potential of the wafer stage, as shown in FIG. The connection point between the force terminal 22 and the sense terminal 23 of the power supply device 20 is connected to one point A at the end of the wafer stage 21, and the potential at the connection point given by the force terminal 22 is fed back from the sense terminal 23 to the power supply device 20. Thus, the power supply device 20 is controlled so that the potential applied by the force terminal 22 becomes a predetermined value.

  If this is shown as an electric circuit, it will become like FIG.5 (b). As shown in FIG. 5B, the power supply device 20 is a differential amplifier, for example, and is configured so that the potential at the connection point A can be arbitrarily adjusted.

  However, as the size of the semiconductor wafer increases, the wafer stage becomes larger. Therefore, every time the position of the device to be inspected (DUT point) is changed, the distance from the connection point to the device position of the inspection target (DUT point). Changes, and a voltage drop occurs due to the wiring resistance according to the distance from the connection point A to the DUT point. Therefore, there is a problem that the potential of the back surface of the semiconductor wafer at the DUT point when the device is inspected cannot be controlled accurately. It was.

  In order to solve the above-mentioned problems, the present invention detects a potential corresponding to the position of a device to be inspected and can accurately control the potential at that position to be a predetermined value. Is intended to provide.

A semiconductor device inspection apparatus according to the present invention includes a wafer stage, a power supply device for setting a potential of the wafer stage, a force line connecting the power supply device and the wafer stage, and a sense disposed at a predetermined position of the wafer stage. A plurality of pins, a plurality of sense lines connected to each of the plurality of pins, and provided between the sense line and the power supply device, selecting one of the pins and selecting A change-over switch for connecting the sense line corresponding to the pin to the power supply device is provided, and the potential at the position of the selected pin is controlled.

  In addition, it is preferable to provide a switching control device that performs the operation of the changeover switch by selecting the pin close to the inspection target with reference to the position information of the inspection target.

A semiconductor device inspection apparatus according to the present invention includes a wafer stage, a power supply device for setting a potential of the wafer stage, a force line connecting the power supply device and the wafer stage, and a sense disposed at a predetermined position of the wafer stage. A plurality of pins, a plurality of sense lines connected to each of the plurality of pins, and provided between the sense line and the power supply device, selecting one of the pins and selecting By providing a changeover switch for connecting the sense line corresponding to the pin to the power supply device, and by controlling the potential at the position of the selected pin, it is possible to correct the voltage drop, on the back surface of the semiconductor wafer The potential can be accurately controlled.

  In addition, by selecting a pin that is close to the inspection object by referring to the position information of the inspection object, and selecting the appropriate pin according to the progress of the inspection. Therefore, the voltage drop can be corrected more effectively, and the potential can be controlled more accurately.

The present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a semiconductor device inspection apparatus 1 according to the present invention.

  As shown in FIG. 1, a semiconductor device inspection apparatus 1 of the present invention includes a wafer stage 2 for setting a semiconductor wafer 10, a power supply device 3 for setting the potential of the wafer stage 2, the power supply device 3 and the A force line 4 that connects the wafer stage 2, a plurality of pins 5 that are arranged at predetermined positions on the wafer stage 2, a plurality of sense lines 6 that are respectively connected to the plurality of pins 5, and the sense line 6 And a selector switch 7 for selecting one pin 5 from the pins 5 and connecting the sense line 6 corresponding to the selected pin 5 to the power supply device 3. .

The wafer stage 2 is connected to the force line 4 to make a force as a whole. Then, one pin 5 close to the chip of the semiconductor device to be inspected is selected from the plurality of pins 5, and the sense line 6 connected to the pin 5 by the changeover switch 7 is connected to the power supply device 3, The one pin 5 is set as a sense. As a result, one force-sense connection point is generated on the back surface side (collector) of the semiconductor wafer 10, and the potential of the back surface of the semiconductor wafer is controlled.

A circuit diagram of the above configuration is shown in FIG. As shown in FIG. 3, the force-sense connection point 9 becomes a spot, and the force-sense connection point is switched by the changeover switch 7 according to the progress of the inspection. At this time, referring to the position information of the device to be inspected, appropriate switching is performed.

That is, in order to appropriately switch the force-sense connection point, the switching control device 8 is provided in the semiconductor device inspection device 1 of the present invention as shown in FIG. The switching control device 8 refers to the position information of the semiconductor device to be inspected, determines which pin 5 should be selected from the plurality of pins 5, and based on the result, switches the switch 7. Then, the connection is switched between the sense line 6 connected to the selected pin 5 and the power supply device 3.

The wafer stage 2 is a conductor and the pin 5 is also a conductor. However, the wafer stage 2 and the pin 5 are insulated from each other through an insulator and are arranged as shown in FIG. As the structure of the pin 5, a spring pin such as a pogo pin or a pin flush with the wafer stage 2 can be used.

It is preferable that the pins 5 are appropriately arranged according to the type of semiconductor device to be inspected. The pins 5 are arranged in accordance with the number of semiconductor devices and the arrangement state of the semiconductor device on the semiconductor wafer 10. Two pins are set as one area, a plurality of areas are set on the wafer stage, and one pin is provided in each area. It is possible to arrange pins one by one, or to arrange one pin in each area as one area with four chips.

Thus, in the past, all the devices on the semiconductor wafer 10 were handled with one sense, but for example, a plurality of areas such as one in two chips or one in four chips are arranged on the wafer stage. By setting, placing one pin 5 in each area, selecting the appropriate pin 5 and switching the connection with the power supply device 3 with the changeover switch 7, the force A sense connection point can be provided, and a setting error due to a voltage drop can be minimized. And it becomes possible to control an electric potential correctly.

  A system of the switching control device 8 and the changeover switch 7 in the semiconductor device inspection apparatus 1 of the present invention shown in FIG. 4 will be described. First, the switching control device 8 obtains position information (address X, Y) of a device to be inspected from a prober provided with a probe card 11 that inspects the semiconductor wafer 10. Then, the position table of the pin 5 previously input as data is referred to and compared with the position information of the device to be inspected.

As a result, it is determined which pin 5 is close to the device to be inspected from among the plurality of pins 5, and this is transmitted to the changeover switch 7 so as to switch to the sense line 6 connected to the selected pin 5. Then, the selector switch 7 switches the connection between the sense line 6 connected to the selected pin 5 and the power supply device 3.

By repeating the above-described process in accordance with the progress of the inspection and inspecting all the devices, it is possible to continuously provide a force-sense connection point at a position close to the device under inspection. Therefore, the wiring resistance between the semiconductor device and the force-sense connection point can be reduced, and voltage drop can be corrected. Therefore, appropriate potential control can be realized regardless of the position of the semiconductor device.

The schematic block diagram of the semiconductor device inspection apparatus of this invention. The top view of the wafer stage by which the some pin is arrange | positioned. 1 is a schematic circuit diagram of a semiconductor device inspection apparatus of the present invention. The system diagram of a change control device and a change switch. (A) is a schematic block diagram of the conventional semiconductor device inspection apparatus, (b) is an electric circuit diagram of the conventional semiconductor device inspection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor device inspection apparatus 2 Wafer stage 3 Power supply apparatus 4 Force line 5 Pin 6 Sense line 7 Changeover switch 8 Change control apparatus 9 Force sense connection point 10 Semiconductor wafer 11 Probe card 20 Power supply apparatus 21 Wafer stage 22 Force terminal 23 Sense terminal

Claims (2)

A wafer stage, a power supply device for setting the potential of the wafer stage, a force line connecting the power supply device and the wafer stage, a plurality of pins serving as senses arranged at predetermined positions of the wafer stage, the plurality of the plurality of pins A plurality of sense lines connected to each of the pins, and the sense line corresponding to the selected pin is selected between the sense line and the power supply device by selecting one of the pins A semiconductor device inspection apparatus comprising a changeover switch for connecting a power supply device to the power supply device, and controlling a potential at a position of the selected pin. The semiconductor device inspection apparatus according to claim 1, further comprising: a switching control device that performs an operation of the changeover switch by selecting the pin close to the inspection target with reference to position information of the inspection target.

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