JPH09246332A - Semiconductor chip measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor chip measuring method with which the electric characteristics of a semiconductor chip are measured by having a pad, formed on the semiconductor chip, and a probe to come in contact with each other at the prescribed probe pressure. SOLUTION: After the alignment of semiconductor wafers, where semiconductor chips are formed, a semiconductor chip C mounted stage is moved up. Then, when it is detected that all electrode pads P and probes are brought into contact with each other by a protective diode for every electrode pad P, or when the prescribed resistance value is obtained on the diffusion layer formed in the semiconductor chips C by the pads M1 to M4 for measurement of resistance of the diffusion layer sheet, two of which are provided adjacent to the four corners of the semiconductor chips C, the rising of the stage is stopped by judging that the pads and the probes are brought into contact with each other at the prescribed probe pressure, and the electric characteristics of the semiconductor chips are measured at the above-mentioned probe pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor chip measuring method for measuring the characteristics of a circuit mounted on a semiconductor chip in a semiconductor wafer state, and particularly to a pad and a probe formed on the semiconductor chip at the time of this measurement. It relates to the adjustment of the needle pressure with the needle.

[0002]

2. Description of the Related Art In the process of manufacturing a semiconductor chip, after a large number of chips having a predetermined circuit pattern are completed on a wafer, they are divided into individual chips and packaged. Electrical characteristics such as functional characteristics are inspected in a wafer state to eliminate defective chips. This is performed by the probe device 30 as shown in FIGS. 3 and 4, that is, the plurality of probe needles 42 (of the probe card 41) on the plurality of pads (not shown) in the chip C ′ formed on the wafer W. (Exaggerated in the figure), respectively, and the probe needle 42
Signals are exchanged between the tester 43 and the chip C'through the tester 43 to check whether the chip C'is a defective product. The wafer W is mounted on a stage 32 as shown in FIG. 4, and the stage 32 has a rotation mechanism 3 including a motor (not shown) for rotating the stage 32 about a vertical axis.
6, an elevating mechanism 35 for elevating (moving in the Z direction) a rotating mechanism 36 is provided below the X direction moving mechanism for moving the stage 32 in the X direction. 33 and a Y-direction moving mechanism 34 for moving in the Y-direction are provided. In addition, the probe card 41
Is attached to an insert ring 38 provided in an upper opening of a casing 37 that forms an exterior part of the probe device 30 main body, as shown in FIG.
Also, it is connected to the tester 43 via the test head 40. A microscope 45 is provided at the center of the test head 44 for visually observing the tip of the probe needle 42 and the like.

In this inspection, first, the X-direction moving mechanism 33,
By moving the Y-direction moving mechanism 34 and the rotating mechanism 36, the probe needles 42 of the probe card 41 and the pads formed on the wafer W are positioned so as to have a predetermined orientation on the same vertical, that is, the wafer W. To align. A technique for performing this alignment is disclosed in JP-A-6-
No. 232224, JP-A-6-124983 and JP-A-6-342833. JP 6
In Japanese Patent Laid-Open No. 232224, an image at a specific position taken in via a CCD device is compared with an image when a specific position is stored in a predetermined position, and an X stage and an image when these images match each other are detected. The amount of movement of the Y stage is obtained, and a motor for determining the position of the wafer is controlled according to the amount of movement to perform accurate alignment. In Japanese Patent Laid-Open No. 6-124983, for low magnification, the entire chip is projected. After adjusting the target chip with the lens, the four corners of the chip are enlarged with the high-magnification lens for accurate alignment. In addition, JP-A-6-3428
In Japanese Patent No. 33, a camera recognizes a target, which is a large mark having a predetermined positional relationship with a probe needle,
Since the actual probe needle should be near the calculated probe needle, the actual probe needle and the pad can be easily aligned, that is, the alignment can be easily performed.

For example, by the method disclosed in the above publication, after the pad on the wafer W and the probe needle 42 are positioned on the same vertical line, that is, after the alignment of the wafer W is completed, the operator does not press a button (not shown). The elevating mechanism 35 is raised by continuously pressing. As a result, the stage 32 on which the wafer W is placed gradually rises, the wafer W and the probe card 41 provided above the wafer W approach each other, and the pads and probe needles formed on the chip C ′ to be inspected 42 contacts. Furthermore, the probe needle 4
In order to ensure electrical contact between the two, the stage 32 on which the wafer W is mounted is raised (overdriven) by a predetermined amount, and then the rise of the stage 32 is stopped. At this time,
Due to insufficient needle pressure between the prober needle 42 and the pad, the contact resistance of the probe needle 42 increases and it becomes impossible to obtain a predetermined current, and even a good chip is a defective product in the DC characteristic test. It may be misunderstood. Therefore, as a technique for making electrical contact more reliable, for example, Japanese Patent Application Laid-Open No. 7-231017 discloses a height at which a probe needle comes into contact with a pad by a magnetic sensor provided on a mounting table on which a wafer is mounted. And a probe device for determining the needle pressure between the probe needle and the pad from the height so that a constant needle pressure can always be obtained, and JP-A-6-97243.
In the gazette, even if the probe needle that comes into contact with the heated wafer thermally expands and the stylus pressure between the pad and the probe needle changes with time, the stylus pressure between the probe needle and the wafer is first measured in terms of time. A probe device is disclosed which measures a change and adjusts the needle pressure between the probe needle and the pad based on the change.

Even when the probe card is mounted at an angle, the tip of the probe needle 42 does not uniformly contact the pad. As a technique for preventing this, for example, Japanese Patent Laid-Open No. 7-231018 discloses a probe. Based on the data obtained from the contact type displacement sensor for detecting the height of the needle tip of the needle, a technique for adjusting the inclination of the probe card by an inclination correction mechanism that supports the insert ring holding the probe card, In addition, JP-A-7-14254
Japanese Patent Publication No. 2 discloses a technique of detecting the depth of a probe needle by a change in current value due to contact resistance, and driving a tilt drive unit from the tilt of these probe needles to correct the tilt angle of a probe card.

[0006] Further, as a method for making the needle pressure of the probe needle and the pad to be a predetermined pressure, the probe needle 4
There is also a method of using a contact program that detects a contact failure between the pad 2 and the pad. This contact program
In order to prevent a high current from flowing inside the circuit of chip C'and destroying the inside of the circuit, the protection diodes connected to each pad are turned on (actually, a predetermined current is applied to the pad When it is a predetermined value, it is determined that the protection diode is ON (operating), and the pad and the probe needle 42 are in contact with each other with a small contact resistance, that is, each pad. When all the protection diodes provided for each are turned on, the tester determines that all pads are in contact with the probe needle with a predetermined needle pressure, that is, reliable electrical connection is made. It is a thing.

Next, a flow chart of stylus pressure adjustment using this contact program is shown in FIG. 5, which will be described below. First, the stage 32 on which the wafer W is placed
Are moved by the X-direction moving mechanism 33, the Y-direction moving mechanism 34, and the rotating mechanism 36 as described above, and the wafer W is aligned. When the alignment of the stage 32 is completed (indicated by S1 in the figure), then the lifting mechanism 3
5 is operated to raise the stage 32 (in the figure, S
2). Simultaneously with the rise of the stage 32, the contact program starts in the tester 42 (indicated by S3 in the figure). In the started contact program, it is determined whether all the protection diodes are turned on as described above (indicated by S4 in the figure), and when all the protection diodes are turned on, that is, all pads are turned on. When the tester determines that the probe needles have come into contact with each other with a predetermined needle pressure, the contact program ends (indicated by S5 in the figure), and the tester 42 raises the stage 32 on which the wafer W is mounted. A command to stop is issued, and the stage rise is stopped. Then, to the next work shown as S7 in the figure,
For example, operations such as setting terminals other than the measuring terminals to a specified condition for a DC characteristic test, and giving a test pattern to an input terminal for a functional test technique are performed.
In the figure, the broken line indicates the operation inside the tester 43.

However, in this contact program, the contact program is stopped only when all the protection diodes provided for each pad are turned on, that is, an instruction to end the rising of the stage 32 in this case is issued. No output. Therefore, if even one of the protection diodes is broken, the contact program does not end, and the stage 32 continues to rise without stopping. In this case, until now, the probe needle 42 has been bent as the stage 32 is moved upward via the microscope 45, or the tip C'because of the probe needle 42.
When it is possible to judge that the probe needle 42 of the probe card 41 is in contact with all the pads, the operator who is visually checking whether there is any damage to the stage 3
It had stopped climbing 2.

However, as the size of the chip C'is reduced, the size of the pad is also reduced, and it is becoming difficult to bring the needle tip into contact with the pad. In order to solve the problem, Japanese Patent Laid-Open No. 6-97243 discloses that a pad electrically connected to a pad formed on a chip and having a wider space than the pad is formed on a dicing line and then formed on the dicing line. A technique is disclosed in which a probe needle is brought into contact with a pad to inspect. However, in this publication, it is necessary to form a pad on the dicing line and to bond this pad with the pad on the chip, which increases the number of steps. In order to cope with the reduction in size without increasing the number of steps, the needle tip is made steep to suppress the amount of slip of the probe needle 42. In such a case, the probe needle 42
There is a problem that it becomes difficult to see the needle tip of.

That is, when the tip of the probe needle 42 becomes steep as the chip C ′ is reduced, the operator does not need to stop the rising of the stage 32 due to a failure of the protection diode. It becomes difficult to stop the rise of the stage 32 by confirming the above. Therefore, when the protection diode fails, the stage 32 continues to move upward, causing problems such as misalignment of the probe needle 42, bending of the probe needle 42, and damage to the chip C ′ itself. In addition, in order to prevent this, the operator needs to be extremely careful in adjusting the stylus pressure, which causes a problem that workability is deteriorated. Further, when the angle of the probe needle 42 becomes steeper, even if the operator observes it with the microscope 45, the needle tip of the probe needle 42 is hardly visible, and the needle pressure adjustment between the pad and the probe needle 42 is completely eliminated. It may not be possible.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a pad of a semiconductor chip and a probe needle are brought into contact with each other with a predetermined needle pressure, and due to insufficient needle pressure, a good chip is D
Prevents the C (DC characteristics) system from becoming defective, the prober needle to bend or misalign the needle due to excessive stylus pressure, and prevent damage to the circuit itself formed on the chip to perform a prescribed measurement. The present invention provides a method of measuring a semiconductor chip capable of performing

[0012]

SUMMARY OF THE INVENTION The above object is to provide a plurality of probe needles provided on a probe card and a plurality of pads so as to face the probe card after alignment of a semiconductor wafer on which semiconductor chips are formed is completed. When the tester connected to the probe needle determines that the semiconductor chip formed with the probe needle and the pad are brought into contact with each other at a predetermined needle pressure, the probe card and the semiconductor chip are moved closer to each other. And a method of measuring the electrical characteristics of the semiconductor chip in the shape of the semiconductor wafer by the tester, in the method of measuring the semiconductor chip, an electrode of the pad, which is connected to a circuit formed on the semiconductor chip. Detecting means for detecting contact between a pad and the probe needle for each electrode pad If all of the electrode pads are detected to be in contact with the probe needle, or the diffusion layer from the diffusion layer sheet resistance measurement pad connected to the diffusion layer in the semiconductor chip among the pads The semiconductor chip is characterized in that the tester determines that the probe needle and the pad are in contact with each other with the predetermined needle pressure when at least one of the cases where the predetermined sheet resistance value of the Is achieved by the measuring method.

By such a method, the stylus pressure between the probe needle provided on the probe card and the pad provided on the semiconductor chip is detected by the detecting means for each electric pad connected to the inside of the circuit of the semiconductor chip among the pads. When it is detected that the pad of is actually in contact with the probe needle, or the diffusion layer sheet resistance measuring pad connected to the diffusion layer in the semiconductor chip of the pad causes the diffusion layer to move through the probe needle. When the predetermined resistance value is obtained, the tester determines that the probe needle and the electrode pad are in contact with each other with a predetermined needle pressure, and stops the approaching between the probe card and the semiconductor chip. Since the distance between the probe needle and the pad is maintained at this time, the probe needle and the pad approach each other and the needle pressure becomes excessive, resulting in needle misalignment and needle bending. Circuits formed on the microcrystalline semiconductor chip or problem damage, also it is possible to prevent that the non-defective semiconductor chip by a needle pressure failure is mistaken as defective.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION In the method for measuring a semiconductor chip of the present invention, after aligning a wafer on which a semiconductor chip is formed, a detecting means for detecting contact between the electrode pad and the probe needle for each electrode pad. When it is detected that all the electrode pads and probe needles are in contact with, or the probe needles are used from the diffusion layer sheet resistance measurement pad for measuring the sheet resistance value of the diffusion layer provided inside the semiconductor chip. The approach between the semiconductor chip and the probe card is stopped when at least one of the states when a predetermined sheet resistance value of the diffusion layer is obtained is obtained. That is, it is determined by two different methods of detecting the actual contact for each electrode pad and measuring the sheet resistance of the diffusion layer whether the pad and the probe needle are in contact with each other with a predetermined needle pressure. for that reason,
Even if it is difficult for the operator to check the needle tip of the probe needle, and even if the detection means provided for each electrode pad fails, all electrode pads and probe needles can be reliably kept at the specified needle pressure. It can be judged that they are in contact, and the resistance value obtained from the diffusion layer sheet resistance measurement pad is much larger than the contact resistance, so it is clear that the sheet resistance is not the value obtained by the contact resistance. And
The probe needle and the electrode pad can be more reliably brought into contact with each other with a predetermined needle pressure. Therefore, the operator can visually check the needle tip of the probe needle without being overly cautious, even if the needle tip of the probe needle is difficult to see, thus improving workability.

Further, if the detection means for detecting that the probe needle and the electrode pad are in contact with each other with a predetermined needle pressure is performed by the diode formed in the semiconductor chip, a complicated detection means can be obtained. Even without providing, it is possible to easily know the contact for each electrode pad.

Also, most of the pads are electrode pads, and even if the inclination of the probe card and variations in the height of the probe needle itself are taken into consideration, it can be determined that all pads are in contact with the probe needle. By providing the diffusion layer sheet resistance measurement pad provided in, since the detection means for detecting the contact between the electrode pad and the probe needle is provided for each electrode pad connected to the circuit of the semiconductor chip, all Judging the actual contact state of the electrode pad,
Stop approaching the probe card and semiconductor chip,
The probe needle and the electrode pad can be brought into contact with each other with an actual predetermined needle pressure, and even if the inclination of the probe card and variations in the height of the probe needle itself are taken into consideration, all pads will come into contact with the probe needle. If all of the diffusion layer sheet resistance measurement pads provided at the locations and the number that can be determined to have a predetermined resistance value have a certain resistance value, even if the detection means that determines the actual contact state fails, the probe can be reliably used. It is possible to surely adjust the needle and the pad to a predetermined needle pressure, that is, a needle pressure that does not cause contact failure and does not cause bending or misalignment of the probe needle or damage to the semiconductor chip itself.

Further, if the probe card is fixed, the semiconductor wafer is placed on the stage, and the stage is raised so that the probe card and the semiconductor chip come close to each other, the semiconductor wafer can be easily installed. In addition, alignment of the semiconductor wafer can be performed relatively easily.

[0018]

FIG. 2 shows one of a plurality of semiconductor chips C formed on a semiconductor wafer used in an embodiment of the present invention. The semiconductor chip C is formed in a rectangular shape, and two diffusion layer sheet resistance measuring pads M1, M2, M3, M4 made of, for example, aluminum are provided adjacent to each other at four corners thereof. The diffusion layer sheet resistance measurement pads M1, M2, M3, and M4 are semiconductor chips C, respectively.
It is connected to a diffusion layer (not shown) formed inside and having a predetermined resistance value (this value varies depending on the ion species and dose amount at the time of formation), and each diffusion layer is connected via a probe needle of a probe card. Sheet resistance measurement pad M1
, M2, M3, M4 diffusion layer sheet resistance between
For example, the measurement is performed using a known 4-terminal method or 2-terminal method. Each diffusion layer sheet resistance measurement pad M1, M2,
For the resistance obtained from M3 and M4, each of the probe needles of the probe card has a diffusion layer sheet resistance measurement pad M1.
, M2, M3, and M4 have a predetermined needle pressure, that is, diffusion layer sheet resistance measurement pads M1, M2, M3, and M.
4 When the contact resistance between the probe needle and the probe needle is sufficiently small, and the probe needle is in contact with a needle pressure that does not bend, the specified resistance value (the specific value of this specified resistance value is It depends on the rating and device).

Further, in the semiconductor chip C, a plurality of electrode pads P are formed on the outer periphery of the semiconductor chip C. The electrode pad P is made of, for example, aluminum and is connected to a circuit formed in the semiconductor chip C, that is, formed as an external terminal of the circuit. Similar to the pad used in the conventional example, the electrode pad P is provided with a protection diode for preventing a high voltage from being applied to the electrode pad P to cause a high current to flow inside the circuit and destroy the inside of the circuit. There is. This protection diode is judged to be ON when a current flows from an unillustrated tester to the electrode pad via a probe needle and a predetermined voltage is obtained from the electrode pad. That is, when it is possible to determine that the protection diode is ON, the electrode pad provided with the protection diode has a predetermined needle pressure with the probe needle of the probe card, that is, a non-defective semiconductor chip is defective due to insufficient needle pressure. The tester determines that the contact is made with a stylus pressure that is not mistaken for.

FIG. 1 shows a method of measuring a semiconductor chip according to an embodiment of the present invention. First, a semiconductor wafer is aligned by using a known method as described in the above-mentioned conventional example, and a first step is performed. After completing the alignment of No. 1, the worker continues to push a button (not shown) to raise the semiconductor wafer as the second step 2. At the same time as the stage is raised, the contact program in the tester is started (this is shown in the third step 3 in the figure). In the contact program, all the protection diodes provided for each of the electrode pads P described above are ON, or the diffusion layer sheet resistance measurement pads M1, M2, M3, M4 provided at the corners described above are all turned on. , It is determined whether or not at least one of the predetermined resistance values is obtained (the fourth step 4 in the figure).
). If all the protection diodes are ON or if predetermined values are obtained from the diffusion layer sheet resistance measurement pads M1, M2, M3, M4 provided at the corners of the semiconductor chip C, the semiconductor chip C is The tester determines that the provided pads, that is, the electrode pads P and the diffusion layer sheet resistance measuring pads M1, M2, M3, and M4, and the probe needle are in contact with each other with a predetermined needle pressure, and the contact program is terminated (this is 5th step 5 in the figure
). Immediately after the contact program ends, as the sixth step 6, the ascending stage is stopped. When the stage is stopped, the needle pressures of the pads (the electrode pads P and the diffusion layer sheet resistance measuring pads M1, M2, M3, M4) and the probe needle are determined, and the next operation is performed as in the conventional example. (Shown in the seventh step 7 in the figure), for example, to set a terminal other than the measuring terminal to a specified condition for a DC characteristic test,
For example, in order to perform a functional test technique, the work of giving a test pattern to an input terminal is performed. In the figure, the broken line indicates that the process is performed in the tester.

In the present embodiment, not only the stop of rising of the stage is discriminated by the protection diode used in the conventional example, but also the diffusion layer sheet resistance measuring pads M1, M2, M3 provided at the four corners of the semiconductor chip C. , M4 has a predetermined resistance, the judgment criterion is that the protection diode in the semiconductor chip C is broken, so that all the pads are properly contacted by the needle, but the semiconductor chip The stage on which C is placed continues to climb,
Therefore, it is possible to prevent misalignment or bending of the probe needle, resulting in defects or circuit damage. Further, since the operator who raises the stage does not become overly careful in adjusting the stylus pressure, that is, the stylus pressure can be easily adjusted, workability is improved. Furthermore, even if the angle of the probe needle of the probe card becomes steeper as the semiconductor chip C is made smaller, that is, even if the operator cannot see the needle tip of the probe needle, the probe needle will not be visible at a predetermined needle pressure. The pads (electrode pads P and diffusion layer sheet resistance measurement pads M1, M2, M3, M4) can be brought into contact with each other.

Although the embodiments of the present invention have been described above, the present invention is, of course, not limited thereto, and various modifications can be made based on the technical concept of the present invention.

For example, in the above-described embodiment, the probe card provided with the probe needle is fixed above the semiconductor wafer, the stage on which the semiconductor wafer is mounted is raised, and the probe needle and the pad of the semiconductor chip C (electrode pad P and Although the diffusion layer sheet resistance measuring pads M1, M2, M3, M4) are brought into contact with each other, the semiconductor wafer may be fixed above by some means, for example, a suction chuck or the like, and the probe needle may be provided below. Alternatively, the semiconductor wafer may be fixed, the probe card may be brought closer to the semiconductor wafer, and the probe needle and the pad of the semiconductor chip may be brought into contact with each other. In the above-described embodiment, the contact program issues an instruction to stop the ascent of the stage on which the semiconductor wafer is placed, but in such a modification, the drive source for bringing the probe needle and the pad of the semiconductor chip into close proximity is stopped. To do so.

In the above embodiment, the semiconductor chip has a rectangular shape and two diffusion layer sheet resistance measurement pads M1, M2, M3 and M4 adjacent to the four corners are provided.
The position and the number of the diffusion layer sheet resistance measurement pads are not limited, and it is possible to determine that all the pads are in contact with the probe needles even in consideration of the inclination of the probe needle and the variation in the height of the probe needle itself. It suffices if there are such places and numbers. For example, if there is little variation in the probe needles, a pair of diffusion layer sheet resistance measurement pads for measuring the sheet resistance of the diffusion layer may be arranged at three positions that are not on the same line, and may be provided by, for example, three corners. If the height of the probe needle itself is large, for example, the number of pairs of diffusion layer sheet resistance measurement pads is increased to ensure that the pads formed on the semiconductor chip are aligned with the probe needle and the predetermined needle. It is possible to determine that they are in contact with each other by pressure.

In the above embodiment, the sheet resistance of the diffusion layer formed inside the semiconductor chip C between the two adjacent diffusion layer sheet resistance measurement pads M1, M2, M3 and M4 was measured. The predetermined sheet resistance of the diffusion layer may be measured by two of the diffusion layer sheet resistance measurement pads, for example, one of the diffusion layer sheet resistance measurement pads M1 and the diffusion layer sheet resistance measurement pad M.
A given sheet resistance may be measured by one of the two.
Further, the diffusion layer sheet resistance measuring pads may be provided not adjacent to each other.

[0026]

The present invention is embodied in the form described above and has the following effects.

In the present invention, after the alignment of the semiconductor wafer on which the semiconductor chip is formed is completed, the probe card provided with a plurality of probe needles and the semiconductor chip are brought close to each other, and the electrode pad and the probe are formed for each electrode pad formed on the semiconductor chip. When the detecting means for detecting the contact of the needle detects that all the electrode pads and the probe needle are in contact with each other with a predetermined needle pressure, or the diffusion layer sheet resistance connected to the diffusion layer in the semiconductor chip. When at least one of the case where a predetermined sheet resistance that the diffusion layer has from the measurement pad is obtained, the tester determines that each pad and the probe needle are in contact with each other with a predetermined needle pressure, Since the approach between the probe card and the semiconductor chip is stopped and the predetermined needle pressure is maintained to measure the electrical specification of the semiconductor chip, the detection means is destroyed. Even if the probe needle is not visible, or even if the tip of the probe needle becomes difficult to see, the probe needle and the pad can be reliably brought into contact with each other with a predetermined needle pressure, so that the probe needle is not misaligned or bent. , And it is possible to prevent problems such as damage to the semiconductor chip, and even if the chip is a good product due to insufficient stylus pressure, it is not mistaken for a defective product. Further, even if the operator who is looking at the needle tip of the probe needle does not easily see the needle tip, he does not have to be overly careful, so that workability is improved.

If most of the pads formed on the semiconductor chip are made of electrode pads, the detection means for detecting the actual contact between the electrode pad and the probe needle is provided for each electrode pad. Most of the pads can be detected by actual contact, and if the detection means breaks, all the pads will be probe needles even if the inclination of the probe card and variations in the height of the probe needle itself are taken into consideration. Since the diffusion layer sheet resistance measurement pads provided at the locations and the number of which can be discriminated to be in contact with the predetermined resistance value have been set, the probe needle and the pad can be more reliably connected to the predetermined needle pressure. It can be determined that they are in contact with each other.

[Brief description of drawings]

FIG. 1 is a flowchart for adjusting stylus pressure when measuring electrical characteristics of a semiconductor chip in a wafer state according to an embodiment of the present invention.

FIG. 2 is a diagram showing a position where an electrode pad, which is a pad of a semiconductor chip, and a diffusion layer sheet resistance measurement pad, which are measured in an embodiment of the present invention, are provided.

FIG. 3 is a front cross-sectional view of a probe device for explaining needle pressure adjustment between a probe needle and a pad formed on a semiconductor chip in order to measure electrical characteristics of a semiconductor chip in a conventional wafer state.

FIG. 4 is a perspective view showing a main part of the probe device of FIG.

FIG. 5 is a flowchart for adjusting a stylus pressure when measuring electrical characteristics of a semiconductor chip in a wafer state of a conventional example.

[Explanation of symbols]

1 ... 1st step, 2 ... 2nd step, 3 ... 3rd
Step 4 ... 4th step, 5 ... 5th step,
6 ... 6th step, 7 ... 7th step, C ... Semiconductor chip, M1, M2, M3, M4 ... Diffusion layer sheet resistance measuring pad, P ... Electrode pad.

Claims (5)

[Claims] 1. After alignment of a semiconductor wafer on which semiconductor chips are formed, a plurality of probe needles provided on a probe card and the semiconductor chip on which a plurality of pads are formed so as to face the probe card are provided. When the tester connected to the probe needle determines that the probe needle and the pad are brought into contact with each other at a predetermined needle pressure, the probe card and the semiconductor chip are stopped from approaching each other, and the tester In the method of measuring a semiconductor chip in which the electrical characteristics of the semiconductor chip are measured in the shape of a semiconductor wafer, an electrode pad of the pad, which is connected to a circuit formed on the semiconductor chip, and the probe needle are in contact with each other. That all of the electrode pads are When it is detected that it is in contact with the probe needle, or a predetermined sheet resistance value that the diffusion layer has from the diffusion layer sheet resistance measurement pad connected to the diffusion layer in the semiconductor chip among the pads In at least one of the above cases, the tester determines that the probe needle and the pad are in contact with each other with the predetermined needle pressure. 2. The method for measuring a semiconductor chip according to claim 1, wherein the detection means is a protection diode provided to prevent a high current from flowing inside the circuit to damage the circuit. 3. Most of the pads are the electrode pads, and all the pads are in contact with the probe needles even in consideration of the inclination of the probe card and the variation in height of the probe needles themselves. The method for measuring a semiconductor chip according to claim 1 or 2, wherein the diffusion layer sheet resistance measuring pads are provided in a number and a number of locations that can be determined to be. 4. The semiconductor chip is formed in a rectangular shape,
The method of measuring a semiconductor chip according to claim 3, wherein a pair of the diffusion layer sheet resistance measuring pads are formed adjacent to four corners of the semiconductor chip. 5. The semiconductor according to claim 1, wherein the probe card is fixed, and the stage on which the semiconductor wafer is mounted is raised to bring the probe card and the semiconductor chip closer to each other. How to measure chips.