JPH01235345A - Semiconductor inspection apparatus - Google Patents

Abstract

PURPOSE:To make a test head lightweight and small-sized and to enhance the operation performance of an inspection apparatus by a method wherein a comparator part of a pin electronics part is situated near a device under test and a driver part is arranged and installed at the outside of a measuring area of the device under test. CONSTITUTION:Only a peripheral circuit board and a comparator part CM out of a pin electronics part PE are built in a test head 2. A driver part DR used to give a voltage, timing and the like to a device under test in accordance with a test program by a control signal is arranged in the half way part of a connection cable between a tester 3 and the test head 2 at the outside of the test head 2. An amplifier PA is installed near a semiconductor wafer 5 between a semiconductor device on the semiconductor wafer 5 and the comparator part CM in order to match an impedance with a circuit and to stabilize measurements.

Description

[Detailed Description of the Invention] Highlights (Industrial Application Field) The present invention relates to semiconductor devices and integrated circuits completed on semiconductor wafers.
Regarding testing and inspection equipment used for characteristic testing of C (integrated circuits), LSI (large scale integrated circuits), etc., in particular, the stylus (probe) of a probe card is used to check whether these devices under test are good or bad, and whether they are electrical. It relates to equipment for testing and inspecting properties.

(Prior Art) Conventionally, for example, an inspection and measurement device (wafer prober) for semiconductor devices completed on a semiconductor wafer using contact needles of a probe card is shown in FIGS. 3 and 4 (A) and (B). The test head 31, which has a built-in pin electronics section PE consisting of a driver section DR and a comparator section CM, and a peripheral circuit board, etc., is separated from the tester 32 and placed directly on the wafer prober 33, and the wafer 34 to be measured is placed directly on the wafer prober 33. The device DUT and the pin electronics part PE built in the test head 31 are electrically connected by a bidirectional probe contact pin 39 provided between a probe card 36 having a probe 35 and a performance port 37, The tester 32 and the pin electronics section PE are connected by a connecting cable or the like. In addition, Figure 4 (
A) In (B), 37 is the pin electronics section P
38 is a frog ring in which a large number of bidirectional probe contact pins 39 are embedded and connects the probe card 36 and the performance port 37; 4o is an insert ring to which the probe card 36 is attached; 41 is a ring spacer. In this device, the pin electronics section PE
As shown in Fig. 5, IC-LSI etc. on a wafer (
(device under test) A driver section DR that applies voltage and timing according to the test program to the DUT, and a comparator section CM that is an output judgment circuit that compares whether the output from the device under test DUT is "1" or rQJ. It shortens the wiring length and prevents waveform distortion due to impedance mismatch, faithfully reproduces the waveform measured by the probe 35 of the probe card 36 on the device under test DUT, and performs high-speed testing. In order to achieve this, the pin electronics section PE is built into the movable test head 31 as described above, and during inspection, the pin electronics section PE is moved together with the test head 31 and placed at a position close to and above the probe card 36 for inspection. There is.

The inspection apparatus shown in FIG. 6 was adopted before the above-mentioned conventional technology, and as shown in the figure, a pin electronics section PE is built into the tester 32, and a wafer prober 33 and a pin electronics section PE are built into the tester 32. They are electrically connected by a long connection cable using a cable connector 42 or the like.

(Technical problem to be solved by the invention) However,
As shown in FIGS. 3 to 5, when the pin electronics section PE consisting of the driver section DR and the comparator section CM is built into the test head 31 that moves to a position near the probe card 36 during inspection, the test head 31 The weight and size of the test head 31 increases, deterioration of operability, occurrence of abnormal vibration when moving the test head 31,
Problems such as increased burden on the moving mechanism arise. Moreover, in recent years L
The measurement peripheral circuit board in the test head 31 has increased due to the increase in the number of radial probes 35 due to the high integration of SI etc., the increase in the number of external terminal pins, and the demand for high-speed testing of semiconductor devices at the semiconductor wafer stage. has also become more complex and
As the test head section 31 becomes larger and the weight of the test head section 31 including the pin electronics section PE tends to increase more and more, it has become difficult to deal with this. Further, this problem occurs not only in wafer probers but also in IC handlers.

In addition, as shown in FIG. 6, the pin electronics section P
If E is built into the tester 32 and the two are connected via a long cable from a distant wafer prober 33, test accuracy will deteriorate due to waveform delay and waveform distortion due to impedance mismatch between cable connections. This reduces the inspection speed and makes it impossible to meet the current standards of inspection accuracy and speed.

The present invention was invented in view of the above-mentioned conventional technical deficiencies, and its purpose is to solve the technical problem of unavoidable weight increase and enlargement of test heads including pin electronics parts in recent inspection equipment. It is an object of the present invention to provide a semiconductor testing device which solves the problems and reduces the weight and size of a test head, thereby preventing various disadvantages of the conventional technology, and without reducing testing accuracy.

Structure of the Invention (Means for Solving the Problems) In order to solve the above problems, the present invention employs the following structure.

In other words, the comparator section of the pin electronics section, which transmits and receives measurement signals between the tester and the probe card, is located near the device under test in a testing and inspection apparatus for semiconductor devices under test. The driver section was placed outside the measurement area of the device under test.

Further, the measurement signal from the device under test is input to the comparator section via an amplifier placed near the device under test.

(Function) According to the present invention as described above, since the test head does not have a built-in driver section having a considerable perspective, the test head is made lighter and smaller, and the operability of the inspection apparatus is significantly improved. By reducing the weight of this test head, it is sufficient to use a small rotating mechanism part of the inspection device. In addition, since the heat generated by the driver part has no effect on the device under test, there is no need for a cooling fan inside the test head, making it even smaller and lighter.Furthermore, the vibration of the fan can damage the wafer when the prober probe touches it. , there will be no wafer quality defects due to the influence of dust falling from the fan.

By being smaller and lighter in this way, the distance between the device under test and the comparator section can be further shortened, and the signal measured by the probe can be observed from the outside immediately at the time of measurement and the probe can be operated. It is also possible to improve sex. In addition, in the external visual inspection performed at the same time, the field of view of the microscope is widened and operability is improved.

Also, since the measured waveform is input to the comparator section at a position near the device under test, 1 III fixed device 1
Ill + constant accuracy and inspection accuracy are almost the same as before, and it can meet the requirements for faster testing, clearing the current accuracy and speed levels. Note that if the measurement signal from the device under test is input to the comparator section via an amplifier placed near the device under test, the impedances on the circuit will be matched and the measurement results will be further stabilized.

(Example) An example of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram showing an embodiment in which the present invention is applied to a wafer prober. In the figure, numeral 1 is a wafer prober, which includes, for example, a strobe distributor circuit, a strobe selection circuit, a comparator, although not shown in detail. circuit, high-level comparator pin-to-pin timing adjustment circuit,
The comparator section CM, which is an output signal judgment circuit that compares test results and standard data, and peripheral circuits, consists of a low-level comparator pin-to-pin timing adjustment circuit, a high-level comparator, a low-level comparator, a D/A conversion circuit, etc. A test head 2, which has a built-in board and performs comprehensive control of various electrical characteristic tests of the device under test DUT, is separated from the tester 3 and placed directly on a wafer prober in the vicinity of a probe card 4. As with conventional wafer probers, the device under test DUT and test head 2 of Ueno The tester 3 and the test head 2 are connected by a connection cable or the like.

In addition, when applying the inspection device of the present invention, structurally,
It does not necessarily have to be as described above.

In this embodiment, the test head 2 includes only the peripheral circuit board and the conventional pin electronics section PE, including the combiner 90 structure, such as a timing generation circuit, a Glock distributor circuit, a clock selection circuit, a waveform The driver section DR consists of a modulation circuit, a pin-to-pin timing adjustment circuit, a driver drive circuit, a D/A conversion circuit, etc., and provides voltage, timing, etc. to the device under test according to the test program using control signals.
is removed from the pin electronics section PE and placed outside the test head 2 in the middle of the connection cable between the tester 3 and the test head 2. Test head 2 like this
The comparator section CM built in the probe card 4
The measurement signals passing through the probe and the peripheral circuit board are compared and the results are sent to the tester 3 via the connecting cable. In this case, the test head 2 (therefore, the comparator section C
Since the device M) is located very close to the device under test DUT, there is no problem when comparing the measurement signals by the probe, the speed of the test is not delayed, and the same accuracy as before can be maintained. Note that the comparator section CM may incorporate a highly accurate timing correction mechanism and other circuits.

In addition, the driver unit DR placed in the middle of the connection cable between the tester 3 and the test head 2 exchanges signals such as measurement signals with the tester 3. Even if it is located outside, the function as the driver section DR will not be impaired.

FIG. 2 is a partial circuit diagram showing the connection relationship between the device under test DUT, the comparator section CM, and the driver section DR in another embodiment of the present invention. A preamplifier is installed between the two. In this embodiment, as shown in the figure, by further providing a preamplifier near the device under test DUT, it is possible to cope with the case where the distance between the driver section DR and the device under test DUT is increased, and This is for impedance matching.

Further, in each of the above embodiments, the comparator section CM is built into the test head 2, but it is not necessarily built into the test head 2. For example, the comparator section CM
It is also possible to mount the comparator section CM on the probe card 4 and position the comparator part CM at the shortest distance from the probe, which is preferable from the standpoint of measurement accuracy. The comparator unit CM may be configured to be mounted within the probing area as close as possible to the device under test DUT at the time of measurement, or may be configured to be moved and located at the time of inspection. It may be configured to be located in a fixed position.

Next, the operation of the above embodiment will be explained.

According to this embodiment as described above, the test head 2 does not have a built-in tri-bar portion D R having a considerable weight, so the test head 2 is made lighter and smaller, and the operability of the inspection device α is significantly improved. . By reducing the weight of the test head 2, the rotation mechanism of the wafer prober 1 can also be made smaller. In addition, since the heat generated by the driver part DR does not affect the semiconductor devices on the semiconductor wafer 5 at all, the cooling fan inside the test head 2 is no longer necessary, resulting in further downsizing and weight reduction. This prevents damage to the semiconductor devices caused by the stylus, and quality defects of the semiconductor devices on the semiconductor wafer 5 due to the influence of dust falling due to the cooling fan.

By reducing the size and weight in this way, the measurement distance between the semiconductor device on the semiconductor wafer 5 and the comparator section CM can also be shortened, and the signal measured by the probe can be immediately observed from the outside at the time of measurement. It is also possible to improve the operability of the
C: Sufficient support for LSI (device under test). In addition, in the external visual inspection performed at the same time, the field of view of the microscope 6 is widened and operability is improved.

The test head section 2 also includes a pin electronics section P.
Since the comparator section CM of E is built-in, or the comparator section CM of the pin electronics section PE is mounted on a probe card, etc., and the comparator section CM is placed near the probe, a more complete measurement waveform can be input to the comparator section CM. Therefore, the measurement accuracy and inspection accuracy of semiconductor devices on semiconductor wafers remain almost the same as before, and the test speed can be increased, exceeding the current accuracy and speed levels. Note that an amplifier PA is installed near the semiconductor wafer 5 between the semiconductor device on the semiconductor wafer 5 and the comparator section CM.
If it is provided, the impedance on the circuit will be matched and the measurement results will be more stable.

According to the present invention described above, in particular, in a test and inspection apparatus for a semiconductor device under test, the comparator section of the pin electronics section that transmits and receives measurement signals between the tester and the probe card is connected to the device under test. On the other hand, the driver section of the pin electronics section is placed outside the measurement area of the device under test.
The test head is lighter and smaller, and the operability of the inspection equipment is significantly improved. Therefore, it is possible to provide an inspection apparatus that can sufficiently cope with higher integration of semiconductor devices such as 128 pins or 256 pins in the future. By reducing the weight of the test head, attached mechanisms such as the rotating mechanism of the inspection device can also be made smaller and lighter, and the inspection device can also be standardized and shared, contributing to a substantial cost reduction.

In addition, it is now possible to fully handle a wide variety of devices under test, and furthermore, by being smaller and lighter, 11! The measurement distance between the constant device and the comparator section can be shortened, which not only leads to improved accuracy, but also
Since the signal measured by the probe can be observed from the outside immediately at the time of measurement, it is also possible to improve the operability of the probe.

Note that if the measurement signal from the device under test is input to the comparator section via an amplifier placed near the device under test, impedance matching on the circuit can be achieved and the distance from the driver section can be improved. Inspection 81 can be stably performed at high speed and with high accuracy even when the test is performed. It has the following effects.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment in which the present invention is applied to a wafer blobber, and FIG. 2 is a diagram showing the connection relationship between a device under test, a comparator section, and a driver section in another embodiment of the present invention. 3 is a schematic diagram showing an example of a conventional wafer prober, and FIGS. 4(a) and 4(b) are diagrams showing the head portion of the conventional example, and (a) is an exploded perspective view.
(b) is a plan view and a sectional view in the assembled state, FIG. 5 is a diagram showing the connection relationship between the pin electronics part of the conventional test head and the device under test, and FIG. 6 is the other side of the conventional wafer prober. It is a schematic diagram. ■...Wafer prober, 2...Test head,
3...Tester, 4...Probe card. 5... Semiconductor wafer, DUT... Device under test,
PE...Pin electronics section, CM...Comparator section, DR...Driver section. Figure 4 (a) (b) Figure 5

Claims (2)

[Claims] (1) A test and inspection apparatus for semiconductor devices under test, in which the comparator section of the pin electronics section, which exchanges measurement signals between the tester and the probe card, is located near the device under test; A semiconductor inspection system in which the driver section of the electronics section is placed outside the measurement area of the device under test. (2) The semiconductor inspection apparatus according to claim 1, wherein the measurement signal from the device under test is input to the comparator section via an amplifier.