JPH02130942A - Frequency measuring equipment for high frequency oscillation of ic - Google Patents

Abstract

PURPOSE:To enable the leading-out of high frequency in the noncontact manner, measuring the frequency of a led-out signal with a spectrum analyzer or the like, and confirm the oscillation frequency in a wafer state by a method wherein a coaxial probe is used in a probe card, and the extension of its core is made almost parallel to the oscillation signal output wiring. CONSTITUTION:Frequency measuring equipment for high frequency oscillation of an IC is constituted of the following: a probe card 4 provided with a probe to apply a bias to an IC chip 2 in a wafer state and a coaxial type probe transmitting a high frequency signal, a bias voltage power supply 5, and a spectrum analyzer 6. The card 4 is provided with a coaxial probe 7, a probe 8 for bias, and a probe 9 for ground. At the time of measurement, the probes 6 and 9 are brought into contact with the chip 2. The probe 7 is made to approach to a wafer and kept in the non-contact state. A high frequency oscillation circuit in the chip 2 is operated by applying a bias voltage in this manner. By this signal, an electromotive force is induced in the probe 7, and introduced to the spectrum analyzer to be measured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a high-frequency oscillation frequency measuring device for an IC, and particularly to a high-frequency oscillating frequency measuring device for an IC in a wafer state.

[Conventional technology]

Conventionally, when measuring the high frequency oscillation frequency of an IC, as shown in Figure 3, the IC1 after being assembled into a package is used.
2 is mounted on a high-frequency measurement jig, and a spectrum analyzer 6 (or a high-frequency counter) is used for measurement.

[Problem to be solved by the invention]

The conventional IC high frequency oscillation frequency measuring device described above is as follows:
After assembling the IC chip, it is necessary to create a jig for special high-frequency applications.6 Not for normal high-frequency applications.I
In the case of C, the speed test can be performed at the wafer stage, but in the case of ICs for high frequency applications, the test that can be performed at the wafer stage is D.
The C test is the main one, and the speed test is quite difficult.

If high-frequency selection cannot be performed at the wafer stage, the yield after one assembly will be extremely poor, the cost will be high, and the high-frequency characteristics cannot be predicted until assembly.

An object of the present invention is to provide a high-frequency oscillation frequency measuring device for an IC that solves the above-mentioned problems.

[Differences between the invention and the prior art]

In contrast to the conventional IC high-frequency oscillation frequency measuring device described above, the present invention is capable of measuring IC chips in a wafer state, and since measurement is performed without contacting the high-frequency output pad in a wafer state, the stray capacitance of the measurement system is reduced. The difference is that the influence of

[Means to solve the problem]

In order to achieve the above object, the present invention provides an apparatus for measuring the high-frequency oscillation frequency of an IC chip in a wafer state having a high-frequency oscillation circuit, which uses at least three types of probes: a bias probe, a ground probe, and a coaxial probe. a probe card, which is positioned so that only the coaxial probe is in a non-contact state and is substantially parallel to the oscillation output line of the IC chip in the wafer state, and the IC chip in the wafer state; The device includes a power source that applies bias through the probe card, and a frequency measuring device that measures the frequency of a high-frequency signal oscillating within the IC chip in the wafer state.

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

(Embodiment 1) FIG. 1(a) is a circuit block diagram showing Embodiment 1 of the present invention, FIG. FIG. 1(c) is a side view of the same.

In the figure, 1 the high frequency oscillation frequency measuring device of an IC according to the present invention comprises a probe card 4 having a probe for applying a bias to an IC chip 2 in a wafer state and a coaxial probe for passing a high frequency signal; 2, a power supply 5 that applies bias through the probe card 4, and an IC chip 2.
and a spectrum analyzer 6 that measures the high-frequency oscillation frequency output from the probe card 4 through the probe card 4.

The probe card 4 has at least three types of probes: a coaxial probe 7, a bias probe 8, and a ground probe 9. Of these, it is the bias probe 8 and the ground probe 9 that touch the IC chip 2 in the wafer state at the scheduled time of 8I.
The coaxial probe 7 only comes close to the wafer and is not in contact with it.

The probe card 4 is prepared so that the tip L8 of the coaxial probe 7 is substantially parallel to the oscillation output line in the IC chip 2 and is not in contact with the wafer.

At the time of measurement, the IC chip 2 in a wafer state on the wafer stage 1O and the probe card 4 are brought into contact with the probe card 4, and the power supply 5 in the tester probe is turned on to apply a bias to the bias probe 8. When a bias is applied to the IC chip 2 via the bias probe 8, the high frequency oscillation circuit 3 within the IC chip 2 starts to oscillate at a high frequency. This signal causes an induced electromotive force to be generated in the nearby coaxial probe 7 by electromagnetic induction.

This induced electromotive force is measured by a spectrum analyzer 6 using a coaxial line.
Measure the oscillation frequency by guiding the

(Embodiment 2) FIG. 2 is a circuit block diagram showing Embodiment 2 of the present invention. The state of the needle rest during measurement in this example is shown in Figure 1 (
This is the same as b) and (c), and is omitted.

The second embodiment differs from the first embodiment in that a high frequency counter 11 is used instead of the spectrum analyzer 6, and the measurement results of the high frequency counter 11 are transmitted to the tester prober 1.
This is what is output in .

This has the advantage that selection based on the oscillation frequency of the IC becomes possible in real time, and statistical processing can also be performed on the tester side.

〔Effect of the invention〕

As explained above, the present invention uses a coaxial probe in the probe card and positions it so that the extension of the core wire is almost parallel to the oscillation signal output wiring in the IC chip.
High frequencies can be extracted without contacting the oscillation signal output wiring of the IC chip. Furthermore, by measuring the frequency of the extracted signal with a spectrum analyzer or a high-frequency counter, the high-frequency oscillation frequency of the IC can be determined in the wafer state, which has the effect of significantly increasing the IC assembly yield.

Furthermore, since measurements can be made without contacting the oscillation signal output wiring within the IC chip, the influence of the measurement system on the oscillation operation within the IC chip is significantly reduced, resulting in accurate and stable measurements.

[Brief explanation of drawings]

FIG. 1(a) is a circuit block diagram showing Embodiment 1 of the present invention, FIG. 1(b) is a plan view showing the needle stopper state during measurement in Embodiment 1 of the present invention, and FIG. 1(c) is the same side view, the second
The figure is a circuit block diagram showing a second embodiment of the present invention, and FIG. 3 is a circuit block diagram showing a conventional IC high frequency oscillation frequency measuring device. 1... Tester prober 2... IC chip in wafer state 3... High frequency oscillation circuit 4... Probe card 5... Power supply 6... Spectrum analyzer 7... Coaxial probe 8... Bias probe 9... Ground probe 10... Wafer stage 11... High frequency counter

Claims (1)

[Claims] (1) An apparatus for measuring the high-frequency oscillation frequency of an IC chip in a wafer state having a high-frequency oscillation circuit, which has at least three types of needles: a bias probe, a ground probe, and a coaxial probe, and is in a state where the needles are applied. In this case, only the coaxial probe is non-contact, and the probe card is positioned so as to be substantially parallel to the oscillation output line of the IC chip in the wafer state. A high frequency IC, comprising: a power supply that applies a bias to the IC chip in a wafer state through the probe card; and a frequency measuring device that measures the frequency of a high frequency signal oscillating within the IC chip in a wafer state. Oscillation frequency measurement device.