JP3225536B2 - Micro device evaluation equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a microwave IC (MM)
The present invention relates to a microdevice evaluation device suitable for use in evaluating characteristics of ultra-high-speed devices such as ICs (micromonolithic ICs; hereinafter simply referred to as MMICs) and quantum devices.

[0002]

2. Description of the Related Art In recent years, with the speeding up of devices, devices using compound semiconductors and MMICs and quantum effects have been manufactured.

[0003]

However, the above-mentioned device cannot monitor the quality of the performance at the wafer stage, so that even if the device is defective, the process proceeds to the subsequent steps, which is extremely uneconomical. Further, since the occurrence of defective products cannot be easily found, subsequent lots manufactured under the same conditions may also be defective products. SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a micro device evaluation apparatus which can easily evaluate a product even at a wafer stage.

[0004]

In order to solve the above-mentioned problems, according to the present invention, there is provided an evaluation signal generating means formed on a semiconductor substrate and an end portion of the semiconductor substrate.
Device to be measured having a plurality of probe pins formed
Outputs the evaluation signal to the
A signal generating probe that is formed on a semiconductor substrate and
An output signal from the device under test is applied to an end of the semiconductor substrate.
Through a plurality of probe pins formed on part type having a performance evaluation means for evaluating the performance of the device under test
A receiving probe, wherein the plurality of probe pins are
High-speed, high-speed operation while forming by etching a semiconductor substrate
The wave signal is formed so short that the wave signal can be normally transmitted and received .
In the micro device evaluation apparatus, a pulse laser transmitting means, a variable optical delay means for inputting the pulse laser and controlling a pulse output thereof, and an electro-optical probe for outputting a signal from the variable optical delay means via a transmission optical fiber And a function evaluation unit that converts light from the receiving optical fiber into an electric signal and performs signal processing to evaluate a function of a predetermined portion of the device under test.

[0005]

According to the first aspect, the signal from the evaluation signal generating means is transmitted to the device under test via the probe, The performance evaluation means takes in the output signal from the device under test via the probe and evaluates the quality of the device under test. 3. An optical pulse according to claim 2, wherein when the electro-optic probe is brought closer to the circuit of the device under test, the electric field that seeps above the circuit causes a small change in birefringence in the electro-optic crystal, which is then reflected back through the crystal. Change the amplitude. That is,
Since the electric field changes due to the crystal inside the IC, the change in the reflected light that changes in accordance with the change in the electric field is received by the receiving optical fiber, and the light is converted into an electric signal to perform signal processing.

[0006]

FIG. 1 is a block diagram showing an embodiment of a micro device evaluation apparatus according to the present invention, and FIG. 2 is a conceptual diagram of a measurement system using the present apparatus. In FIG. 1, reference numeral 1 denotes a signal generation probe as evaluation signal generation means, for example, 5 × 10 ×
It is formed on a silicon substrate having a size of about 0.5 mm. A power supply connection terminal 2 and a drive circuit 3 are formed on the probe 1, and an ultrashort electric pulse (ps to fs... Picosecond to femtosecond) is generated partially using a technique such as GaAs-On-Si. A means 4 and a high frequency (GHz to THz) signal generating means 5 are formed. Reference numeral 6 denotes a probe pin, which is formed by using a known technique such as photolithography or anisotropic etching of silicon. The probe pin is desirably as short as possible to transmit a high-speed and high-frequency signal.

Reference numeral 7 denotes a device to be measured.
Quantum effect devices and M devices using technologies such as s-On-Si
A high-speed high-integration circuit such as an MIC is formed, and input / output terminals (pads) 8 for evaluation are formed at predetermined positions. 1
Numeral 0 denotes a receiving probe as a performance evaluation means. The receiving probe includes a sampler / mixer 11 and an ultra-high-speed A / D which are formed partially using a technique such as GaAs-On-Si.
It has a converter 12 and a signal processing unit 13.

In the above configuration, the signal generation probe 1
Then, a high-frequency signal and an ultrashort pulse signal are applied to the microdevice 7 via the probe pin 6. Receiving process
The probe 10 detects the output from the device under test 7, performs signal processing in the signal processing unit 13, and evaluates the quality of the circuit based on the characteristics and waveforms of the microdevice 7. In the above embodiment, the signal generating probe and the receiving probe are formed on independent semiconductor substrates, but they may be formed on the same substrate.

Next, the second aspect of the present invention will be described. 1
Reference numeral 4 denotes an electro-optic probe, for example, a device under test 7
It is used when it is desired to detect the state of the element in. That is, as shown in the enlarged sectional view of the main part of FIG.
4 has an electro-optic crystal lithium tantalate (LiT)
An aO ₃ ) -polished chip 23 is arranged, and input / output optical fibers 18 and 19 are inserted into the chip 23. 24 is a transmission line. The probe 14 has an ultrashort optical pulse laser 16 driven by a drive circuit 15 on the transmission side and an optical variable delay means 17 for controlling the pulse of the pulse laser. Is guided to the tip of the chip 23 via the optical fiber 18.

When the tip of the electro-optic probe is brought close to the circuit of the device under test 7, the electric field C seeping out of the circuit causes a small change in birefringence in the LiTaO3 crystal, which is then reflected in the crystal. The amplitude of the returning light pulse is changed. That is, since the electric field changes due to the crystal inside the IC, the change in the reflected light that changes in accordance with the change in the electric field is received by the receiving optical fiber 19, and the light is detected by the ultra-high-speed photodetector 20 to be electrically operated. To the MMIC 21
And further performs signal processing via the A / D converter 22. At this time, if the delay time of the variable optical delay means 17 is swept, it is possible to observe a very limited high-speed time waveform.

In the embodiment shown in FIG. 1, although not shown in the drawing, the light from the pulse laser 16 is branched and formed on a part of the ultrashort electric pulse generator 4 of the signal generating probe. When the photoelectric converter is illuminated, the signal of the pulse generator 4 can be synchronized by the photocurrent, and the waveform can be easily observed.

[0012]

As described above in detail with the embodiments, according to the present invention, it is possible to realize a micro device evaluation apparatus capable of easily evaluating a product even at a wafer stage.

[Brief description of the drawings]

FIG. 1 is a configuration perspective view showing an embodiment of a micro device evaluation apparatus of the present invention.

FIG. 2 is a diagram showing the concept of the evaluation device of FIG.

FIG. 3 is an enlarged sectional view of a main part of an electro-optical probe.

[Description of Signs] 1 signal generation probe 2 power supply connection terminal 3 drive circuit 4 ultrashort electric pulse generator 5 high frequency signal generator 6 probe pin 7 device under test 8 input / output terminal 10 reception probe 11 sampler / Mixer 12 Ultra-high-speed A / D converter 13 Signal processing unit 14 Electro-optic probe 15 Drive circuit 16 Ultra-short optical pulse laser 17 Optical variable delay means 18, 19 Optical fiber 20 Ultra-high-speed photodetector 21 MMIC 22 A / D converter 23 Crystalline lithium tantalate 24 Transmission line

Claims (2)

(57) [Claims] 1. An evaluation signal generating means formed on a semiconductor substrate and a plurality of probe pins formed at an end of the semiconductor substrate, wherein the evaluation signal is transmitted to a device under test via the probe pins. And a signal generation probe that outputs the signal from the device under test, and outputs an output signal from the device under test through a plurality of probe pins formed at an end of the semiconductor substrate to improve the performance of the device under test. A plurality of probe pins formed by etching the semiconductor substrate and formed short enough to transmit and receive high-speed high-frequency signals normally. Device evaluation equipment. 2. A pulse laser transmitting means, a variable optical delay means for inputting the pulse laser and controlling a pulse output thereof, and an electro-optical probe for outputting a signal from the variable optical delay means via a transmission optical fiber. 2. A micro-processor according to claim 1, further comprising function evaluation means for converting light from said receiving optical fiber into an electric signal and performing signal processing to evaluate a function of a predetermined portion of said device under test. Device evaluation equipment.