JP2007327817A - Inspection device and inspection method for semiconductor element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection device and an inspection method for semiconductor elements which are preferred for parallel processing, and which can also reduce the inspection cost. <P>SOLUTION: The inspection device for inspecting a plurality of semiconductor elements by using parallel processing through being connected to them, respectively, comprises a drive circuit for outputting a drive signal to the semiconductor elements; a correlated double sampling circuits for eliminating the noise of the image signals outputted from the semiconductor elements; and a serial processing circuit for converting the signals outputted from the respective correlation double sampling circuits into a single serial signal. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a semiconductor element inspection processing apparatus, and more particularly to a semiconductor element inspection apparatus and inspection method for simultaneously inspecting a plurality of semiconductor elements formed on a semiconductor wafer.

  In the inspection process of a semiconductor element such as a solid-state image sensor, after the semiconductor element is formed on the semiconductor wafer, the probe needle of an inspection device such as a probe card is brought into contact with the circuit board of the semiconductor element to detect the output signal. (For example, refer to Patent Document 1 below). FIG. 4 is a diagram illustrating signal processing in a conventional semiconductor element inspection process. In general, in the inspection of semiconductor elements, output signals from a plurality of semiconductor elements (in FIG. 4, four cases are shown) are processed in parallel to ensure throughput.

JP 2000-216204 A

  By the way, when performing parallel processing, AD boards and image processing boards connected to each processing system are expensive, and the number of processing systems increases in proportion to the number of semiconductor elements to be inspected. There was room for improvement in that the cost tends to be high. In addition, there is a concern that the measurement values vary among image processing systems for each semiconductor element. Further, in the inspection, the AD board and the memory on the image processing board may not always be fully utilized. For example, in the case of inspection of a solid-state image sensor with a small number of pixels, a solid state of 1M pixels is used. When the image sensor is processed by an 8M mounted AD board, the performance is 1/8.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a semiconductor device inspection apparatus that is suitable for parallel processing of semiconductor device inspection and can reduce the cost of inspection. .

  The object of the present invention is a semiconductor element inspection apparatus for inspecting a plurality of semiconductor elements by parallel processing, and is connected to each of the plurality of semiconductor elements to be inspected and outputs a drive signal to the semiconductor elements. A drive circuit; and a correlated double sampling circuit connected to each of the semiconductor elements and removing noise of an image signal output from the semiconductor element, and an output signal output from each of the correlated double sampling circuits This is achieved by an inspection device characterized in that a serial processing circuit for converting the signal into one serial signal is provided.

  The above-described object of the present invention is a semiconductor element inspection method for inspecting a plurality of semiconductor elements by parallel processing, wherein a drive signal is input to each of the plurality of semiconductor elements to be inspected by a drive circuit, A correlated double sampling circuit connected to each of the semiconductor elements removes noise of the image signal output from the semiconductor element, and an output signal output from each of the correlated double sampling circuits is converted into a serial processing circuit. This is achieved by an inspection method characterized in that it is converted into a single serial signal.

  The present invention includes a serial processing circuit and converts the output signal output from the correlated double sampling circuit of the processing system provided for each semiconductor element into one serial signal, thereby integrating the processing system into one. It is a configuration. For this reason, AD boards and image processing boards that process serial signals converted by the serial processing circuit may be installed one by one. Even if the processing system increases in proportion to the number of semiconductor elements to be inspected, It is possible to prevent the cost for the inspection process from increasing. Also, by converting the processing system into a serial signal and integrating it into one processing system, it is possible to prevent variations in measured values between image processing systems for each semiconductor element, and to improve inspection accuracy. .

  The serial processing circuit is preferably a multiplex circuit. In this way, the output signal output from the processing system provided for each semiconductor element can be converted into one serial signal by the multiplex circuit, and the processing system is integrated into one for the inspection process. Increase in cost can be prevented.

  ADVANTAGE OF THE INVENTION According to this invention, it is suitable for the parallel processing of the test | inspection of a semiconductor element, and the test | inspection apparatus of the semiconductor element which can reduce the cost concerning a test | inspection can be provided.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a configuration of a semiconductor element driving apparatus according to the present invention. In this embodiment, a solid-state imaging device will be described as an example of a semiconductor element. However, the semiconductor element according to the present invention is not limited to a solid-state image sensor, and can be applied to, for example, inspection of a CMOS type image sensor.

  The inspection apparatus acquires image data of a plurality (four in the present embodiment) of semiconductor elements indicated by CCD1 to CCD4 in FIG. 1, and performs signal processing to perform a predetermined inspection based on the image data.

  The inspection apparatus is connected to each of a plurality of semiconductor elements to be inspected, and is provided with a drive circuit that outputs a drive signal to each of the plurality of semiconductor elements at the time of inspection.

  Further, a correlated double sampling circuit (also referred to as a CDS circuit) indicated by CDS 1 to 4 in FIG. 1 is connected to each of the plurality of semiconductor elements. The correlated double sampling circuit is a circuit for suppressing noise of a pixel signal, and obtains a pixel signal composed of a pair of a pedestal level (generally a black level) and a signal level from a solid-state imaging device, and obtains a pedestal. The level is clamped to the clamp potential, and the clamp is released during the scanning period in which the signal level is output, and the change from the pedestal level to the signal level is sampled and held. In particular, a light-shielding area is provided on an array of solid-state imaging devices such as CCDs, and the pixel signal of this light-shielding area is fixed as a black level.

  At the time of inspection, a drive signal is output from the drive circuit to each of the semiconductor elements, and image signals generated by a plurality of semiconductor elements are output to the double sampling circuit. In the present embodiment, each of the semiconductor elements and the double sampling circuit constitute one processing system, that is, four processing systems are formed for four semiconductor elements.

  The inspection apparatus according to this embodiment is provided with a serial processing circuit to which output signals output from the respective double sampling circuits are input. The serial processing circuit of this embodiment uses a multiplex circuit (also referred to as a MUX circuit). The serial processing circuit is configured to take in a plurality of output signals from a semiconductor element and switch the transfer lines to output a digital signal when the output signals are transferred through the plurality of transfer lines.

FIG. 2 is a diagram showing the respective values of the output signal from the solid-state imaging device of the present embodiment and the output signal of the multiplex circuit in time series.
In this embodiment, G1, B, G2, and R (green is two signals) out of image signals that are output signals output from each of the four solid-state imaging devices are converted into one serial signal by serial processing. To do.

  As shown in FIG. 1, the serial signal output from the serial processing circuit is output to the AD board via an amplifier (AMP), and after AD conversion, is output to the image processing board. In the inspection apparatus of this embodiment, one serial signal is output to a single processing system having one AD board and one image processing board by the serial processing circuit, and signal processing is performed. In this embodiment, since the frequency per pixel is four times, it is particularly suitable for a semiconductor element with a small number of pixels and low frequency driving.

  The serial signal output from the serial processing circuit is stored in the memory of the AD board, and then the signal stored in the memory of the AD board is transferred to the video memory of the image processing board at a predetermined timing. In this way, four types of signals R, G1, G2, and B of the four semiconductor elements can be processed by one image processing board.

  FIG. 3A shows information stored in the memory of each AD board when parallel processing is performed in the inspection of semiconductor elements by a conventional inspection apparatus. FIG. 3B shows information stored in the memory of the AD board when the semiconductor device is inspected by the inspection apparatus of this embodiment. In the conventional inspection apparatus shown in FIG. 3A, only a partial area of the memory of the AD board is used, which is wasteful. However, in the inspection apparatus of this embodiment, as shown in FIG. 3B, the pixels of four semiconductor elements can be stored in the memory of one AD board, and the number of pixels that can be stored is normally 4 The AD board processing performance can be improved.

  The configuration includes a serial processing circuit and converts the output signal output from the correlated double sampling circuit of the processing system provided for each semiconductor element into one serial signal, thereby integrating the processing system into one. For this reason, AD boards and image processing boards that process serial signals converted by the serial processing circuit may be installed one by one. Even if the processing system increases in proportion to the number of semiconductor elements to be inspected, It is possible to prevent the cost for the inspection process from increasing. Also, by converting the processing system into a serial signal and integrating it into one processing system, it is possible to prevent variations in measured values between image processing systems for each semiconductor element, and to improve inspection accuracy. .

  In addition, this invention is not limited to embodiment mentioned above, A suitable deformation | transformation, improvement, etc. are possible.

It is a figure which shows the structure of the drive device of the semiconductor element concerning this invention. It is a figure which shows each value of the output signal from the solid-state image sensor of this embodiment, and the output signal of a multiplex circuit in time series. (A) It is a figure which shows the information stored in the memory of each AD board when parallel processing in the test | inspection of a semiconductor element with the conventional test | inspection apparatus. (B) It is a figure which shows the information stored in the memory of AD board when test | inspecting a semiconductor element with the test | inspection apparatus of this embodiment. It is a figure which shows the signal processing of the test | inspection process of the conventional semiconductor element.

Explanation of symbols

CCD1 to CCD4 Solid-state image sensor (semiconductor element)
AD AD board

Claims (4)

A semiconductor device inspection apparatus for inspecting a plurality of semiconductor elements by parallel processing,
A drive circuit connected to each of a plurality of semiconductor elements to be inspected and outputting a drive signal to the semiconductor elements;
A correlated double sampling circuit connected to each of the semiconductor elements and removing noise of an image signal output from the semiconductor elements;
An inspection apparatus comprising a serial processing circuit for converting an output signal output from each of the correlated double sampling circuits into one serial signal.   The inspection apparatus according to claim 1, wherein the serial processing circuit is a multiplex circuit. A method for inspecting a semiconductor element in which a plurality of semiconductor elements are inspected by parallel processing,
A drive signal is input to each of a plurality of semiconductor elements to be inspected by a drive circuit, and noise of an image signal output from the semiconductor element is removed by a correlated double sampling circuit connected to each of the semiconductor elements. And an output signal output from each of the correlated double sampling circuits is converted into one serial signal using a serial processing circuit. The inspection method according to claim 3, wherein the serial processing circuit is a multiplex circuit.

Images