This application claims the benefit of priority to Korean Patent Application No. 10-2017-0133184 filed on Oct. 13, 2017, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.
The present disclosure relates to a semiconductor chip inspection device.
In a process of manufacturing semiconductor chips, a plurality of processes are sequentially performed. Thus, in a case in which defects occur in any one process, defects may be present until a final process. Thus, in order to improve productivity, a process of detecting and removing a defective semiconductor chip before a manufacturing process is completed is significant. In the case of optical inspection equipment or electron-beam (e-beam) inspection equipment, defects visible on the surface of semiconductor chips may be easily detected, but there are limitations in detecting defects occurring inside of semiconductor chips. Since an inspection to confirm whether semiconductor chips are able to operate normally by supplying power to semiconductor chips is possible after semiconductor chips have been manufactured, there have been limitations in removing defective semiconductor chips in an early stage.
An aspect of the present inventive concept is to provide a semiconductor chip inspection device detecting a defect in a semiconductor chip in an early stage.
According to one embodiment, a semiconductor chip inspection device includes a conveyor, an image capture device, and an analysis system. The conveyor provides a transfer path on which a semiconductor chip heated during a manufacturing process is moved. The image capture device is disposed above the transfer path and is configured to generate a thermographic image by imaging the semiconductor chip including capturing a plurality of thermographic images at different focal points in a thickness direction of the semiconductor chip. The analysis system is configured to compare the plurality of thermographic images with a plurality of standard images provided in advance, and to detect a region in which a temperature differential between a thermographic image and a respective standard image exceeds a reference value.
According to one embodiment, a semiconductor chip inspection device includes a chamber, a conveyor, an image capture device, and an analysis system. The conveyor is accommodated in the chamber and provides a transfer path on which a semiconductor chip, heated to a temperature higher than a temperature in the chamber, is moved. The image capture device is disposed above the transfer path and is configured to generate a thermographic image by imaging the semiconductor chip, including capturing a plurality of thermographic images at different focal points in a thickness direction of the semiconductor chip. The analysis system is configured to generate a thermographic image group by processing the plurality of thermographic images and detecting a region in which a temperature differential between the thermographic image group and a standard image group, provided in advance, exceeds a reference value, to detect a defect in the semiconductor chip.
According to one embodiment, a semiconductor chip inspection device includes a transfer portion, a shooting portion, and an analysis portion. The transfer portion provides a transfer path on which a semiconductor chip cooled from a first temperature to a second temperature during a transfer process is moved. The shooting portion is disposed above the transfer path and is configured to capture a thermographic image of the semiconductor chip. The analysis portion is configured to detect a region in which a temperature differential exceeds a reference value by comparing the thermographic image with a plurality of standard images provided in advance, while detecting a section having a highest temperature and a section having a lowest temperature in the thermographic image and multiplying values of the thermographic image by an amplifier factor allowing a temperature differential in the section having a highest temperature and the section having a lowest temperature to be increased.
The above and other aspects, features, and advantages of the present disclosure will be more clearly understood from the following detailed description, taken in conjunction with the accompanying drawings, in which:
of
Hereinafter, example embodiments will be described with reference to the accompanying drawings.
With reference to
As used here, a semiconductor chip refers to a die formed from a semiconductor wafer and including an integrated circuit thereon. A semiconductor chip can be a memory chip or a logic chip, for example. A semiconductor chip may be more generally referred to as a semiconductor device, which term is also used to describe a semiconductor package. A semiconductor package may include one or more semiconductor chips stacked on a package substrate, and covered by a molding layer. A semiconductor package may also refer to a package-on-package device including a plurality of packages formed in a stack.
With reference to
The semiconductor chip inspection device 10 may be disposed on a transfer path between processes of manufacturing the semiconductor chip. In addition, in some embodiments, the semiconductor chip inspection device 10 may be disposed between a process of heating the semiconductor chip and a subsequent process thereof in a manufacturing process. For example, the semiconductor chip inspection device 10 may be disposed between a molding process in which the semiconductor chip is heated while a molding material is placed to cover the semiconductor chip, and a subsequent process thereof (e.g., sorting, marking, or testing) during a process of packaging the semiconductor chip. In this manner, inspection of the semiconductor chip by the semiconductor chip inspection device 10 may occur after the semiconductor chip is in package form, including an encapsulating molding layer.
The semiconductor chips P1 and P2 loaded into the semiconductor chip inspection device 10 of an example embodiment may be provided in a state of being heated to a first temperature in the previous process. The semiconductor chips P1 and P2 heated may be gradually cooled to a second temperature in a process of being transferred in the semiconductor chip inspection device 10. According to an example embodiment, a temperature measuring device measuring a temperature of the semiconductor chip may be disposed in an inlet portion IN and an outlet portion OUT of the semiconductor chips P1 and P2 of the semiconductor chip inspection device 10. For example, the temperature measuring device may include one or more temperature sensors connected to a processor. The processor maybe part of the analysis portion 400, or may be separate from the analysis portion 400. In a case in which a decrease in a temperature measured in the inlet portion IN and the outlet portion OUT exceeds a reference value, a temperature maintaining system reducing a speed at which the semiconductor chips P1 and P2 are cooled may be included therein.
The previous process is provided as a process of inevitably heating the semiconductor chip in a process of manufacturing the semiconductor chip and refers to a process in which the semiconductor chip is heated in a process of forming an encapsulation layer on an exterior of the semiconductor chip using the molding material in a manner similar to the molding process cited as an example. In detail, when the semiconductor chip is heated in the molding process, the first temperature may be within a range of 130° C. to 150° C., while the second temperature may be room temperature. Thus, in the case of an example embodiment, since a separate heating device for heating the semiconductor chip before being loaded into the semiconductor chip inspection device 10 is unnecessary, a delay of the manufacturing process caused by further heating the semiconductor chip to be inspected may be prevented. The semiconductor chips P1 and P2 of an example embodiment may be provided as a packaged semiconductor chip, but are not limited thereto. For example, the semiconductor chips P1 and P2 may be provided as a semiconductor chip in a state before being packaged, or in a wafer state, and in certain embodiments, inspection may occur after a natural heating process during the processing of the semiconductor chip or wafer.
The chamber 100 may be disposed on a moving path connecting a chamber C1 of the previous process to a chamber C2 of a subsequent process. The chamber 100 may be provided to have a size sufficient to accommodate the transfer portion 200 in an internal space thereof. According to an example embodiment, the chamber 100 may be provided to have a size sufficient to accommodate the shooting portion 300 therein. An observation window may also be disposed on a side wall thereof, in order to observe an interior of the chamber 100 from an exterior thereof.
An internal temperature of the chamber 100 may be lower than a first temperature, such as a temperature of the semiconductor chips P1 and P2 entered through the inlet portion IN. Thus, the semiconductor chips P1 and P2 may be cooled while being moved in the interior of the chamber 100. The chamber 100 may be an enclosed space, having four walls, a top ceiling, and a bottom floor, and may have one or more doors or entryways through which the semiconductor chips P1 and P2 may enter and exit.
The transfer portion 200, which may be a conveyor, may connect the chamber C1 of the previous process to the chamber C2 of the subsequent process and may employ various transfer means continuously transferring the semiconductor chip along a predetermined path. In an example embodiment, a conveyor belt may be employed.
The shooting portion 300 may be disposed above a transfer path of the semiconductor chips P1 and P2 and may capture a thermographic image of the semiconductor chips P1 and P2 to be transmitted to the analysis portion 400.
As illustrated in
In an example embodiment, a thermographic image of the semiconductor chip may be imaged to be compared with the thermographic image of the semiconductor chip normally operated (e.g., having no defects), thereby confirming whether the semiconductor chip has a defect or not. A defect occurring in a process of manufacturing the semiconductor chip may occur, for example, when a lithography process or an etching process is not performed as desired, when a foreign substance is introduced from an external source during a manufacturing process, when a chemical change, such as oxidation, occurs in a structure formed using a semiconductor layer, or when a crack occurs therein. Due to a difference in physical properties of defect, a region in which the defect has occurred has a difference in thermal conductivity from the same region of a normal, non-defective semiconductor chip. Thus, heat emitted from the region in which the defect has occurred has a distribution different from that of heat emitted from the same region of a normal, non-defective semiconductor chip. Since infrared light wavelengths generated by heat described above have a higher level of transmittance than that of light having other wavelengths, infrared light wavelengths emitted from a lower portion of the semiconductor chip may be easily detected.
In an example embodiment, a thermal distribution of the semiconductor chip may be confirmed through a thermographic image to be compared with a thermal distribution of a normal (e.g., non-defective) semiconductor chip, thereby confirming whether a defect has occurred in the semiconductor chip being measured.
According to an example embodiment, the thermographic cameras 310 and 320 may be connected to moving stages 311 and 321, respectively. Thus, according to need, a plurality of thermographic images may be captured in such a manner that the thermographic cameras 310 and 320 are moved to the left or right, or a focal point is changed in a thickness direction of an object by moving the thermographic images up and down.
The thermographic camera 310 may capture thermographic images of virtual layers L1, L2, and L3, stacked in the thickness direction at different focal points F1, F2, and F3. Each virtual layer corresponds to a constant vertical height within the semiconductor chip and the items and components of the chip that exist at that vertical height. The thermographic camera 310 may sequentially capture a thermographic image in a direction from a layer L1 corresponding to a surface of a semiconductor chip P1 to a layer L3 disposed in a lowermost portion of the semiconductor chip P1 at different focal points of a lens 312. According to an example embodiment, the thermographic image may be captured by sequentially increasing a focal length in the thickness direction of the semiconductor chip P1 before the thermographic image of a transfer portion 200 is captured. Thus, a plurality of thermographic images according to thicknesses of various types of semiconductor chips having different thicknesses may also be captured.
According to an example embodiment, a thermographic camera may be disposed in an inlet portion IN and an outlet portion OUT of a semiconductor chip inspection device 10, and an average value of a thermographic image captured by the thermographic camera may be calculated, thereby measuring temperatures of the components or regions of semiconductor chips P1 and P2 as an average. For example, a first image at a first temperature may show certain first temperature distributions, and a second image at a second temperature may show certain second temperature distributions. The temperature distributions may show up as different intensities of detected heat. Thus, the two images may be averaged to result in an averaged image for each of the semiconductor chips. Thus, the shooting portion 300 may include first cameras (e.g., one or more cameras to shoot one or more respective semiconductor chips) for shooting the semiconductor chips near the inlet portion IN of the semiconductor chip inspection device 10, and may include second cameras (e.g., one or more cameras to shoot one or more respective semiconductor chips) for shooting the semiconductor chips near the outlet portion OUT of the semiconductor chip inspection device 10
An analysis portion 400 may compare a thermographic image captured by a shooting portion 300 with a plurality of standard images provided in advance to detect a region in which a temperature differential (e.g., between the captured thermographic image and one of the standard images) exceeds a reference value, thereby detecting a defect in the semiconductor chips P1 and P2. The analysis portion 400, also described as an analysis system, may be implemented by a computer and may include known computer technology, such as processing and memory hardware, input/output interfaces, and various software programs that configure the analysis system to perform this detection by performing various calculations and comparisons such as described herein. Also, it should be noted that as is traditional in the field of the disclosed technology, features and embodiments are described, and illustrated in the drawings, in terms of devices or systems relating to processing technology, such as computers. Those skilled in the art will appreciate that these devices and systems are physically implemented by electronic (or optical) circuits such as logic circuits, discrete components, microprocessors, hard-wired circuits, memory elements, wiring connections, and the like, and they may be programmed using software (e.g., microcode) to perform various functions discussed herein and may optionally be driven by firmware. Also, devices or systems of the embodiments may be a single device (e.g., standalone computer) or may be physically separated into two or more interacting and discrete units without departing from the scope of the inventive concepts.
Descriptions of this detection process will be provided in detail. For example, in one embodiment, the analysis portion 400 may store a plurality of thermographic images of each of the semiconductor chips P1 and P2 captured in the shooting portion 300, to be processed, thereby generating a thermographic image group corresponding to each of the semiconductor chips P1 and P2. In this case, the analysis portion 400 may perform signal processing to amplify a defective signal, in order to emphasize the defective signal included in the thermographic image. As an example of the signal processing described above, a region having the highest temperature and a region having the lowest temperature in a captured thermographic image may be detected, and an amplifier factor allowing a temperature differential in sections described above to be increased may be multiplied by a value, thereby emphasizing the defective signal compared with other signals.
In addition, the analysis portion 400 may process a plurality of standard images provided in advance, thereby generating a standard image group. The analysis portion 400 may compare the standard image group with respective thermographic image groups and detect a region in which a temperature differential exceeds the reference value, thereby determining whether a defect has occurred in the semiconductor chips P1 and P2. The plurality of standard images may be provided as data previously stored in the analysis portion 400 and may include data storing a thermographic image of a semiconductor chip which may commonly be discriminated.
Descriptions thereof will be provided in detail with reference to (a) of
(a) to (c) of
The analysis portion 400 may process thermographic images IMGL1 to IMGL3 of (a) to (c) of
Since (a) of
According to an example embodiment, a semiconductor chip inspection device 10 may further include a sorting system sorting and removing a semiconductor chip confirmed as having a defect. For example, the sorting system may include a mechanical sorting track or robot arm configured by software to sort and remove a semiconductor chip confirmed as having a defect.
The semiconductor chip inspection device 10′ of
Subsequently, with reference to
First, the semiconductor chip heated to a first temperature in the previous process may be loaded into a semiconductor chip inspection device 10 in S1. A semiconductor chip P1 may be continuously transferred along a transfer path on a transfer portion 200 of the semiconductor chip inspection device 10 by a predetermined interval. Descriptions below are a case in which the semiconductor chip P1 is loaded into the transfer portion 200, and a temperature value of the semiconductor chip, having been previously loaded, is stored in the analysis portion 400.
The analysis portion 400 may confirm whether a temperature value of a semiconductor chip stored therein is lower than a reference value and determine whether a temperature of the semiconductor chip P1 transferred along the transfer path may be adjusted, in S2. In a case in which a temperature is required to be adjusted, a temperature maintaining system reducing a decrease in a temperature of the semiconductor chip may be operated in S3.
Subsequently, a shooting portion 300, also described as an image capture device may capture a thermographic image of the semiconductor chip P1 to be transmitted to the analysis portion 400 in S4.
The analysis portion 400 may determine whether signal amplification of the thermographic image, having been transmitted, is required, in S5. If necessary, the analysis portion 400 may detect a section having a highest temperature and a section having a lowest temperature in the thermographic image and may multiply a value of a thermographic image in the section having a highest temperature and the section having a lowest temperature by an amplifier factor allowing a temperature differential to be increased in S6.
The analysis portion 400 may compare a standard image stored in advance with the thermographic image in S7 and may determine whether a defect is imaged in an thermographic image captured by performing a subtraction process in S8. If no defect is present (S7, NO), then the semiconductor chip is transferred to the next manufacturing process. For example, this process could be a marking process or a testing process, or sorting the semiconductor chip into a non-defective chip group.
The analysis portion 400 may confirm the semiconductor chip, corresponding to the thermographic image on which a defect is imaged, is defective in S9 and as a result, the semiconductor chip is selectively removed from the manufacturing process in S10 (e.g., in a sorting process).
As set forth above, according to example embodiments of the present disclosure, a semiconductor chip inspection device may detect a defect in a semiconductor chip in an early stage, thereby improving productivity.
While example embodiments have been shown and described above, it will be apparent to those skilled in the art that modifications and variations could be made without departing from the scope of the present invention as defined by the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
10-2017-0133184 | Oct 2017 | KR | national |