CN209911269U - Transmission light spot infrared thermal imaging detection device - Google Patents
Transmission light spot infrared thermal imaging detection device Download PDFInfo
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- CN209911269U CN209911269U CN201920446840.9U CN201920446840U CN209911269U CN 209911269 U CN209911269 U CN 209911269U CN 201920446840 U CN201920446840 U CN 201920446840U CN 209911269 U CN209911269 U CN 209911269U
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- beam splitter
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Abstract
The utility model discloses a transmission light spot infrared thermal imaging detection device, the device includes controller, heat wave signal acquisition system, chirp beam splitting laser excitation system, test piece protection device four bibliographic categories branch, wherein: the controller is a computer embedded with a LabVIEW platform; the thermal wave signal acquisition system comprises a data acquisition card, a thermal infrared imager and a micro-focus lens; the linear frequency modulation pulse beam splitting laser excitation system comprises a laser driver, a laser transmitter, a reflector, a beam expander and a beam splitter; the test piece protection device comprises a temperature sensor, a sealing box, a buzzer and a single chip microcomputer. The utility model discloses a beam splitting laser principle can make the microcrack defect detection of semiconductor silicon piece comprehensive, can prevent effectively that laser power from crossing high and leading to the semiconductor silicon piece ablation, also can prevent simultaneously that laser power from crossing low and leading to the microcrack defect can not discernment.
Description
Technical Field
The utility model relates to a detect device of silicon chip crazing line defect, concretely relates to pulse beam splitting laser arouses transmission light spot infrared thermal imaging detection device of semiconductor silicon chip crazing line defect.
Background
Semiconductor silicon wafers are used as main substrate materials of integrated circuits, and are the semiconductor materials with the largest production scale, the largest single crystal diameter and the most perfect production process. Statistically, silicon devices account for over 90% of all semiconductor devices sold in the world. Microcrack defects can be generated during the processing of semiconductor silicon wafers.
The commonly used destructive detection methods mainly include a preferential etching method, a step etching method, a cross-section microscopic method and an angle polishing method. Destructive detection methods play a very important role in analyzing surface damage of optical materials and semiconductor crystal materials, but the methods have the defects of time consumption, strong experience dependence and the like besides causing damage to samples. In addition, destructive detection methods are mostly only able to detect local areas and may introduce additional subsurface damage. The infrared thermal wave nondestructive testing is a novel nondestructive testing means, and compared with the conventional testing technology, the infrared thermal wave nondestructive testing has the advantages of non-contact, easy field use, safety, visual testing result, simple and convenient operation and the like. The laser has the characteristics of good monochromaticity, strong directivity, energy concentration, good coherence and the like, and is easy to obtain a uniform temperature field.
LabVIEW is a virtual instrument platform developed by national instruments of America based on the G language. It provides rich data collection, analysis and repository functions and all the functional functions of various instrument communication bus standards including DAQ, VXI. The temperature is collected by the data collection module and transmitted to the single chip microcomputer, the single chip microcomputer transmits data to the Zigbee transmission node, the Zigbee transmission node transmits the data to the Zigbee main control node, the Zigbee main control node transmits the data to the LabVIEW upper computer, the LabVIEW image system transmits the data to the computer, the temperature inside the box body pasted with the reflective film can be comprehensively monitored, if the temperature inside the box body is monitored to exceed 175 ℃, the system can give an alarm, an operator can timely adjust laser power, and ablation of a semiconductor silicon wafer is prevented.
Disclosure of Invention
The utility model aims at providing a transmission light spot infrared thermal imaging detection device of pulse beam splitting laser excitation semiconductor silicon chip crazing line defect. The utility model discloses with pulse beam splitting laser excitation, infrared heat wave detection, sensor principle, LabVIEW software platform, signal algorithm processing combine together, realize that pulse beam splitting laser excites the infrared thermal imaging of transmission light spot of semiconductor silicon chip microcrack defect and detect. The utility model discloses a beam splitting laser principle can make the microcrack defect detection of semiconductor silicon piece comprehensive, can prevent effectively that laser power from crossing high and leading to the semiconductor silicon piece ablation, also can prevent simultaneously that laser power from crossing low and leading to the microcrack defect can not discernment.
The utility model aims at realizing through the following technical scheme:
the utility model provides a transmission light spot infrared thermal imaging detection device of pulse beam splitting laser excitation semiconductor silicon chip crazing line defect, includes controller, heat wave signal acquisition system, linear frequency modulation pulse beam splitting laser excitation system, test piece protection device four bibliographic categories, wherein:
the controller is a computer embedded with a LabVIEW platform;
the thermal wave signal acquisition system comprises a data acquisition card, a thermal infrared imager and a micro-focus lens;
the linear frequency modulation pulse beam splitting laser excitation system comprises a laser driver, a laser transmitter, a reflector, a beam expander and a beam splitter;
the test piece protection device comprises a temperature sensor, a seal box, a buzzer and a single chip microcomputer;
the micro-focus lens is arranged on an optical lens of the thermal infrared imager;
a circular laser incident hole is processed on the left side surface of the sealing box, and a box body door is arranged on the front side surface of the sealing box;
the thermal infrared imager, the beam expander and the beam splitter are arranged in a sealed box;
the temperature sensor is arranged on the inner side of the box body door, and the buzzer and the single chip microcomputer are arranged on the outer side of the box body door;
the reflector is composed of a first reflector and a second reflector;
the data output end of the computer embedded with the LabVIEW platform is connected with the data input end of the data acquisition card;
the data output end of the data acquisition card is connected with the data input end of the laser driver;
the data output end of the laser driver is connected with the data input end of the laser transmitter;
laser emitted by the laser emitter is changed in laser path through the first reflector and the second reflector, enters the seal box through the circular laser incident hole of the seal box, is expanded by the beam expander and is output by the beam splitter;
a semiconductor silicon wafer test piece is arranged between the beam splitter and the thermal infrared imager;
the computer embedded with the LabVIEW platform is connected with the thermal infrared imager;
the temperature sensor is divided into two paths after being processed by the single chip microcomputer, one path is connected with the buzzer, and the other path is connected with a computer embedded with a LabVIEW platform.
Compared with the prior art, the utility model has the advantages of as follows:
1. the utility model discloses utilize laser to have characteristics such as monochromaticity is good, the directionality is strong and good coherence to adopt beam splitting laser excitation semiconductor silicon chip, can make the crazing line defect obtain comprehensive detection, prevent that the condition of lou examining from taking place.
2. The utility model discloses a linear frequency modulation principle can effectively detect less crack defect.
3. The utility model discloses a LabVIEW procedure is nested with the son VI procedure, and it is convenient to call, contacts and controls each other.
4. The utility model discloses place beam expander, beam splitter, silicon chip test piece, little burnt camera lens, thermal infrared imager, temperature sensor in pasting the sealed box that has the reflective membrane, can make temperature sensor detect true ambient temperature, avoid the interference of ambient temperature and noise.
5. The utility model discloses consider that laser energy concentrates, design laser stimulates semiconductor silicon chip, and loading power is too little, makes crackle department defect temperature value and crackle-free department go out the temperature difference and is not obvious, and loading power is too big, then can ablate the silicon chip. Utility model temperature alarm device, exceed 175 ℃, singlechip control's bee calling organ can report to the police, transmits the visual control interface of G language development host computer through the data line, makes LabVIEW main procedure stop through sub VI procedure simultaneously, and the device stop work changes laser power again, and protection semiconductor silicon chip does not receive the damage.
Drawings
FIG. 1 is a schematic structural diagram of a transmitted light spot infrared thermal imaging detection device for micro crack defects of a semiconductor silicon wafer excited by pulse beam splitting laser according to the present invention;
FIG. 2 is a schematic structural view of a semiconductor silicon wafer surface defect transmission measurement system of the present invention;
FIG. 3 is a result diagram of a semiconductor silicon wafer according to the present invention;
FIG. 4 is a diagram illustrating a temperature distribution on a section line of the micro-crack detection according to the present invention;
FIG. 5 is a temperature distribution diagram on a section line of a micro-crack detected by a reflection method;
in the figure: 1. a computer embedded with a LabVIEW platform; 2. a first signal line; 3. a data acquisition card; 4. a second signal line; 5. a laser driver; 6. a third signal line; 7. a laser transmitter; 8. a single laser beam; 9. a first reflective mirror; 10. a second reflective mirror; 11. a circular laser entrance aperture; 12. a sealing box; 13. a beam expander; 14. single beam expanded laser; 15. a beam splitter; 16. splitting the beam of laser light; 17. a semiconductor silicon wafer test piece; 18. a thermal wave signal; 19. a temperature sensor; 20. a single chip microcomputer; 21. a buzzer; 22. a micro-focus lens; 23. a thermal infrared imager; 24. a box door; 25. a fourth signal line; 26. and a fifth signal line.
Detailed Description
The technical solution of the present invention is further described below with reference to the accompanying drawings, but not limited thereto, and all modifications or equivalent replacements of the technical solution of the present invention are included in the protection scope of the present invention without departing from the spirit and scope of the technical solution of the present invention.
The first embodiment is as follows: as shown in fig. 1 and 2, the transmitted light spot infrared thermal imaging detection apparatus for exciting microcrack defects of a semiconductor silicon wafer by using pulsed beam-splitting laser provided in this embodiment is composed of a controller, a thermal wave signal acquisition system, a chirped pulse beam-splitting laser excitation system, and a test piece protection device, wherein:
the controller is a computer 1 embedded with a LabVIEW platform;
the control graphical interface of the computer 1 embedded with the LabVIEW is called and used by a main program VI and a sub-program VI;
the thermal wave signal acquisition system comprises a data acquisition card 3, a thermal infrared imager 23 and a micro-focus lens 22;
the linear frequency modulation pulse beam splitting laser excitation system comprises a laser driver 5, a laser transmitter 7, a reflector, a beam expander 13 and a beam splitter 15;
the test piece protection device comprises a temperature sensor 19, a seal box 12, a buzzer 21 and a single chip microcomputer 20;
the micro-focus lens 22 is arranged on an optical lens of the thermal infrared imager 23;
the sealing box 12 is a cuboid with the inner wall adhered with a reflective film, the left side surface is processed with a circular laser incident hole 11, and the front side surface is provided with a box body door 24;
the thermal infrared imager 23, the beam expander 13 and the beam splitter 15 are arranged in the sealed box 12;
the temperature sensor 19 is arranged on the inner side of the box body door 24, and the buzzer 21 and the singlechip 20 are arranged on the outer side of the box body door 24;
the reflector is composed of a first reflector 9 and a second reflector 10;
the data output end of the computer 1 embedded with the LabVIEW platform is connected with the data input end of a data acquisition card 3 through a first signal wire 2;
the data output end of the data acquisition card 3 is connected with the data input end of the laser driver 5 through a second signal line 4;
the data output end of the laser driver 5 is connected with the data input end of the laser transmitter 7 through a third signal line 6;
the single beam of laser 8 emitted by the laser emitter 7 changes the irradiation direction twice through the first reflector 9 and the second reflector 10, enters the beam expander 13 through the incident hole 11 of the seal box 12, the single beam of laser 8 is expanded into single beam expanded laser 14 through the beam expander 13, and the single beam expanded laser 14 is split into beam split laser 16 through the beam splitter 15 and is output;
a semiconductor silicon wafer test piece 17 is arranged between the beam splitter 15 and the thermal infrared imager 23;
the computer 1 embedded with the LabVIEW platform is connected with the thermal infrared imager 23 through a fifth signal line 26;
the temperature sensor 19 is processed by the single chip microcomputer 20 and then divided into two paths, one path is connected with the buzzer 21, the other path transmits data to the Zigbee transmission node, the data is transmitted to the Zigbee transmission node, the Zigbee transmission node transmits the data to the Zigbee main control node, the Zigbee main control node transmits the data to the LabVIEW platform, and the LabVIEW platform transmits the data to the computer.
The method for detecting the transmitted light spot infrared thermal imaging of the microcrack defect of the semiconductor silicon wafer excited by the pulse beam splitting laser by using the device comprises the following steps:
step 1: manufacturing a sealed box 12 (1600.0 mm multiplied by 300.0mm multiplied by 250 mm), processing a circular laser incidence hole 11 on the left side surface of the sealed box 12, opening a box body door 24 on the front side surface, and enabling the length to be approximately 1/2 of the sealed box 12;
and 2, mounting the first reflective mirror 9 and the second reflective mirror 10 on a test bench, wherein the distance between the second reflective mirror 10 and the first reflective mirror 9 is 120 ~ 150.0.0 mm, preferably 130.0mm, and the distance between the second reflective mirror 10 and the seal box 12 is 60.0 ~ 80.0.0 mm, preferably 65.0 mm.
and 4, step 4: adjusting the centers of the laser emitter 7 and the first reflective mirror 9 to be in the same straight line, the centers of the first reflective mirror 9 and the second reflective mirror 10 to be in the same straight line, and the centers of the second reflective mirror 10, the laser circular incident hole 11, the beam splitter 13, the beam splitter 15, the semiconductor silicon wafer test piece 17 and the thermal infrared imager 23 to be in the same straight line;
and 5, step 5: the control program (such as infrared thermal wave detection and excitation system signal generation software V1.0 and a data acquisition program) is compiled by LabVIEW software, and the system can run normally;
and 6, step 6: starting a computer 1 embedded with a LabVIEW platform, a thermal infrared imager 23, a micro-focus lens 22, a data acquisition card 3, a laser driver 5, a laser emitter 7, a beam expander 13, a beam splitter 15, a temperature sensor 19, a buzzer 21 and a single chip microcomputer 20;
and 7, step 7: after preheating, focusing by the thermal infrared imager 23 until the computer displays an image;
and 8, step 8: LabVIEW software is started and operated on a computer 1 embedded with a LabVIEW platform, parameters are input through an external keyboard, a linear frequency modulation excitation mode is selected for double-path scanning, and a function waveform can be modulated and a frequency modulation signal can be displayed on a graphical interface;
step 9: the laser driver 5 sends a trigger signal to trigger a laser emitter 7, the laser emitter 7 emits single laser 8, the path of the single laser 8 is changed through a first reflector 9 and a second reflector 10, the single laser 8 enters a beam expander 13 through a laser circular entrance hole 11, the beam expander 13 outputs the single expanded laser 14, the single expanded laser 14 enters a beam splitter 15 to be split into beam splitting laser 16, the pulse beam splitting laser uniformly excites a semiconductor silicon wafer test piece 17, and the thermal infrared imager 23 collects and stores real-time image data on one side of the back of the semiconductor silicon wafer test piece 17;
step 10: setting the temperature danger value to 175 ℃, when the temperature in the seal box 12 reaches the temperature danger value, the buzzer 21 controlled by the singlechip 20 gives an alarm, an alarm lamp on a display panel of LabVIEW software is lightened, and meanwhile, the alarm lamp is used as a sub VI program to trigger a main program LabVIEW to stop running, so that the semiconductor silicon wafer test piece 17 is protected from laser ablation;
and 11, step 11: and transmitting the image information acquired by the thermal infrared imager 23 to a LabVIEW platform, inputting data and images into a computer by the LabVIEW platform, and identifying the microcrack defects of the semiconductor silicon wafer of the input image by Matlab software.
The second embodiment is as follows: the embodiment provides a transmission light spot infrared thermal imaging detection example for exciting microcrack defects of a semiconductor silicon wafer by using pulse beam splitting laser.
And manufacturing a semiconductor silicon wafer microcrack defect test piece, wherein the width of a crack is 20 micrometers, and the depth is 0.2 mm. The laser is a semiconductor collimation laser with the center wavelength of 808nm @25 ℃, the power of 75W and the adjustable spot size, and is divided into 25 beams of laser by a beam splitter, and the linear frequency modulation parameters are as follows: the laser power is 300mW, the initial frequency of a linear frequency modulation signal is 0.1Hz, the termination frequency is 10Hz, and the pulse period is 10 s; recording parameters of the thermal infrared imager with the microscope lens are as follows: the sampling frequency is 50Hz, and the sampling time is 40 s. The results are shown in FIG. 3. As can be seen from fig. 4 and 5, a temperature jump occurs at the microcracks, from 42 ℃ down to 40.2 ℃ and the temperature drop is 1.8 ℃. And data acquisition is carried out on the silicon wafer by adopting a reflection method, so that the temperature is reduced from 39.95 ℃ to 38.68 ℃, and the temperature is reduced by 1.27 ℃. The result shows to adopt the utility model discloses it is effectual than reflection method to detect crazing line, discerns the semiconductor silicon chip crazing line defect more easily.
Claims (8)
1. The utility model provides a transmission light spot infrared thermal imaging detection device which characterized in that the device includes controller, heat wave signal acquisition system, chirp split beam laser excitation system, test piece protection device four bibliographic categories, wherein:
the controller is a computer embedded with a LabVIEW platform;
the thermal wave signal acquisition system comprises a data acquisition card, a thermal infrared imager and a micro-focus lens;
the linear frequency modulation pulse beam splitting laser excitation system comprises a laser driver, a laser transmitter, a reflector, a beam expander and a beam splitter;
the test piece protection device comprises a temperature sensor, a seal box, a buzzer and a single chip microcomputer;
the micro-focus lens is arranged on an optical lens of the thermal infrared imager;
a circular laser incident hole is processed on the left side surface of the sealing box, and a box body door is arranged on the front side surface of the sealing box;
the thermal infrared imager, the beam expander and the beam splitter are arranged in a sealed box;
the temperature sensor is arranged on the inner side of the box body door, and the buzzer and the single chip microcomputer are arranged on the outer side of the box body door;
the reflector is composed of a first reflector and a second reflector;
the data output end of the computer embedded with the LabVIEW platform is connected with the data input end of the data acquisition card;
the data output end of the data acquisition card is connected with the data input end of the laser driver;
the data output end of the laser driver is connected with the data input end of the laser transmitter;
laser emitted by the laser emitter is changed in laser path through the first reflector and the second reflector, enters the seal box through the circular laser incident hole of the seal box, is expanded by the beam expander and is output by the beam splitter;
the computer embedded with the LabVIEW platform is connected with the thermal infrared imager;
the temperature sensor is divided into two paths after being processed by the single chip microcomputer, one path is connected with the buzzer, and the other path is connected with a computer embedded with a LabVIEW platform.
2. The transmitted light spot infrared thermal imaging detection device of claim 1, characterized in that the sealed box is a cuboid with a reflective film adhered to an inner wall.
3. The transmitted light spot infrared thermographic inspection apparatus of claim 1 wherein the distance between said beam expander and said beam splitter is 20.0 ~ 40.0.0 mm and the distance between said beam splitter and said semiconductor silicon wafer test piece is 600.0 ~ 1000.0.0 mm.
4. The transmitted light spot infrared thermographic inspection device according to claim 3, wherein the distance between said beam expander and said beam splitter is 30.0 mm; the distance between the beam splitter and the semiconductor silicon wafer test piece was 800.0 mm.
5. The transmitted light spot infrared thermal imaging detection device of claim 1, wherein the distance between the thermal infrared imager and the back surface of the semiconductor silicon wafer test piece is 200.0 mm.
6. The transmitted light spot infrared thermographic inspection device of claim 1, wherein said cabinet door has a length that occupies 1/2 of the sealed cabinet.
7. The transmitted light spot infrared thermographic inspection device of claim 1 wherein the second mirror is spaced from the first mirror by 120 ~ 150.0.0 mm, and the second mirror is spaced from the capsule by 60.0 ~ 80.0.0 mm.
8. The transmitted light spot infrared thermographic inspection device of claim 7, wherein the second mirror is at a distance of 130.0mm from the first mirror and the second mirror is at a distance of 65.0mm from the enclosure.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201920446840.9U CN209911269U (en) | 2019-04-03 | 2019-04-03 | Transmission light spot infrared thermal imaging detection device |
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| CN201920446840.9U CN209911269U (en) | 2019-04-03 | 2019-04-03 | Transmission light spot infrared thermal imaging detection device |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109856189A (en) * | 2019-04-03 | 2019-06-07 | 黑龙江科技大学 | The transmission hot spot infrared thermal imaging detection device and method of pulse beam splitting laser excitation semi-conductor silicon chip micro-crack defect |
| CN110243863A (en) * | 2019-07-09 | 2019-09-17 | 苏交科集团股份有限公司 | A kind of the weld defect infrared intelligent detection system and method for Active spurring |
| CN111537564A (en) * | 2020-06-16 | 2020-08-14 | 中北大学 | Metal microcrack depth detection system and method based on transmission type laser thermal imaging |
-
2019
- 2019-04-03 CN CN201920446840.9U patent/CN209911269U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109856189A (en) * | 2019-04-03 | 2019-06-07 | 黑龙江科技大学 | The transmission hot spot infrared thermal imaging detection device and method of pulse beam splitting laser excitation semi-conductor silicon chip micro-crack defect |
| CN110243863A (en) * | 2019-07-09 | 2019-09-17 | 苏交科集团股份有限公司 | A kind of the weld defect infrared intelligent detection system and method for Active spurring |
| CN111537564A (en) * | 2020-06-16 | 2020-08-14 | 中北大学 | Metal microcrack depth detection system and method based on transmission type laser thermal imaging |
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Granted publication date: 20200107 |