• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The present invention relates to a chemical mechanical polishing apparatus that can more accurately detect the polishing end point in the chemical mechanical polishing process, and analyzes the polished material by spectroscopy or mass spectrometry to increase the amount of the material of the polishing finish layer, Recognition of the inflection point as the end point is characterized by detecting the polishing end point.
    公开号:KR20000044598A
    申请号:KR1019980061097
    申请日:1998-12-30
    公开日:2000-07-15
    发明作者:박형순；이상익；김창일
    申请人:김영환；현대전자산업 주식회사；
    IPC主号:
    专利说明:

    Chemical mechanical polishing equipment
    BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device, and more particularly, to a chemical mechanical polishing apparatus for detecting an end point at which polishing should be stopped in a chemical mechanical polishing process.
    In the semiconductor device manufacturing process, as the device diversifies and the degree of device integration increases, the step difference between layers increases. As part of an effort to secure the process margin by removing the step, chemical mechanical polishing (CMP) is referred to. ) Process is adopted.
    In the CMP process, a method of polishing the desired portion, that is, detecting the end point, has emerged as an important technical factor. Conventional endpoint detection methods include motor current detection and optical detection.
    The motor current test method detects the end point by measuring the current change of the driving motor that rotates the carrier holding the wafer, and the friction coefficient between the pad and the wafer surface is changed when the polishing layer is changed. The current change point is regarded as the end point by using the change of the current of the spindle drive motor to change and match the same spindle speed. The motor current test method can be applied only to a material having a significantly different friction coefficient, and thus, it is difficult to apply the same material when polishing the same material such as polishing for planarization of an inter poly oxide (IPO).
    On the other hand, the optical detection method is to detect the end point by using the difference of interference phenomena according to the thickness of the thin film by injecting light to the backside of the wafer, this method is when a plurality of layers are stacked in a multilayer structure on the wafer The disadvantage is that it is not applicable.
    As described above, when the polishing point is not accurately detected by the conventional polishing end point detection device, if polishing is not completed, the polishing process is performed again to delay the process time or when the polishing is excessive, the lower layer. There is a problem damaging it.
    The present invention devised to solve the above problems is an object of the present invention is to provide a chemical mechanical polishing apparatus that can detect the polishing endpoint more accurately in the chemical mechanical polishing process.
    1 is a cross-sectional view of a tungsten plug forming process of a semiconductor device showing an example of a polishing target layer;
    2 is a cross-sectional view of an STI device isolation film formation process of a semiconductor device showing an example of a polishing target layer;
    3 is a block diagram of a chemical mechanical polishing apparatus according to an embodiment of the present invention;
    4 is an explanatory view showing the configuration of the analyzer shown in FIG. 3 in more detail;
    * Explanation of reference numerals for the main parts of the drawings
    10: wafer 21: polishing table support
    22: polishing table 23: wafer support
    31, 32: vacuum pump 40: collector
    50: Analyzer 60: Monitor
    70: feedback system 80: motor
    51: transparent tube 54: optical lens
    55: detector S: light source
    The present invention for achieving the above object is a polishing table; A polishing table support for supporting the polishing table; A wafer support, one end of which is connected to a rear surface of the wafer and driven by a power supply to rotate the wafer; First suction means for suctioning the polished material on the polishing table; Analysis means for analyzing the polished material supplied from the first suction means; Display means for displaying an analysis result of the analysis means; Second suction means for sucking the polished material remaining in the analysis means; And a power supply means for rotating the wafer support.
    The present invention is a method for detecting the polishing endpoint by chemically analyzing the polished material in the chemical mechanical polishing process, by analyzing the material polished by spectroscopy or mass spectrometry to increase the amount of the material of the polishing layer to the end point It is characteristic to recognize and detect the polishing endpoint. That is, based on the chemical bonding state of the materials constituting the layer, the difference between the interlayer materials and the bonding force, the end point is in situ using a chemical analysis method such as spectroscopy or mass spectrometry using an infrared or ultraviolet light source. In situ) detects the end point of the chemical mechanical polishing process with a relatively simple device configuration.
    For example, in the tungsten plug forming process as shown in FIG. 1, the chemical mechanical polishing process is performed to form the tungsten film 14 over the entire structure to fill the tungsten film 14 only in the contact hole 12. In this case, the tungsten film 14 and the TiN / Ti diffusion barrier film 13, which are the polishing target film 15, should be polished to expose the oxide film 11 below. In this case, since the diffusion barrier 13 and the oxide layer 12 have different chemical configurations and bonding states, when the diffusion barrier 13 is polished and the oxide layer 12 is polished, the polishing material is analyzed in situ. Alternatively, peaks corresponding to Si and O elements are detected. Therefore, when a peak corresponding to Si-O, Si, or O element is maintained for a certain time, the oxide film 12 is completely exposed, and thus, the polishing may be stopped by recognizing this time as an end point. In FIG. 1, reference numeral 10 denotes a semiconductor substrate.
    As another example, in a shallow trench isolation (STI) process as shown in FIG. 2, an oxidation prevention defining an isolation region of a device using a pad oxide film 11 and a Si 3 N 4 film 12 on a silicon substrate 10. Pattern to expose the silicon substrate 10. After etching the exposed silicon substrate 10 to form a trench, a sacrificial oxide layer 13 is formed on the sidewalls of the trench to compensate for the damage caused by etching, and SiO 2 is formed using a high density plasma over the entire structure. A series of oxide films 14 are formed and embedded in the trenches, and then the oxide films 14 are polished until the Si 3 N 4 films 12 are exposed. In this case, the chemical composition and bonding state of the Si 3 N 4 film 12 and the SiO 2 series oxide film 14 corresponding to the polishing end point are different. Therefore, when an analysis of the abrasive material in situ there is detected a peak corresponding to Si-N or N atom, polishing proceeds, the peak corresponding to the Si-N or N elements and keep it for a certain time in accordance with the Si 3 N 4 film As it appeared, it was recognized as an end point and the grinding was stopped.
    In the chemical mechanical polishing apparatus according to the exemplary embodiment of the present invention, as shown in FIG. 3, the polishing table 22, the polishing table support 21 for supporting the polishing table 22, and one end thereof are the rear surface of the wafer 10. A wafer support 23 for rotating the wafer and driven by a motor 80, a first vacuum pump 31 for sucking the polished material on a polishing table 22 pad (not shown); 1 a collector 40 for collecting a substance sucked through the vacuum pump 31, an analyzer 50 for analyzing the polished material supplied to the collector 40, and a monitor for displaying an analysis result of the analyzer 50 ( 60), a feedback system for controlling the operation of the motor 80 by receiving the analysis result of the second vacuum pump 32 and the analyzer 50 for sucking the polished material remaining in the analyzer 50 after the analysis ( feedback system 70, power by a signal applied from the feedback system 70 It is received and a motor 80 for rotating the wafer support (23). In FIG. 3, reference numeral 24 denotes a slurry.
    The pad of the polishing table 22 is formed with a thin tube (not shown) connected to the first vacuum pump 31, so that the abrasive material between the pad of the polishing table 22 and the first vacuum pump 31. It serves as a mobile container. In addition, an amplifier (not shown) for amplifying the analysis result is connected between the analyzer 50 and the monitor 60.
    As shown in FIG. 4, the analyzer 50 moves the polished material t through the inlet 52 connected to the collector 40 and the outlet 53 connected to the second vacuum pump 32. (51), light source (S) for irradiating light to the polished material in the transparent tube (51), optical lens (54) for condensing light irradiated from the light source (S), coaxial with the optical lens (54) And a detector 55 that transmits the results to the monitor 60 and the feedback system 70.
    While the polishing is in progress, the polished material remains on the pad of the polishing table 22 together with the slurry, and is collected in the collector 40 through the first vacuum pump 31 to allow the transparent tube inlet 52 of the analyzer 50 to be polished. It is introduced into). Infrared or ultraviolet rays are incident on the polished material t in the transparent tube 51 to analyze the composition of the polished material by spectroscopy, and the inflection point that increases while the amount of the material of the polishing finish layer increases is recognized as an end point. Once the endpoint is recognized, a signal is sent to the feedback system 70 to stop polishing. The polishing stop may be performed manually without the feedback system 70.
    In the above-described embodiment of the present invention has been described as an example that the analyzer 50 is made of a spectrometer, the analyzer 50 may be made of a mass spectrometer.
    The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes can be made in the art without departing from the technical spirit of the present invention. It will be apparent to those of ordinary knowledge.
    The present invention made as described above is different from the conventional end point detection device using an optical method or an electrical method by detecting the polishing end point by analyzing the polished material by a chemical method during the chemical mechanical polishing process, the noise (noise) It can solve the problem that a signal containing a lot of) is detected. Therefore, the end point detection method according to the present invention can accurately control the process in the chemical mechanical polishing process between the layers composed of different materials to accurately process the process with one polishing without over polishing or under polishing. I can finish.
    In addition, since the end point can be detected in-situ without interrupting polishing, it is possible to reduce the process time delay due to the loss of the wafer and the regrinding process caused by the failure to detect the correct end point. However, since the process for measuring the thickness after polishing can be omitted, productivity can be improved.
    权利要求:
    Claims (6)
    [1" claim-type="Currently amended] In the chemical mechanical polishing apparatus,
    Polishing table;
    A polishing table support for supporting the polishing table;
    A wafer support, one end of which is connected to a rear surface of the wafer and driven by a power supply to rotate the wafer;
    First suction means for suctioning the polished material on the polishing table;
    Analysis means for analyzing the polished material supplied from the first suction means;
    Display means for displaying an analysis result of the analysis means;
    Second suction means for sucking the polished material remaining in the analysis means; And
    Power supply means for rotating the wafer support
    Chemical mechanical polishing apparatus comprising a.
    [2" claim-type="Currently amended] The method of claim 1,
    The chemical mechanical polishing device,
    And a feedback system having an input end coupled to the analysis means and an output end coupled to the power supply means for automatically stopping the polishing apparatus at a polishing endpoint.
    [3" claim-type="Currently amended] The method according to claim 1 or 2,
    The analysis means,
    A transparent tube for moving the polished material through an inlet connected to the suction means and an outlet connected to the second suction means;
    A light source for irradiating light to the polished material in the transparent tube;
    An optical lens for condensing light emitted from the light source; And
    And a detector disposed on the same axis as the optical lens and transmitting the result to the display means and the feedback system.
    [4" claim-type="Currently amended] The method of claim 3, wherein
    The light source is a chemical mechanical polishing apparatus, characterized in that for irradiating light of infrared or ultraviolet.
    [5" claim-type="Currently amended] The method of claim 3, wherein
    The analysis means,
    A chemical mechanical polishing apparatus comprising a mass spectrometer or a spectroscope.
    [6" claim-type="Currently amended] The method of claim 3, wherein
    And a tube acting as a transfer cylinder of the abrasive material between the polishing table and the first suction means.
    类似技术:
    公开号 | 公开日 | 专利标题
    US9799578B2|2017-10-24|Peak-based endpointing for chemical mechanical polishing
    US8679979B2|2014-03-25|Using optical metrology for within wafer feed forward process control
    JP5980843B2|2016-08-31|Polishing control method and apparatus having eddy current monitoring system and optical monitoring system
    US8460057B2|2013-06-11|Computer-implemented process control in chemical mechanical polishing
    US10493588B2|2019-12-03|Polishing apparatus and polishing method
    US6108092A|2000-08-22|Method and apparatus for detecting the endpoint in chemical-mechanical polishing of semiconductor wafers
    JP3673559B2|2005-07-20|Method for polishing a layer on a patterned semiconductor substrate
    KR100602285B1|2006-07-14|Apparatus and method for film thickness measurement integrated into a wafer load/unload unit
    US6126848A|2000-10-03|Indirect endpoint detection by chemical reaction and chemiluminescence
    DE10223945B4|2006-12-21|Method for improving the production of damascene metal structures
    US5690749A|1997-11-25|Method for removing sub-micron particles from a semiconductor wafer surface by exposing the wafer surface to clean room adhesive tape material
    KR100516405B1|2005-09-22|Apparatus for inspecting an edge exposure area of wafer
    US7862402B2|2011-01-04|Polishing apparatus and substrate processing apparatus
    US8751033B2|2014-06-10|Adaptive tracking spectrum features for endpoint detection
    US7172950B2|2007-02-06|Method for manufacturing semiconductor chip
    KR101678082B1|2016-11-21|Using spectra to determine polishing endpoints
    US5647952A|1997-07-15|Chemical/mechanical polish | endpoint method
    US9393669B2|2016-07-19|Systems and methods of processing substrates
    US6022807A|2000-02-08|Method for fabricating an integrated circuit
    US5942449A|1999-08-24|Method for removing an upper layer of material from a semiconductor wafer
    TWI521625B|2016-02-11|Detection of layer clearing using spectral monitoring
    KR100334203B1|2002-06-20|Forming a transparent window in a polishing pad for a chemical mechanical polishing apparatus
    JP5455282B2|2014-03-26|Silicon-on-insulator transfer wafer edge removal
    DE102004055233B4|2016-07-21|Method for producing a semiconductor wafer
    US6336841B1|2002-01-08|Method of CMP endpoint detection
    同族专利:
    公开号 | 公开日
    KR100543195B1|2006-04-06|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    法律状态:
    1998-12-30|Application filed by 김영환, 현대전자산업 주식회사
    1998-12-30|Priority to KR1019980061097A
    2000-07-15|Publication of KR20000044598A
    2006-04-06|Application granted
    2006-04-06|Publication of KR100543195B1
    优先权:
    申请号 | 申请日 | 专利标题
    KR1019980061097A|KR100543195B1|1998-12-30|1998-12-30|Chemical mechanical polishing equipment|
    [返回顶部]