Presetting method, device and equipment for overlay alignment, medium and machine table

Abstract

The invention relates to the field of semiconductor overlay, in particular to an overlay alignment presetting method, device and equipment, a medium and a novel machine. Identification area images reflected by emergent light with different wavelengths corresponding to the target alignment layer are received; determining the definition corresponding to each identification area image; and determining the wavelength of the emergent light corresponding to the identification area image with the highest definition as the alignment wavelength corresponding to the target alignment layer. The characteristic that the wavelength of emergent light of a xenon lamp is continuously variable in a large range is utilized, before batch overlay is carried out, multi-wavelength emergent light testing is carried out on a to-be-tested sample through the xenon lamp, the clearest image of an identification area corresponding to reflected light is obtained, namely, the wavelength with the strongest penetrating power for the to-be-tested sample serves as the alignment wavelength, and the alignment wavelength is used as the alignment wavelength. Therefore, the clear imaging of the identification area of the target alignment layer can be realized, and the high-precision overlay of the multi-layer and high-thickness semiconductor chip can be completed.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor overlay, and particularly to a pre-adjustment method, device, equipment, medium and new machine platform for overlay alignment. Background Art

[0002] Currently, in the field of semiconductor chip manufacturing, the number of layers and complexity of advanced node products are increasing, and the requirements for wafer alignment are also getting higher. Especially in the production process of 3D memory chips, for 3D memory chips, they have multiple layers, complex structures, and many opaque structure layers need to be added inside. With the continuous improvement of technology and market demand, the thickness of the opaque material layer is getting higher and higher, resulting in that it is increasingly difficult for the wafer alignment laser to penetrate the non-transparent material to reach the layer where the identification mark is located, and the reflected identification pattern signal will also become weaker and weaker, making it difficult to support laser alignment.

[0003] The solution in the prior art is to set multiple auxiliary alignment layers. By using the auxiliary alignment layer closer to the surface, better identification reflection clarity can be achieved, so as to complete the overlay alignment. However, it should be noted that errors will gradually accumulate during the setting process of the multiple auxiliary alignment layers, resulting in a decrease in the subsequent overlay alignment accuracy.

[0004] Therefore, how to solve the problem of poor overlay alignment accuracy of semiconductor chips with multiple layers and high thickness is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a pre-adjustment method, device, equipment, medium and new machine platform for overlay alignment to solve the problem of poor overlay accuracy of semiconductor chips with multiple layers and high thickness in the prior art.

[0006] To solve the above technical problems, the present invention provides a pre-adjustment method for overlay alignment, including:

[0007] Sending a plurality of working instruction signals to a xenon lamp, so that the xenon lamp irradiates a target alignment layer of a sample to be measured with outgoing light of different wavelengths in sequence according to different working instruction signals;

[0008] Receiving identification area images reflected by the target alignment layer for outgoing light of different wavelengths;

[0009] Determining the clarity corresponding to each of the identification area images;

[0010] Determining the wavelength of the outgoing light corresponding to the identification area image with the highest clarity as the alignment wavelength corresponding to the target alignment layer.

[0011] Optionally, in the pre-adjustment method for overlay alignment, the step of sending a plurality of working instruction signals to the xenon lamp to cause the xenon lamp to irradiate the target alignment layer of the sample to be measured with outgoing light of different wavelengths in sequence according to different working instruction signals includes:

[0012] Sending a plurality of groups of working instruction signals to the xenon lamp to cause the xenon lamp to irradiate different target alignment layers in sequence according to different groups of working instruction signals; wherein, for each target alignment layer, the xenon lamp irradiates with outgoing light of different wavelengths in sequence according to a plurality of working instruction signals in the corresponding group of working instruction signals.

[0013] Correspondingly, the step of receiving the identification area images reflected by the outgoing light of different wavelengths of the target alignment layer includes:

[0014] Receiving a group of identification area images corresponding to each target alignment layer; each group of identification area images includes the identification area images reflected by the corresponding target alignment layer for outgoing light of different wavelengths.

[0015] Correspondingly, the step of determining the wavelength of the outgoing light corresponding to the identification area image with the highest clarity as the alignment wavelength corresponding to the target alignment layer includes:

[0016] Determining the wavelength of the outgoing light corresponding to the identification area image with the highest clarity in each group of identification area images as the alignment wavelength of the corresponding target alignment layer.

[0017] Optionally, in the pre-adjustment method for overlay alignment, the step of sending a plurality of groups of working instruction signals to the xenon lamp to cause the xenon lamp to irradiate different target alignment layers in sequence according to different groups of working instruction signals includes:

[0018] Receiving a plurality of target alignment information;

[0019] Determining the corresponding target sample according to the target alignment information; each target sample includes a target alignment layer.

[0020] Sending a plurality of groups of working instruction signals to the xenon lamp to cause the xenon lamp to irradiate the target alignment layers in different target samples in sequence according to different groups of working instruction signals.

[0021] Optionally, in the pre-adjustment method for overlay alignment, the step of sending a plurality of working instruction signals to the xenon lamp includes:

[0022] Sending a combined signal of a plurality of current signals and xenon pressure signals to the xenon lamp.

[0023] A pre-adjustment device for overlay alignment includes:

[0024] A transmitting module, configured to send multiple working instruction signals to a xenon lamp, so that the xenon lamp irradiates a target alignment layer of a sample to be measured with emitted light of different wavelengths in sequence according to different working instruction signals;

[0025] A receiving module, configured to receive identification area images reflected by the target alignment layer for emitted light of different wavelengths;

[0026] A sharpness module, configured to determine the sharpness corresponding to each of the identification area images;

[0027] An alignment wavelength module, configured to determine the wavelength of the emitted light corresponding to the identification area image with the highest sharpness as the alignment wavelength corresponding to the target alignment layer.

[0028] A pre-adjustment device for overlay alignment, comprising:

[0029] A memory, configured to store a computer program;

[0030] A processor, configured to implement the steps of the pre-adjustment method for overlay alignment as described in any one of the above when executing the computer program.

[0031] A computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the pre-adjustment method for overlay alignment as described in any one of the above are implemented.

[0032] A new type of machine platform, which is configured to implement the pre-adjustment method for overlay alignment as described in any one of the above, and includes a xenon lamp, a light source controller, a wafer alignment component, and a wavelength analysis component;

[0033] The light source controller controls the wavelength of the xenon lamp;

[0034] The emitted light of the xenon lamp is respectively incident on the wafer alignment component and the wavelength analysis component;

[0035] The wafer alignment component is configured to project the emitted light of different wavelengths of the xenon lamp onto the sample to be measured, and receive identification area images of the emitted light of corresponding different wavelengths reflected by the target alignment layer of the sample to be measured;

[0036] The wavelength analysis component is configured to receive the emitted light of the xenon lamp and analyze the wavelength corresponding to the emitted light.

[0037] Optionally, in the new type of machine platform, the light source controller includes a current control component and a xenon pressure control component.

[0038] Optionally, in the new type of machine platform, the wavelength analysis component includes a spectroscope, a wavelength sensor, and a sensor processing terminal;

[0039] The beam splitter is arranged at the output end of the xenon lamp and is used for splitting the output light of the xenon lamp into a first incident light that enters the wafer alignment component and a second incident light that enters the wavelength sensor;

[0040] The wavelength sensor is used to receive the second incident light and generate a wavelength signal according to the second incident light;

[0041] The sensor processing end is used to determine the wavelength of the current output light of the xenon lamp according to the wavelength signal.

[0042] The pre-adjustment method for overlay alignment provided by the present invention sends a plurality of working instruction signals to the xenon lamp, so that the xenon lamp irradiates the target alignment layer of the sample to be measured with output light of different wavelengths in sequence according to different working instruction signals; receives the identification area images reflected by the output light of different wavelengths of the target alignment layer; determines the sharpness corresponding to each identification area image; and determines the wavelength of the output light corresponding to the identification area image with the highest sharpness as the alignment wavelength corresponding to the target alignment layer. The present invention utilizes the characteristic that the output light wavelength of the xenon lamp can be continuously variable within a large range. Before batch overlay, first, on the sample to be measured, through the xenon lamp, multi-wavelength output light is tested to obtain the identification area image corresponding to the reflected light with the highest sharpness, that is, the wavelength with the strongest penetration ability for the sample to be measured, as the alignment wavelength. In subsequent mass production, for the overlay situation corresponding to the sample to be measured, directly using the alignment wavelength can achieve clear imaging of the identification area of the target alignment layer that cannot be achieved by the limited fixed wavelengths in the prior art, and complete high-precision overlay of semiconductor chips with multiple layers and high thickness. The present invention also provides a pre-adjustment device, equipment, medium and new machine platform for overlay alignment with the above beneficial effects. Description of the Drawings

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0044] Figure 1 It is a schematic flow chart of a specific implementation manner of the pre-adjustment method for overlay alignment provided by the present invention;

[0045] Figure 2 It is a schematic flow chart of another specific implementation manner of the pre-adjustment method for overlay alignment provided by the present invention;

[0046] Figure 3 It is a schematic structural diagram of a specific implementation manner of the pre-adjustment device for overlay alignment provided by the present invention;

[0047] Figure 4 Schematic diagram of a specific embodiment of the novel machine platform provided by the present invention;

[0048] Figure 5 Schematic diagram of another specific embodiment of the novel machine platform provided by the present invention;

[0049] In the figure, it includes 100 - transmission module, 200 - reception module, 300 - clarity module, 400 - alignment wavelength module, 10 - xenon lamp, 20 - light source controller, 30 - wafer alignment assembly, 40 - wavelength analysis assembly, 41 - beam splitter, 42 - wavelength sensor, 43 - sensor processor. Specific embodiment

[0050] In order to enable those skilled in the art to better understand the solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0051] The core of the present invention is to provide a pre - adjustment method for overlay alignment. The flow diagram of a specific embodiment is as Figure 1 shown, which is called Specific Embodiment 1 and includes:

[0052] S101: Send multiple working instruction signals to the xenon lamp, so that the xenon lamp irradiates the target alignment layer of the sample to be measured with outgoing light of different wavelengths in sequence according to different working instruction signals.

[0053] The working instruction signal corresponds to the outgoing light one by one. The working instruction is actually an adjustment instruction for the wavelength of the outgoing light of the xenon lamp.

[0054] Since the wavelength of the outgoing light of the xenon lamp can vary continuously within a relatively large range, using the xenon lamp as the outgoing light source of the machine platform can greatly increase the range of alternative outgoing light wavelengths, can determine the theoretically most penetrating wavelength, and achieve the best imaging effect of the identification area.

[0055] Among them, the sample to be measured should simulate the real overlay scenario, that is, the structure of the sample to be measured should be the same as the structure of the previous layer of the overlay layer to be aligned in the plan, so as to select the most accurate alignment wavelength.

[0056] As a preferred embodiment, this step includes:

[0057] Send a combined signal of multiple current signals and xenon pressure signals to the xenon lamp.

[0058] A combined signal includes the current signal and a xenon pressure signal. The current signal regulates the operating current of the xenon lamp, and the xenon pressure signal regulates the internal air pressure of the xenon lamp. In this preferred embodiment, by adjusting the operating current and internal air pressure of the xenon lamp, the emission wavelength of the xenon lamp is adjusted. Through the adjustment of the above two parameters, a smaller interval adjustment of the emission wavelength of the xenon lamp can be achieved, and finally an emission wavelength closer to the theoretically optimal transmittance can be obtained, improving the accuracy of the alignment wavelength obtained subsequently. At the same time, the adjustment of the above two parameters is convenient and fast in actual operation. Of course, the emission wavelength of the xenon lamp can also be adjusted by adjusting other parameters, and the present invention does not limit this here.

[0059] S102: Receive the identification area images reflected by the emission light of different wavelengths corresponding to the target alignment layer.

[0060] The emission light of the xenon lamp hits the target alignment layer. There are alignment marks on the target alignment layer, and the area where the marks are located is the identification area. Of course, there is some emission light with insufficient penetration power, and no reflected identification area image will be formed at all.

[0061] It should be noted that in actual operation, one emission light should be emitted, one identification area image should be received, then the emission light of the next wavelength should be emitted, and then one identification area image should be received, rather than emitting all the emission lights first and then receiving all the identification area images uniformly.

[0062] S103: Determine the clarity corresponding to each of the identification area images.

[0063] Perform clarity calculation on the identification area images. The specific method of clarity calculation can be selected according to actual needs, and the present invention does not limit this here.

[0064] S104: Determine the wavelength of the emission light corresponding to the identification area image with the highest clarity as the alignment wavelength corresponding to the target alignment layer.

[0065] The present invention truly simulates the situation of the previous layer of the layer to be etched, and tests the penetration power of light of various wavelengths on the previous layer structure. Finally, the alignment wavelength with the best penetration power is obtained, ensuring that in mass production, clear images of the identification areas of the target alignment layers corresponding to the layers to be etched can be obtained using the alignment wavelength, realizing direct alignment, and greatly improving the accuracy of etching alignment.

[0066] The pre - adjustment method for overlay alignment provided by the present invention sends multiple working instruction signals to a xenon lamp, so that the xenon lamp irradiates the target alignment layer of the sample to be measured with outgoing light of different wavelengths in sequence according to different working instruction signals; receives the identification area images reflected by the target alignment layer corresponding to the outgoing light of different wavelengths; determines the clarity corresponding to each of the identification area images; and determines the wavelength of the outgoing light corresponding to the identification area image with the highest clarity as the alignment wavelength corresponding to the target alignment layer. By utilizing the characteristic that the wavelength of the outgoing light of the xenon lamp is continuously variable within a large range, before batch overlay, the multi - wavelength outgoing light test is first carried out on the sample to be measured through the xenon lamp, and the wavelength with the clearest identification area image corresponding to the reflected light, that is, the wavelength with the strongest penetration ability for the sample to be measured, is used as the alignment wavelength. In subsequent mass production, for the overlay situation corresponding to the sample to be measured, directly adopting the alignment wavelength can achieve clear imaging of the identification area of the target alignment layer that cannot be achieved by the limited fixed wavelengths in the prior art, and complete the high - precision overlay of semiconductor chips with multiple layers and high thickness.

[0067] On the basis of the first specific embodiment, further limit the number of the target alignment layers to obtain the second specific embodiment, and the corresponding flow schematic diagram is as Figure 2 shown, including:

[0068] S201: Send multiple groups of working instruction signals to the xenon lamp, so that the xenon lamp irradiates different target alignment layers in sequence according to different groups of working instruction signals; wherein, for each target alignment layer, the xenon lamp irradiates with outgoing light of different wavelengths in sequence according to multiple working instruction signals in the corresponding group of working instruction signals.

[0069] When testing different target alignment layers, outgoing light of different wavelengths can be used, that is, the wavelengths and quantities of the outgoing light included in each group of working instruction signals can be different and can be set according to actual situations.

[0070] S202: Receive the groups of identification area images corresponding to each of the target alignment layers; each group of identification area images includes the identification area images reflected by the corresponding target alignment layer for the outgoing light of different wavelengths.

[0071] S203: Determine the clarity corresponding to each of the identification area images.

[0072] S204: Determine the wavelength of the outgoing light corresponding to the identification area image with the highest clarity in each group of identification area images as the alignment wavelength of the corresponding target alignment layer.

[0073] Since the target alignment layers corresponding to each group of working instruction signal groups are different, there is no comparability in the clarity of different groups of identification area images. Only the clearest identification area image within the same group is obtained, and the wavelength of the corresponding outgoing light is set as the wavelength of the laser used for the corresponding target alignment layer in mass production.

[0074] The difference between this specific embodiment and the above specific embodiment is that there are multiple said target alignment layers in this specific embodiment, and the remaining steps are the same as those in the above specific embodiment, so they will not be elaborated here.

[0075] In actual production, there may be multiple types of overlay layers, and the overlay references of different types of overlay layers, that is, the objects to be aligned (i.e., the said target alignment layers), are different. In order to achieve high-precision direct alignment, the present invention prepares respective corresponding laser wavelengths with the best penetrability for each target alignment layer. This preferred embodiment greatly expands the applicable range of the pre-adjustment method for the overlay alignment, and at the same time improves the overlay alignment accuracy under complex production conditions in subsequent mass production.

[0076] Furthermore, the step of sending multiple groups of working instruction signals to the xenon lamp to make the xenon lamp irradiate different target alignment layers in sequence according to different groups of working instruction signals includes:

[0077] A1: Receive multiple target alignment information.

[0078] The target alignment information includes information on all structures between the target alignment layer and the current overlay layer in actual production.

[0079] A2: Determine the corresponding target samples according to the target alignment information; each said target sample includes a target alignment layer.

[0080] According to the target alignment information, the information on all structures that the outgoing light of the xenon lamp needs to penetrate can be obtained, and the structure of the corresponding target sample itself is the same as the structure information included in the target alignment information, further ensuring the accuracy of the alignment wavelength obtained subsequently.

[0081] A3: Send multiple groups of working instruction signals to the xenon lamp to make the xenon lamp irradiate the target alignment layers in different target samples in sequence according to different groups of working instruction signals.

[0082] Continuing from the previous text, since one lithography current layer can only correspond to one target alignment layer, and the pre-layer structures between different lithography current layers and their corresponding target alignment layers must be different. Therefore, in this preferred embodiment, for different target alignment layers, multiple pre-layer structure models of the lithography current layer with the target alignment layer as the lithography reference are prepared to further improve the accuracy of the final obtained alignment wavelength, that is, a better alignment effect can be obtained in subsequent mass production.

[0083] Next, the pre-adjustment device for lithography alignment provided by the embodiments of the present invention will be introduced. The pre-adjustment device for lithography alignment described below can be correspondingly referred to with the pre-adjustment method for lithography alignment described above.

[0084] Figure 3 It is a structural block diagram of the pre-adjustment device for lithography alignment provided by the embodiments of the present invention, which is called the third specific embodiment. Refer to Figure 3 The pre-adjustment device for lithography alignment may include:

[0085] A sending module 100, configured to send a plurality of working instruction signals to a xenon lamp, so that the xenon lamp irradiates the target alignment layer of the sample to be measured with outgoing light of different wavelengths in sequence according to different working instruction signals;

[0086] A receiving module 200, configured to receive the identification area images reflected by the outgoing light of different wavelengths corresponding to the target alignment layer;

[0087] A clarity module 300, configured to determine the clarity corresponding to each of the identification area images;

[0088] An alignment wavelength module 400, configured to determine the wavelength of the outgoing light corresponding to the identification area image with the highest clarity as the alignment wavelength corresponding to the target alignment layer.

[0089] As a preferred embodiment, the sending module 100 includes:

[0090] A plurality of sending units, configured to send a plurality of groups of working instruction signals to a xenon lamp, so that the xenon lamp irradiates different target alignment layers in sequence according to different groups of working instruction signals; wherein, for each target alignment layer, the xenon lamp irradiates with outgoing light of different wavelengths in sequence according to a plurality of working instruction signals in the corresponding group of working instruction signals;

[0091] Correspondingly, the receiving module 200 includes:

[0092] A plurality of receiving units, configured to receive groups of identification area images corresponding to each of the target alignment layers; each group of identification area images includes identification area images reflected by the corresponding target alignment layer for outgoing light of different wavelengths;

[0093] Correspondingly, the alignment wavelength module 400 includes:

[0094] A plurality of alignment units for determining the wavelength of the emitted light corresponding to the identification area image with the highest clarity in each of the identification area image groups as the alignment wavelength of the corresponding target alignment layer.

[0095] As a preferred embodiment, the sending module 100 includes:

[0096] A multi-target receiving unit for receiving a plurality of target alignment information;

[0097] A multi-sample unit for determining corresponding target samples according to the target alignment information; each of the target samples includes a target alignment layer;

[0098] A multi-sending unit for sending a plurality of working instruction signal groups to the xenon lamp, so that the xenon lamp irradiates the target alignment layer in different target samples in sequence according to different working instruction signal groups.

[0099] As a preferred embodiment, the sending module 100 includes:

[0100] A current-pressure sending unit for sending a combined signal of a plurality of current signals and xenon pressure signals to the xenon lamp.

[0101] The pre-adjustment device for overlay alignment provided by the present invention, through the sending module 100, is used to send a plurality of working instruction signals to the xenon lamp, so that the xenon lamp irradiates the target alignment layer of the sample to be measured with emitted light of different wavelengths in sequence according to different working instruction signals; the receiving module 200 is used to receive the identification area images reflected by the emitted light of different wavelengths corresponding to the target alignment layer; the clarity module 300 is used to determine the clarity corresponding to each of the identification area images; the alignment wavelength module 400 is used to determine the wavelength of the emitted light corresponding to the identification area image with the highest clarity as the alignment wavelength corresponding to the target alignment layer. The present invention utilizes the characteristic that the wavelength of the emitted light of the xenon lamp is continuously variable within a large range. Before batch overlay, first, on the sample to be measured, through the xenon lamp, test the emitted light of multiple wavelengths, and obtain the wavelength at which the identification area image corresponding to the reflected light is the clearest, that is, the wavelength with the strongest penetration ability for the sample to be measured, as the alignment wavelength. In subsequent mass production, for the overlay situation corresponding to the sample to be measured, directly adopt the alignment wavelength, and it is possible to achieve clear imaging of the identification area of the target alignment layer that cannot be achieved by the limited fixed wavelengths in the prior art, and complete the high-precision overlay of semiconductor chips with multiple layers and high thickness.

[0102] The pre-adjustment device for overlay alignment in this embodiment is used to implement the aforementioned pre-adjustment method for overlay alignment. Therefore, the specific implementation manners in the pre-adjustment device for overlay alignment can be seen in the embodiment part of the pre-adjustment method for overlay alignment in the previous text. For example, the sending module 100, the receiving module 200, the clarity module 300, and the alignment wavelength module 400 are respectively used to implement steps S101, S102, S103, and S104 in the above-mentioned pre-adjustment method for overlay alignment. Therefore, the specific implementation manners can refer to the descriptions of the corresponding various part embodiments and will not be elaborated here.

[0103] The present invention also provides a pre-adjustment device for overlay alignment, including:

[0104] A memory for storing a computer program;

[0105] A processor for implementing the steps of the pre-adjustment method for overlay alignment as described in any one of the above when executing the computer program. The pre-adjustment method for overlay alignment provided by the present invention sends a plurality of working instruction signals to a xenon lamp, so that the xenon lamp irradiates a target alignment layer of a sample to be measured with emitted light of different wavelengths in sequence according to different working instruction signals; receives the identification area images reflected by the target alignment layer corresponding to the emitted light of different wavelengths; determines the clarity corresponding to each of the identification area images; and determines the wavelength of the emitted light corresponding to the identification area image with the highest clarity as the alignment wavelength corresponding to the target alignment layer. By utilizing the characteristic that the wavelength of the emitted light of the xenon lamp is continuously variable within a large range, before batch overlay, the emitted light of multiple wavelengths is first tested on the sample to be measured through the xenon lamp, and the wavelength corresponding to the identification area image with the clearest reflected light, that is, the wavelength with the strongest penetration ability for the sample to be measured, is used as the alignment wavelength. In subsequent mass production, for the overlay situation corresponding to the sample to be measured, directly using the alignment wavelength can achieve clear imaging of the identification area of the target alignment layer that cannot be achieved by the limited fixed wavelengths in the prior art, and complete high-precision overlay of semiconductor chips with multiple layers and high thickness.

[0106] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the pre-adjustment method for overlay alignment as described in any one of the above are implemented. The pre-adjustment method for overlay alignment provided by the present invention sends a plurality of working instruction signals to a xenon lamp, so that the xenon lamp irradiates a target alignment layer of a sample to be measured with emitted light of different wavelengths in sequence according to different working instruction signals; receives the identification area images reflected by the target alignment layer corresponding to the emitted light of different wavelengths; determines the clarity corresponding to each of the identification area images; and determines the wavelength of the emitted light corresponding to the identification area image with the highest clarity as the alignment wavelength corresponding to the target alignment layer. By utilizing the characteristic that the wavelength of the emitted light of the xenon lamp is continuously variable within a large range, before batch overlay, the present invention first performs tests on the sample to be measured with emitted light of multiple wavelengths through the xenon lamp, obtains the wavelength at which the identification area image corresponding to the reflected light is the clearest, that is, the wavelength with the strongest penetration ability for the sample to be measured, as the alignment wavelength. In subsequent mass production, for the overlay situation corresponding to the sample to be measured, directly adopting the alignment wavelength can achieve clear imaging of the identification area of the target alignment layer that cannot be achieved by the limited fixed wavelengths in the prior art, and complete high-precision overlay of semiconductor chips with multiple layers and high thicknesses.

[0107] The present invention also provides a new type of machine tool. The structural schematic diagram of a specific embodiment thereof is as Figure 4 shown, which is called Embodiment 4. The new type of machine tool is used to implement the pre-adjustment method for overlay alignment as described in any one of the above, and includes a xenon lamp 10, a light source controller 20, a wafer alignment component 30, and a wavelength analysis component 40;

[0108] The light source controller 20 controls the wavelength of the xenon lamp 10;

[0109] The emitted light of the xenon lamp 10 is respectively incident on the wafer alignment component 30 and the wavelength analysis component 40;

[0110] The wafer alignment component 30 is used to project the emitted light of different wavelengths of the xenon lamp 10 onto the sample to be measured, and receive the identification area images corresponding to the emitted light of different wavelengths reflected by the target alignment layer of the sample to be measured;

[0111] The wavelength analysis component 40 is used to receive the emitted light of the xenon lamp 10 and analyze the wavelength corresponding to the emitted light.

[0112] The new type of machine tool provided by the present invention is used to implement the pre-adjustment method for overlay alignment described in any one of the above in the foregoing. Since the machine tool is applied to the lithography process, various technical details can refer to the description of the pre-adjustment method for overlay alignment in the foregoing, and will not be elaborated here.

[0113] It should be noted that the method of "determining the clarity corresponding to each of the identification area images; and determining the wavelength of the emitted light corresponding to the identification area image with the highest clarity as the alignment wavelength corresponding to the target alignment layer" in the pre-adjustment method of overlay alignment described in the foregoing can be undertaken by the wafer alignment component 30 in this specific embodiment, or can be completed by setting up another processing terminal. The present invention does not make any limitation in this regard.

[0114] As a preferred embodiment, the light source controller 20 includes a current control component and a xenon pressure control component. By adjusting the working current and the internal air pressure of the xenon lamp 10, the adjustment of the wavelength of the emitted light of the xenon lamp 10 is realized. Through the adjustment of the above two parameters, a smaller interval adjustment of the wavelength of the emitted light of the xenon lamp 10 can be achieved, and finally the wavelength of the emitted light closer to the theoretically optimal transmittance can be obtained, improving the accuracy of the subsequent obtained alignment wavelength. At the same time, the adjustment of the above two parameters is convenient and fast in actual operation. Of course, the wavelength of the emitted light of the xenon lamp 10 can also be adjusted by adjusting other parameters. The present invention does not make any limitation in this regard.

[0115] As a preferred embodiment, the wavelength analysis component 40 includes a spectroscope 41, a wavelength sensor 42, and a sensor processing terminal 43;

[0116] The spectroscope 41 is arranged at the emission end of the xenon lamp 10 and is used for splitting the emitted light of the xenon lamp 10 into a first incident light that enters the wafer alignment component 30 and a second incident light that enters the wavelength sensor 42;

[0117] The wavelength sensor 42 is used for receiving the second incident light and generating a wavelength signal according to the second incident light;

[0118] The sensor processing terminal 43 is used for determining the wavelength of the currently emitted light of the xenon lamp 10 according to the wavelength signal.

[0119] Please refer to Figure 5 , since the xenon lamp 10 itself cannot monitor the wavelength of the light it emits, therefore, in the present invention, a wavelength analysis component 40 is provided to help analyze the wavelength of the emitted light of the xenon lamp 10. The wavelength analysis component 40 adopted in this preferred embodiment has a simple structure, occupies a small space, and has little influence on the light input amount of the wafer alignment component 30 through the setting of the splitting ratio of the spectroscope 41. Of course, other forms of the wafer alignment component 30 can also be adopted. The present invention does not make any limitation in this regard.

[0120] In this specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For the relevant parts, reference can be made to the description in the method section.

[0121] It should be noted that in this specification, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0122] Those skilled in the art can further realize that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the components and steps of the examples have been generally described according to their functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Skilled professionals can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0123] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be directly implemented by hardware, software modules executed by a processor, or a combination of the two. The software modules can be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0124] The above has introduced in detail the pre-adjustment method, device, equipment, medium and new machine platform for overlay alignment provided by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A pre-adjustment method for overlay alignment, characterized in that: include: Sending a plurality of working instruction signals to the xenon lamp, so that the xenon lamp sequentially irradiates the target alignment layer of the sample to be tested with output light of different wavelengths according to different working instruction signals; receiving a marking area image reflected by the target alignment layer corresponding to the outgoing light of different wavelengths; Determine the clarity corresponding to each of the identification area images; The wavelength of the outgoing light corresponding to the identification area image with the highest definition is determined as the alignment wavelength corresponding to the target alignment layer.

2. The pre-adjustment method for overlay alignment according to claim 1, characterized in that: The sending of multiple working instruction signals to the xenon lamp so that the xenon lamp sequentially irradiates the target alignment layer of the sample to be tested with emitted light of different wavelengths according to different working instruction signals comprises: Sending a plurality of work instruction signal groups to the xenon lamp, so that the xenon lamp sequentially irradiates different target alignment layers according to different work instruction signal groups; wherein, for each target alignment layer, the xenon lamp sequentially irradiates with output light of different wavelengths according to a plurality of work instruction signals in the corresponding work instruction signal group; Correspondingly, the receiving of the marking area image reflected by the outgoing light of the target alignment layer corresponding to different wavelengths includes: receiving a marking area image group corresponding to each of the target alignment layers; each of the marking area image groups includes a marking area image of the corresponding target alignment layer reflecting the outgoing light of different wavelengths; Correspondingly, determining the wavelength of the outgoing light corresponding to the identification area image with the highest definition as the alignment wavelength corresponding to the target alignment layer includes: The wavelength of the outgoing light corresponding to the marking area image with the highest definition in each of the marking area image groups is determined as the alignment wavelength of the corresponding target alignment layer.

3. The pre-adjustment method for overlay alignment according to claim 2, characterized in that: The sending of a plurality of work instruction signal groups to the xenon lamp so that the xenon lamp sequentially irradiates different target alignment layers according to different work instruction signal groups comprises: receiving a plurality of target alignment information; Determine a corresponding target sample according to the target alignment information; each of the target samples includes a target alignment layer; A plurality of work instruction signal groups are sent to the xenon lamp, so that the xenon lamp sequentially irradiates the target alignment layers in different target samples according to different work instruction signal groups.

4. The pre-adjustment method for overlay alignment according to claim 1, characterized in that: The sending of multiple working instruction signals to the xenon lamp comprises: A combination signal of multiple current signals and xenon pressure signals is sent to the xenon lamp.

5. A pre-adjustment device for overlay alignment, characterized in that: include: A sending module, used for sending a plurality of working instruction signals to the xenon lamp, so that the xenon lamp sequentially irradiates the target alignment layer of the sample to be tested with output light of different wavelengths according to different working instruction signals; A receiving module, used for receiving the marking area image reflected by the outgoing light of the target alignment layer corresponding to different wavelengths; A clarity module, used to determine the clarity corresponding to each of the identification area images; The alignment wavelength module is used to determine the wavelength of the outgoing light corresponding to the identification area image with the highest definition as the alignment wavelength corresponding to the target alignment layer.

6. A pre-adjustment device for overlay alignment, characterized in that: include: Memory for storing computer programs; A processor, configured to implement the steps of the pre-adjustment method for overlay alignment as claimed in any one of claims 1 to 4 when executing the computer program.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the pre-adjustment method for overlay alignment as claimed in any one of claims 1 to 4 are implemented.

8. A new type of machine, characterized in that: The novel machine is used to implement the pre-adjustment method of overlay alignment as claimed in any one of claims 1 to 4, comprising a xenon lamp, a light source controller, a wafer alignment component and a wavelength analysis component; The light source controller controls the wavelength of the xenon lamp; The output light of the xenon lamp is respectively incident on the wafer alignment component and the wavelength analysis component; The wafer alignment assembly is used to project the emitted light of different wavelengths of the xenon lamp onto the sample to be tested, and receive the marking area image corresponding to the emitted light of different wavelengths reflected by the target alignment layer of the sample to be tested; The wavelength analysis component is used to receive the output light of the xenon lamp and analyze the wavelength corresponding to the output light.

9. The novel machine as claimed in claim 8, characterized in that: The light source controller includes a current control component and a xenon pressure control component.

10. The novel machine according to claim 8, characterized in that: The wavelength analysis component includes a spectrometer, a wavelength sensor and a sensor processing end; The beam splitter is disposed at the exit end of the xenon lamp, and is used to split the exit light of the xenon lamp into a first incident light incident on the wafer alignment assembly and a second incident light incident on the wavelength sensor; The wavelength sensor is used to receive the second incident light and generate a wavelength signal according to the second incident light; The sensor processing end is used to determine the wavelength of the current output light of the xenon lamp according to the wavelength signal.

Images