Substrate etching method and semiconductor process equipment

Abstract

The invention discloses a substrate etching method and semiconductor process equipment, and belongs to the technical field of semiconductor processing, and the method comprises the steps: providing a to-be-etched structure which comprises a substrate, and a transfer layer and a patterned mandrel layer which are sequentially formed on the substrate; forming side walls on two sides of each core shaft of the patterned core shaft layer; removing the patterned core shaft layer; etching the transfer layer by taking the side wall as a mask to obtain a transfer pattern; etching the substrate by taking the transfer pattern as a mask; when the actual width of the mandrel is larger than the first preset width, the actual width of the side wall is smaller than the second preset width, and the width of the end, close to the substrate, of the transfer pattern is larger than the width of the end, close to the side wall, of the transfer pattern; or, when the actual width of the mandrel is smaller than the first preset width, the actual width of the side wall is larger than the second preset width, and the width of the end, close to the substrate, of the transfer pattern is smaller than the width of the end, close to the side wall, of the transfer pattern.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor processing technology, and specifically relates to a substrate etching method and semiconductor process equipment. Background Art

[0002] In the semiconductor manufacturing process, multiple exposure technology is used to achieve smaller feature size graphics. However, during the multiple exposure process, as the exposure, deposition, etching and other processes proceed, the spacing between graphics may change, resulting in inconsistent width dimensions of the final graphics.

[0003] like Figure 1 As shown, etching the patterned photoresist layer 3 can transfer the pattern to the core shaft layer 2. During this process, the pattern width of the core shaft layer 2 may differ from the predetermined width due to certain factors. For example, if the pattern width of the core shaft layer 2 is larger than the predetermined width, if a deposition layer 4 with preset parameters is still formed on the core shaft layer 2, the spacing between the side walls formed by the deposition layer 4 and the two adjacent patterns in the core shaft layer 2 will be relatively small. After removing the core shaft layer 2 and etching the substrate 1 with the side walls as a mask to transfer the pattern to the substrate 1, the first width period L1 and the second width period L2 of the two adjacent patterns in the pattern formed on the substrate 1 will be different, which will have a serious impact on the electrical properties and yield of the chip device. Summary of the Invention

[0004] The purpose of the embodiments of the present application is to provide a substrate etching method and semiconductor process equipment to solve the problem in the current etching method that if the pattern width of the core axis layer is different from the predetermined width, it will cause the period widths between the patterns formed on the substrate to be different, thereby having a serious impact on the electrical properties and yield of the chip device.

[0005] In a first aspect, an embodiment of the present application discloses a method for etching a substrate, comprising: Providing a structure to be etched, the structure to be etched comprising a substrate and a transfer layer and a patterned mandrel layer sequentially formed on the substrate; forming sidewalls on both sides of each mandrel of the patterned mandrel layer; removing the patterned mandrel layer; Using the sidewall as a mask, etching the transfer layer to obtain a transfer pattern; Using the transfer pattern as a mask, etching the substrate; Wherein, when the actual width of the mandrel is greater than the first predetermined width, the actual width of the sidewall is made smaller than the second predetermined width, and the width of the end of the transfer pattern close to the substrate is made greater than the width of the end close to the sidewall; or When the actual width of the core shaft is smaller than the first predetermined width, the actual width of the sidewall is made larger than the second predetermined width, and the width of the transfer pattern at one end close to the substrate is made smaller than the width at one end close to the sidewall.

[0006] In a second aspect, an embodiment of the present application discloses a semiconductor process device, which includes a processor, a memory, and a program or instruction stored in the memory and executable on the processor, wherein the program or instruction implements the steps of the above etching method when executed by the processor.

[0007] An embodiment of the present application discloses a method for etching a substrate, which sequentially forms a transfer layer and a patterned core shaft layer on the substrate, and forms side walls on opposite sides of each core shaft in the patterned core shaft layer, so that after removing the patterned core shaft layer, the size of the mask pattern is reduced and the number of mask patterns is doubled, and then, in the process of etching the transfer layer using the side walls as a mask, a transfer pattern with twice the number of patterns as that of the patterned core shaft layer can be formed on the transfer layer. Thereafter, in the process of etching the substrate using the transfer pattern of the transfer layer as a mask, the transfer pattern can be further transferred to the substrate, thereby achieving the purpose of reducing the critical size of the pattern formed on the substrate.

[0008] In the etching method of the present application, if the actual width of the core shaft of the patterned core shaft layer is different from its predetermined width, that is, the first predetermined width, the actual widths of the relative ends of the transfer pattern of the transfer layer can be adjusted to ultimately achieve the purpose of improving the uniformity of the periodic width of the pattern formed on the substrate.

[0009] To elaborate, when the actual width of the core shaft of the patterned core shaft layer is greater than the first predetermined width, by making the actual width of the side wall smaller than its initial design size, that is, the second predetermined width, the spacing between the two side walls located between adjacent core shafts can be appropriately increased, thereby improving the width dimension between any two adjacent side walls; at the same time, by controlling the actual width of the end of the transfer pattern of the transfer layer close to the substrate to be greater than the actual width of the end of the transfer pattern close to the side wall, when the transfer layer is used as a mask to etch the substrate, the width dimension of the pattern formed on the substrate can be increased, thereby ensuring that the uniformity of the width dimension and period width of the pattern on the substrate meets the requirements.

[0010] Alternatively, when the actual width of the core shaft is smaller than the first predetermined width, the actual width of the side wall can be controlled to be larger than the second predetermined width, and the actual width of the transfer pattern of the transfer layer close to the substrate can be controlled to be smaller than the actual width of the transfer pattern close to the side wall, so that the uniformity of the width size and period width of the pattern on the substrate can also meet the requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings: Figure 1 Schematic diagram of the etching process of the substrate in the current technology; Figure 2 A schematic diagram of the etching process of a substrate disclosed in an embodiment of the present application; Figure 3 Another schematic diagram of the etching process of the substrate disclosed in the embodiment of the present application; Figure 4 This is a flow chart of the substrate etching method disclosed in an embodiment of the present application.

[0012] Reference numerals: 1-substrate, 2-mandrel layer, 3-photoresist layer, 4-deposition layer, L1-first width period, L2-second width period, 100 - substrate, 200 - mandrel layer, 300 - photoresist layer, 400 - deposition layer, 510 - first transfer layer, 520 - second transfer layer, L3 - first width period, L4 - second width period. DETAILED DESCRIPTION

[0013] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0014] The terms "first," "second," and the like in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than that illustrated or described herein, and that the objects distinguished by "first," "second," and the like are generally of the same type, and do not limit the number of objects; for example, the first object can be one or more. In addition, the term "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects connected are in an "or" relationship.

[0015] An embodiment of the present application discloses a substrate etching method. By using this etching method, when the actual width of the pattern of the core axis layer is significantly different from the predetermined width due to certain reasons, the actual width of the pattern of the transfer layer can be controlled by controlling parameters such as the thickness parameters of the side wall and the etching conditions of the side wall, thereby making the width and period width of the pattern formed on the substrate relatively more uniform.

[0016] In detail, such as Figure 4 As shown, the substrate etching method disclosed in the embodiment of the present application includes: S1. Providing a structure to be etched, the structure to be etched comprising a substrate and a transfer layer and a patterned mandrel layer sequentially formed on the substrate; S2, forming sidewalls on both sides of each mandrel of the patterned mandrel layer; S3, removing the patterned mandrel layer; S4, using the sidewall as a mask, etching the transfer layer to obtain a transfer pattern; S5. Using the transferred pattern as a mask, the substrate is etched.

[0017] Specifically, the material of the transfer layer can be selected according to the material of the sidewalls to be formed, so that during the etching process of the transfer layer, the sidewalls can serve as a mask for the transfer layer, and the pattern of the sidewalls can be transferred to the transfer layer, thereby giving the transfer layer a transfer pattern. Of course, the materials and thicknesses of the mandrel layer, transfer layer, and sidewalls can be flexibly selected according to actual conditions.

[0018] In one specific embodiment of the present application, the mandrel layer can be formed of an amorphous silicon material, and the sidewalls can be formed of a silicon nitride material. In this case, the transfer layer can be formed solely of silicon oxide to ensure that the sidewalls can serve as a mask for the transfer layer, so that the pattern of the sidewalls can be transferred to the transfer layer during the etching process of the transfer layer. In other embodiments of the present application, the material of the transfer layer includes at least one of silicon nitride, silicon oxide, silicon oxynitride, titanium dioxide, and aluminum oxide.

[0019] More specifically, a process such as vapor deposition can be used to sequentially form a transfer layer and a mandrel layer on a substrate, and after the mandrel layer is patterned, sidewalls are formed on both sides of each mandrel of the mandrel layer. Specifically, the sidewalls can be formed by partially etching the deposition layer 400. That is, after forming the patterned mandrel layer, a deposition process can be used to form the deposition layer 400 on top of the patterned mandrel layer and the transfer layer. Thereafter, the portion of the deposition layer covering the top of the patterned mandrel layer and the top of the transfer layer can be removed by etching, leaving portions of the deposition layer deposited on opposite sides of each mandrel in the patterned mandrel layer. The aforementioned portions are the sidewalls.

[0020] In more detail, the above step S1 may include: S11, providing a substrate; S12, forming a transfer layer, a mandrel layer and a photoresist layer in sequence on the substrate; S13, patterning the photoresist layer; S14, using the photoresist layer as a mask, etching the mandrel layer to form a patterned mandrel layer; S15. Measure the actual width of the mandrels in the patterned mandrel layer.

[0021] That is, after the transfer layer and the mandrel layer 200 are sequentially formed using a deposition process, a photoresist layer 300 can be formed on the side of the mandrel layer 200 facing away from the transfer layer. Specifically, the photoresist layer 300 can be formed by spin coating or other methods. Thereafter, the photoresist layer can be patterned by exposure and development to form a patterned photoresist layer. Furthermore, the patterned photoresist layer can be used as a mask to etch the mandrel layer so that the pattern of the photoresist layer is transferred to the mandrel layer, thereby forming a patterned mandrel layer.

[0022] As described above, in the process of forming the patterned core shaft layer, the width of the patterned core shaft layer may differ from the predetermined width due to certain reasons. For this reason, in the etching method disclosed in the embodiment of the present application, after the patterned core shaft layer is formed, the actual width of the core shaft of the patterned core shaft layer needs to be measured to determine whether the actual width of the core shaft in the patterned core shaft layer meets the predetermined width.

[0023] Specifically, a scanning electron microscope can be used to measure the actual width of the core shafts in the patterned core shaft layer. In this case, the measurement cost can be reduced as much as possible while ensuring a relatively high measurement accuracy of the actual width of the core shafts in the patterned core shaft layer.

[0024] After completing the measurement of the actual width of the core shaft in the actually formed patterned core shaft layer, if the actual width of the core shaft meets the first predetermined width, the deposition layer can still be formed accordingly according to the preset parameters, and the process recipe can be controlled according to the preset parameters to use the side wall as a mask to etch the transfer layer, and finally form a pattern that meets the requirements on the substrate.

[0025] In the case that the actual width of the core shaft does not meet the first predetermined width, the process recipe can be controlled accordingly according to the specific situation of the actual width of the core shaft, and the deposition thickness of the side wall can be changed. At the same time, the etching situation of the transfer layer can be changed accordingly, so that a pattern that meets the requirements can still be formed on the substrate, that is, the width of the pattern of the substrate is equal or basically equal, and the density is the same or basically the same, thereby ensuring that the uniformity of the pattern of the substrate meets the requirements.

[0026] In detail, when the actual width of the core shaft of the patterned core shaft layer is greater than the first predetermined width, if side walls are still formed on both sides of the core shaft according to preset parameters, the spacing between the two side walls located between two adjacent core shafts will be smaller than the spacing between the two side walls located on the opposite sides of the same core shaft. In this case, if the transfer layer is directly etched using the above-mentioned side walls as a mask, there will be differences in the period widths of the two adjacent graphics on the substrate.

[0027] Therefore, in the etching method disclosed in the embodiment of the present application, for the above situation, as Figure 2 As shown, by changing the process recipe, the actual width of the sidewall spacer is controlled to be smaller than the second predetermined width. That is, if the actual width of the mandrel of the patterned mandrel layer is larger than the first predetermined width of the mandrel, the actual width of the sidewall spacer formed on opposite sides of the mandrel can be made smaller than the second predetermined width. This can compensate for the relatively small remaining width between two adjacent mandrels due to the larger mandrel width.

[0028] At the same time, since the width of the sidewall formed in the above process is smaller than the second predetermined width, in order to ensure that the transfer layer is etched using the sidewall as a mask, and the substrate is etched using the transfer layer as a mask, so that the width of the pattern finally formed on the substrate can still be comparable to the predetermined width, in an embodiment of the present application, the actual width of the end of the transfer pattern formed on the transfer layer close to the substrate is also controlled to be greater than the width of the end of the transfer pattern close to the sidewall.

[0029] More specifically, the actual width of one end of the transfer pattern of the transfer layer close to the substrate can be made less than or equal to the second predetermined width, and then, in the process of etching the substrate using the transfer layer as a mask, the width dimension of the pattern formed on the substrate can be equivalent to the second predetermined width, that is, the original width design dimension of the side wall, and the third width period L3 between two adjacent patterns in the pattern formed on the substrate 100 is ensured to be equal to the fourth width period L4 between the other two adjacent patterns, so that the uniformity of the pattern on the substrate 100 meets the requirements.

[0030] In some other embodiments, when the actual width of the core shaft of the patterned core shaft layer is smaller than the first predetermined width, if side walls are still formed on both sides of the core shaft according to preset parameters, the spacing between the two side walls between the two adjacent core shafts will be greater than the spacing between the two side walls located on the opposite sides of the same core shaft. In this case, if the above-mentioned side walls are directly used as masks, there will also be differences in the period widths of the two adjacent graphics on the substrate.

[0031] Therefore, in the etching method disclosed in the embodiment of the present application, for the above situation, as Figure 3As shown, the process recipe can also be changed accordingly to control the actual width of the sidewall spacer to be greater than the second predetermined width. That is, when the actual width of the mandrel of the patterned mandrel layer is smaller than the first predetermined width of the mandrel, the width of the sidewall spacers formed on opposite sides of the mandrel is made larger than the second predetermined width. This can compensate for the relatively large residual width between two adjacent mandrels caused by the smaller mandrel width.

[0032] At the same time, since the width of the side wall formed in the above process is greater than the second predetermined width, and in order to ensure that the width of the pattern finally formed on the substrate by using the side wall as a mask can still be comparable to the predetermined width, in an embodiment of the present application, the actual width of the end of the transfer pattern of the transfer layer close to the substrate is also controlled to be smaller than the actual width of the end of the transfer pattern away from the side wall.

[0033] More specifically, the actual width of the end of the transfer pattern of the transfer layer close to the substrate can be greater than or equal to the second predetermined width, so that in the process of etching the substrate using the transfer layer as a mask, the width of the pattern formed on the substrate can be equivalent to the second predetermined width, that is, the original width design size of the side wall, and the third width period L3 between two adjacent patterns in the pattern formed on the substrate 100 is ensured to be equal to the fourth width period L4 between the other two adjacent patterns, so that the uniformity of the pattern on the substrate 100 meets the requirements.

[0034] An embodiment of the present application discloses a method for etching a substrate, which sequentially forms a transfer layer and a patterned core shaft layer on the substrate, and forms side walls on opposite sides of each core shaft in the patterned core shaft layer, so that after removing the patterned core shaft layer, the size of the mask pattern is reduced and the number of mask patterns is doubled, and then, in the process of etching the transfer layer using the side walls as a mask, a transfer pattern with twice the number of patterns as that of the patterned core shaft layer can be formed on the transfer layer. Thereafter, in the process of etching the substrate using the transfer pattern of the transfer layer as a mask, the transfer pattern can be further transferred to the substrate, thereby achieving the purpose of reducing the critical size of the pattern formed on the substrate.

[0035] In the etching method of the present application, if the actual width of the core shaft of the patterned core shaft layer is different from its predetermined width, that is, the first predetermined width, the actual widths of the relative ends of the transfer pattern of the transfer layer can be adjusted to ultimately achieve the purpose of improving the uniformity of the periodic width of the pattern formed on the substrate.

[0036] To elaborate, when the actual width of the core shaft of the patterned core shaft layer is greater than the first predetermined width, by making the actual width of the side wall smaller than its initial design size, that is, the second predetermined width, the spacing between the two side walls located between adjacent core shafts can be appropriately increased, thereby improving the width dimension between any two adjacent side walls; at the same time, by controlling the actual width of the end of the transfer pattern of the transfer layer close to the substrate to be greater than the actual width of the end of the transfer pattern close to the side wall, when the transfer layer is used as a mask to etch the substrate, the width dimension of the pattern formed on the substrate can be increased, thereby ensuring that the uniformity of the width dimension and period width of the pattern on the substrate meets the requirements.

[0037] In some other embodiments, when the actual width of the core shaft is smaller than the first predetermined width, the actual width of the side wall can be controlled to be larger than the second predetermined width, and the actual width of the transfer pattern of the transfer layer close to the substrate can be controlled to be smaller than the actual width of the transfer pattern close to the side wall, so that the uniformity of the width size and period width of the pattern on the substrate can also meet the requirements.

[0038] As described above, the transfer layer can be formed of a single material. To reduce the difficulty of controlling the actual width of the end of the transfer layer close to the substrate, in another embodiment of the present application, the transfer layer can include a first transfer layer 510 and a second transfer layer 520. In this case, the above step S12 includes: A first transfer layer, a second transfer layer, a mandrel layer and a photoresist layer are sequentially formed on the substrate.

[0039] That is, the second transfer layer is located on the side of the first transfer layer facing away from the substrate. Of course, during the design process, it is necessary to ensure that the etching rates of the first transfer layer and the second transfer layer are different under the same etching conditions, thereby reducing the difficulty of controlling the etching process. Optionally, the first transfer layer 510 and the second transfer layer 520 are made of different materials, so that during the etching process of the second transfer layer and the first transfer layer, The etching parameters of the first transferred layer closer to the substrate can be easily changed by controlling parameters such as the type of etching gas.

[0040] More specifically, in one embodiment of the present application, one of the first transfer layer and the second transfer layer is silicon nitride, and the other is silicon oxide. These two materials have relatively high chemical stability and can form a better interface with the mandrel layer and the substrate, thereby improving the etching effect. In addition, when the first transfer layer and the second transfer layer are respectively made of the above materials, the selection of etching gas is also easier. Specifically, compared to silicon nitride, fluorine gas and its compounds etch silicon oxide faster, while compared to silicon oxide, chlorine gas and its compounds etch silicon nitride faster. Therefore, by combining different etching gases accordingly, precise etching of the first transfer layer and the second transfer layer can be achieved.

[0041] In the case where the transfer layer includes a first transfer layer and a second transfer layer, the above step S4 may specifically include: Using the sidewall as a mask, the pattern of the sidewall is transferred to the second transfer layer to form a second transfer pattern; Using the second transfer pattern as a mask, etching the first transfer layer to form a first transfer pattern; As described above, the second transfer layer is located on the side of the first transfer layer facing away from the substrate. Therefore, during the etching process, the sidewalls are used as a mask to first etch the second transfer layer to transfer the sidewall pattern to the second transfer layer, thereby patterning the second transfer layer. Subsequently, the patterned second transfer layer is used as a mask to further etch the first transfer layer to transfer the pattern of the second transfer layer to the first transfer layer, forming a patterned first transfer layer. It should be noted that the pattern formed on the second transfer layer is specifically the second transfer pattern, and the pattern formed on the first transfer layer is the first transfer pattern. The first and second transfer layers constitute the entire transfer layer, and the first and second transfer patterns constitute the entire transfer pattern. Furthermore, during the etching process of the first transfer layer, some sidewalls may remain.

[0042] Of course, when the actual width of the core shaft of the core shaft layer does not meet the first predetermined width, in order to ensure that when the first transfer layer is used as a mask and the substrate is etched, the width and density of the pattern formed on the substrate can meet the preset requirements, when the transfer layer includes the above-mentioned first transfer layer and second transfer layer, the first transfer pattern on the first transfer layer can be controlled.

[0043] Specifically, when the actual width of the mandrel is greater than the first predetermined width, the width of the first transfer pattern is greater than the width of the second transfer pattern; when the actual width of the mandrel is less than the first predetermined width, the width of the first transfer pattern is less than the width of the second transfer pattern.

[0044] When adopting the above technical solution, when the actual width of the core shaft is greater than the first predetermined width, it can be ensured that in the entire transfer layer, the width of the end of the transfer pattern as a whole structure close to the substrate is greater than the width close to the side wall; correspondingly, when the actual width of the core shaft is less than the first predetermined width, it can be ensured that in the entire transfer layer, the width of the end of the transfer pattern as a whole structure close to the substrate is less than the width close to the side wall.

[0045] Based on the above-mentioned embodiments of the present application, in the process of controlling the width of the first transfer pattern, the widths at different height positions in the first transfer pattern can be made equal or substantially equal. In order to further reduce the difficulty of controlling the structural parameters of the first transfer pattern, in another embodiment of the present application, in the process of etching the first transfer layer, the width of the end of the first transfer pattern close to the substrate can be controlled by controlling the slope angle of the first transfer pattern.

[0046] In an embodiment of the present application, the width of the first transfer pattern at the end closest to the substrate is different from the width at the end closest to the sidewall (or second transfer layer), and the sidewalls of the first transfer pattern are generally inclined, that is, the first transfer pattern has a predetermined sidewall inclination angle (i.e., a slope angle). By employing the technical solution of the present application, the width of the first transfer pattern at the end closest to the substrate is relatively easy to control. Furthermore, during the etching process, the etching parameters of the first transfer layer can be flexibly controlled based on the actual etching conditions of the first transfer layer by adjusting parameters such as the process recipe in real time. This allows for relatively higher precision in the width of the first transfer layer at the end closest to the substrate, thereby further improving substrate etching uniformity.

[0047] As described above, the width of the sidewalls and the etching rate of the transfer layer can be controlled by adjusting the process recipe. That is, in the embodiment of the present application, the actual width of the sidewalls can be made different from the second predetermined width, and the width of the transfer pattern of the transfer layer close to the substrate can be made different from the width close to the sidewall. In more detail, the process recipe can specifically include parameters such as process time and flow rate and pressure of process gas. The aforementioned parameters can more directly change the width of the formed sidewalls. In addition, when the type of process gas is different, the etching rate of the transfer layer can also be more directly changed. In more detail, in the embodiment of the present application, the purpose of controlling the width of the sidewalls and the etching speed of the transfer layer can also be achieved by changing other parameters such as RF power. Of course, when the size relationship between the actual width of the mandrel of the patterned mandrel layer and the first predetermined width is different, the specific value of the controlled process recipe must also be different.

[0048] Based on the above situation, in the embodiment of the present application, the process recipe may include at least one of RF power, process time, flow rate and pressure of process gas, and type of process gas.

[0049] As described above, the purpose of adjusting the etching rate of the transfer layer can be achieved by adjusting the process recipe. Since the adjustment accuracy required for the etching rate of the transfer layer is relatively high, in the etching method disclosed in the embodiment of the present application, the chamber pressure when etching the side walls can be made relatively low, that is, the side walls are etched under a relatively low pressure, and the transfer layer is etched using the side walls as a mask. This can make the etching rate relatively small, thereby improving the etching uniformity, which is conducive to more precise control of the etching degree of the transfer layer, and ultimately achieve the purpose of improving the etching accuracy of the patterns on the substrate and the uniformity of the period width between patterns.

[0050] To be more precise, under the first chamber pressure, the transfer layer is etched using the sidewall as a mask, and under the second chamber pressure, the substrate is etched using the transfer pattern as a mask. The first chamber pressure is lower than the second chamber pressure, ensuring that the chamber pressure when etching the sidewall is relatively small, thereby ultimately improving the etching uniformity of the substrate.

[0051] In the etching method of the substrate disclosed in the embodiment of the present application, as described above, if the actual width of the core shaft of the patterned core shaft layer is different from the first predetermined width, the width of the side wall can be adjusted, and the width dimensions of the transfer pattern in the transfer layer close to the substrate and the end close to the side wall can be controlled, so that the width of the pattern formed on the substrate meets the predetermined width and the uniformity of the period width between the patterns on the substrate meets the preset requirements.

[0052] Furthermore, in order to determine whether the above adjustment process can have a beneficial effect on the uniformity of the pattern on the substrate, in the embodiment of the present application, after the above step S5, the following steps may be further included: The actual width of the pattern in the substrate is measured. Specifically, a scanning electron microscope can be used to measure the actual width of the pattern in the substrate after etching.

[0053] Afterwards, the substrate etching method further includes: When the difference between the actual width and the standard width satisfies a first preset difference, a first standard data set is formed, wherein the first standard data set includes the actual width of the corresponding mandrel and the actual process recipe of the etching process of the sidewall; In the case of etching the structure to be etched next time, if the difference between the width of the mandrels in the patterned mandrel layer and the actual width meets the second preset difference, the process recipe is controlled to be the actual process recipe.

[0054] That is, in the embodiment of the present application, the etching process performed each time when the actual width of the core shaft of the patterned core shaft layer deviates from the first predetermined width can be verified. If, after adopting the corresponding process recipe, the actual width and uniformity of the pattern on the etched substrate meet the requirements, then the adjustment of the above process recipe is considered to be effective. For this purpose, the process recipe and the actual width of the core shaft of the patterned core shaft layer can be recorded as standard data in the subsequent etching process, so that when the structure to be etched with the same structure is etched again, if the difference between the width of the core shaft of the formed patterned core shaft layer and the actual width in the first data set meets the second preset difference, the process recipe corresponding to the actual width can be directly called, which can basically ensure that the width size of the pattern formed on the new substrate meets the requirements, and the uniformity of the width period between the patterns also meets the requirements.

[0055] Of course, there is a difference between the actual width of the core shaft of the patterned core shaft layer and the first predetermined width, and after the process recipe is adjusted accordingly, the actual width and uniformity of the pattern on the etched substrate may still not meet the requirements, then the adjustment of the above process recipe is considered to be invalid or partially invalid. In this case, when etching the same structure to be etched next time, even if the difference between the width of the core shaft of the patterned core shaft layer and the actual width meets the second preset difference, the process recipe that is the same as the actual process recipe corresponding to the aforementioned actual width in the first standard data set will no longer be used. Instead, it is necessary to adjust the process recipe corresponding to the actual width of the core shaft of the patterned core shaft layer based on the previous etching results to further optimize the etching effect and ensure that when the same structure to be etched is etched next time, if the difference between the width of the core shaft of the patterned core shaft layer and the actual width meets the second preset difference, the width and uniformity of the pattern formed on the substrate meet the requirements.

[0056] That is, if the difference between the actual width of the substrate pattern and the standard width does not satisfy the aforementioned first preset difference, and when etching the next structure to be etched with the same structure, the difference between the width of the mandrel of the patterned mandrel layer and the actual width in the first standard data set satisfies the second preset difference, then based on the deviation direction of the aforementioned difference and the actual process recipe corresponding to the actual width of the mandrel in the first standard data set, the process recipe is controlled to be adjusted accordingly. Generally speaking, if the actual width of the mandrel is not equal to the first predetermined width, and if the width uniformity and period uniformity of the substrate pattern can be reduced by positively adjusting the parameters in the process recipe, then if the difference between the actual width of the substrate pattern and the standard width still does not satisfy the first preset difference, the corresponding parameters in the process recipe can be further positively adjusted. At the same time, if further positively adjusting the corresponding parameters in the process recipe actually increases the width uniformity and period uniformity of the substrate pattern, the corresponding parameters in the process recipe can be negatively adjusted until the width uniformity and period uniformity of the substrate pattern are further reduced.

[0057] An embodiment of the present application also provides a semiconductor process device, including a processor, a memory, and a program or instruction stored in the memory and executable on the processor. When the program or instruction is executed by the processor, each process of the above-mentioned etching method embodiment is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be described here.

[0058] It should be noted that, in this article, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, it should be noted that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved. For example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0059] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.

Claims

1. A substrate etching method, characterized in that: include: Providing a structure to be etched, the structure to be etched comprising a substrate and a transfer layer and a patterned mandrel layer sequentially formed on the substrate; forming sidewalls on both sides of each mandrel of the patterned mandrel layer; removing the patterned mandrel layer; Using the sidewall as a mask, etching the transfer layer to obtain a transfer pattern; Using the transfer pattern as a mask, etching the substrate; When the actual width of the core shaft is greater than the first predetermined width, the actual width of the sidewall is made smaller than the second predetermined width, and the width of the end of the transfer pattern close to the substrate is made greater than the width of the end close to the sidewall; or, When the actual width of the core shaft is smaller than the first predetermined width, the actual width of the sidewall is made larger than the second predetermined width, and the width of the transfer pattern at one end close to the substrate is made smaller than the width at one end close to the sidewall.

2. The substrate etching method according to claim 1, characterized in that: The material of the transfer layer includes at least one of silicon nitride, silicon oxide, silicon oxynitride, titanium dioxide and aluminum oxide.

3. The substrate etching method according to claim 1, characterized in that: The transfer layer includes a first transfer layer and a second transfer layer. The second transfer layer is located on a side of the first transfer layer away from the substrate, and the first transfer layer and the second transfer layer are made of different materials.

4. The substrate etching method according to claim 3, characterized in that: The step of etching the transfer layer using the sidewall as a mask to obtain a transfer pattern comprises: Using the sidewall as a mask, transferring the pattern of the sidewall to the second transfer layer to form a second transfer pattern; Using the second transfer pattern as a mask, the first transfer layer is etched to form a first transfer pattern; wherein, when the actual width of the core shaft is greater than the first predetermined width, the width of the first transfer pattern is made greater than the width of the second transfer pattern; or, when the actual width of the core shaft is less than the first predetermined width, the width of the first transfer pattern is made less than the width of the second transfer pattern.

5. The substrate etching method according to claim 4, characterized in that: During the etching of the first transfer layer, the width of the end of the first transfer pattern close to the substrate is controlled by controlling the slope angle of the first transfer pattern.

6. The substrate etching method according to claim 1, characterized in that: By changing the process recipe, the actual width of the sidewall is made different from the second predetermined width, and the width of the transfer pattern near the substrate is made different from the width near the sidewall, wherein the process recipe includes at least one of RF power, process time, flow rate and pressure of process gas, and type of process gas.

7. The substrate etching method according to claim 1, characterized in that: The transfer layer is etched under a first chamber pressure, and the substrate is etched under a second chamber pressure, wherein the first chamber pressure is lower than the second chamber pressure.

8. The substrate etching method according to claim 1, wherein: After etching the substrate using the transfer pattern as a mask, the method further includes: measuring the actual width of the pattern in the substrate; When the difference between the actual width and the standard width satisfies a first preset difference, forming a first standard data set, the first standard data set including the corresponding actual width of the mandrel and the actual process recipe of the etching process of the sidewall spacer; In the case of etching the structure to be etched next time, if the difference between the width of the mandrels of the patterned mandrel layer and the actual width satisfies a second preset difference, the control process recipe is the actual process recipe.

9. The substrate etching method according to claim 8, characterized in that: When the difference between the actual width and the standard width does not satisfy the first preset difference, and when the structure to be etched is etched next time, if the difference between the width of the core shaft of the patterned core shaft layer and the actual width satisfies the second preset difference, then based on the deviation direction of the difference and the actual process formula, the process formula is controlled to be adjusted accordingly.

10. A semiconductor process equipment, characterized in that: The method comprises a processor, a memory, and a program or instruction stored in the memory and executable on the processor, wherein the program or instruction, when executed by the processor, implements the steps of the etching method according to any one of claims 1 to 9.

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