TW202318096A - Inspection method and inspection platform for lithography - Google Patents

Abstract

An inspection method and an inspection platform for lithography are adapted for inspecting a light source that is configured to form an illuminated area on a surface of a substrate, wherein the inspection method includes the following steps: placing at least one inspection component on the surface of the substrate, causing the at least one inspection component to have a relative movement and a relative speed in a direction with respect to the illuminated area so as to make the at least one inspection component pass through the illuminated area, inspecting the photon power of incident light in the illuminated area by the at least one inspection component, and determining optical parameters of the light source such as light intensity and radiation dose provided within the illuminated area according to the photon power and the relative speed.

Description

Detection method and detection platform for lithography process

The present invention relates to a detection method, in particular to a detection method and a detection platform for lithography process.

Lithography, a technique for forming desired patterns on a target substrate, is known to be widely used in the manufacture of integrated circuits (ICs). Specifically, in the above application, the radiation of a specific beam can be used to reduce and focus the circuit pattern etched on the reticle through the optical system to the wafer (wafer), thereby transferring the defined pattern to the wafer. on the circular target area.

In recent years, with breakthroughs in related technologies, extreme ultraviolet (EUV) light has been used as the light source of lithography process. Since EUV is suitable for exposing more complex and fine circuit patterns, it drives nanotechnology to be more advanced. Push forward.

However, due to the high technical threshold of EUV and the particularity of its exposure mechanism, semiconductor chip manufacturers can only select the light source intensity and wavelength of EUV equipment according to the control options provided by EUV lithography equipment suppliers, and they are still unable to accurately grasp EUV equipment. The actual parameter values of the light source during the lithography process, such as intensity, wavelength or radiation dose, or the actual parameter values of other processes (such as temperature, pressure, particle type, etc.) cannot be known. As a result, semiconductor chip manufacturers cannot grasp the actual process parameters in real time, so that they cannot independently and effectively improve or control the process.

The invention provides a detection method and a detection platform, which can enter the lithography equipment to measure the actual optical parameters, so as to solve the related problems caused by the current inability to grasp the actual lithography process parameters.

A detection method disclosed according to an embodiment of the present invention is suitable for detecting a light source used for a substrate. The light source is suitable for forming an irradiation area on a surface of the substrate. The detection method includes the following steps: placing at least one detection element on The surface of the substrate; make the detection element produce a relative displacement and a relative speed with the irradiation area in one direction, so that the detection element passes through the irradiation area, wherein the size of the irradiation area in the direction is much smaller than the size of the detection element in the direction; make the detection During the process of relative displacement, the element detects the optical power of the incident light in the irradiation area; and determines the optical parameters of the light source according to the detected optical power and relative speed.

A detection platform disclosed according to an embodiment of the present invention is suitable for detecting a light source used for a substrate. The light source is suitable for forming an irradiation area on a surface of the substrate. The detection platform includes at least one detection element and a controller. The detection element is adapted to be arranged on the surface of the substrate to produce a relative displacement and a relative speed with the substrate in a direction and the irradiation area and detect the light power of the incident light in the irradiation area. The controller is electrically connected to the detection element to determine the optical parameters of the light source according to the optical power and relative speed obtained by the detection element.

According to the detection method and detection platform for the lithography process disclosed in the foregoing embodiments of the present invention, since the detection element of the detection platform uses the substrate as a carrier, it can enter the lithography equipment with the substrate to measure in real time and accurately , Record or analyze the parameters related to the light source (such as light intensity, wavelength, radiation dose, etc.) during the lithography process, which helps to improve the autonomy of the process control. Accordingly, it is beneficial for the user side to improve the stability of the in-process, thereby helping to improve the yield rate.

The following will provide sufficient detailed description with one or more embodiments shown in the accompanying drawings, so that those skilled in the art can thoroughly understand and implement the present invention. However, it should be understood that the following description is not intended to limit the present invention to some specific embodiments. On the contrary, it is intended to cover alternatives, modifications, and equivalents within the spirit and scope of the various embodiments as defined by the claims.

Words such as "substantially", "about" and "substantially" may be used in the following text to describe the reasonable or acceptable amount of deviation that may exist in the modified situation or event, but the expected result can still be achieved . Hereinafter, "at least one" may also be used to describe the quantity of the described object, but unless otherwise explicitly stated, it should not be limited to the situation where the quantity is "only one". The term "and/or" may also be used below, which should be understood as including any one and all combinations of one or more of the listed items. Terms such as "connection", "installation", "fixation" and "assembly" may also be used below regarding the relative positional relationship of multiple described objects, but unless otherwise expressly stated, they should not be limited to the description objects to directly "Connecting", "setting", "fixing" or "assembling" to another described object without an intermediary can be understood as a situation where one or more intermediaries can be included between the described objects.

In addition, according to the field of the present invention, similar terms such as "radiation", "irradiation", and "exposure" may be used hereinafter to generally refer to the light beam (or "incident light) emitted by the light source during the lithography process. ”) to the substrate (eg, wafer), but the present invention is not limited by these terms.

The present invention proposes some exemplary detection methods and detection platforms that can be used in lithography. In general, please refer to FIG. 1, one exemplary embodiment of the present invention provides a detection platform 1a, which may have at least one detection element 10 (or called "sensor (sensor)"), which may be but not limited to Any suitable electronic component that is or at least has the function of converting an optical signal into an electrical signal. The detection platform 1a can be integrated on a substrate Wc. Specifically, the detection platform 1a can be placed or fixed on a specific area on the substrate Wc in any suitable manner. More specifically, the detection platform 1a can be carried on the substrate Wc in a region predetermined to be irradiated with light during the lithography process. The substrate Wc can be carried on a mobile platform (platform) T in a lithography equipment (not shown). In this way, the detection platform 1a can use the substrate Wc as a carrier. When the moving platform T drives the substrate Wc, the detection platform 1a can enter the lithography equipment together with the substrate Wc, so that the detection element 10 of the detection platform 1a It is possible to measure, record, and analyze light-related parameters in the lithography process environment in real time.

It is supplemented that the substrate Wc may be, but not limited to, a silicon wafer, a glass wafer, a thinned wafer or an etched wafer, but the present invention is not limited thereto. The mobile platform T can be, but not limited to, a stepper commonly used in lithography equipment, which can make the substrate Wc and the detection platform 1a on it move relative to the light source used in the lithography process, but the present invention It is not limited to this. In addition, the light source L shown in the figure is a light source for illuminating or radiating the substrate Wc in the lithography process, and may have, but is not limited to, a wavelength of 365 nm, 248 nm, 193 nm, 157 nm or 13.5 nm.

In addition, optionally, the detection platform 1a may further include a carrier board P, a controller DC, a charging unit C, and at least one power supply unit B based on some requirements. The carrying board P can be, but not limited to, any suitable circuit board or board. The controller DC, the charging unit C, the power supply unit B, and the aforementioned detection element 10 can all be disposed on or electrically connected to the carrying board P. The controller DC can be, but not limited to, any suitable digital signal controller (DSP controller), which can be used as a microcontroller suitable for digital signal processing. For example, the controller DC can be used to process, calculate or analyze the electrical signal converted by the detection element 10 from the light beam (or "incident light") received from the light source L, and can also control the detection element 10 according to instructions or settings. The manner or mode of receiving or responding to incident light. The charging unit C may be, but not limited to, any charging device capable of wireless or wired charging, and is suitable for supplying power to the power supply unit B. The power supply unit B can be, but is not limited to, any suitable battery, which is suitable for storing and providing the electric energy required for the operation of the detection platform 1a. In addition, optionally, based on other requirements such as information transmission, analysis, data calculation and recording, the detection platform 1a may be equipped with memory or related electronic components (not shown) that support wireless/wired transmission or reading of instructions or data. ).

Herein, please refer to FIG. 2 in conjunction with FIG. 1 to illustrate the operation steps of measuring the optical parameters of the lithography process by using the detection platform 1a. First, in the step S01 of placing the detection platform 1a, the detection platform 1a can be placed on or on the surface of the substrate Wc, whereby the detection platform 1a can be placed on the desired detection platform with the aforementioned substrate Wc as a carrier The mobile platform in the lithography equipment (such as the aforementioned mobile platform T). Next, in the step S02 of moving the detection platform 1a, the detection platform 1a can be transported together with the substrate Wc into the predetermined exposure area of the substrate Wc in the lithography equipment as the moving platform T is driven. Then or at the same time, in the step S03 of performing the lithography process, the light source of the lithography equipment (such as the aforementioned light source L) can irradiate (radiate) the area to be exposed, so that the detection platform 1a is aligned with the light source L in a specific direction. The irradiated range of the incident light (the irradiated area L' as shown in the figure) produces a relative movement and a relative speed. Then or at the same time, in the step S04 of measuring the incident light, since the moving path of the detection platform 1a is the moving path of the moving platform T, the detection platform 1a can make its detection element 10 pass the light source L along with the moving platform T. The irradiated area L' can measure the optical parameters of the actual incident light in real time. Next, in step S05 of the detection platform 1a leaving the exposure area, the detection platform 1a will continue to leave the irradiation area L' of the light source L along the moving path along with the driving of the moving platform T. Next, in the step S06 of taking out the detection platform 1a, for example, the substrate Wc can be taken out from the mobile platform T, so as to take out the detection platform 1a together, and the detection platform 1a after measuring the optical parameters can then perform the required subsequent operations. Data transmission, processing, calculation and analysis.

It can be seen from this that at least through the above-mentioned operation steps, the detection platform 1a can actually measure and record the relevant light parameters used to radiate the substrate Wc, so that the subsequent detection platform 1a or has wired/wireless communication with the detection platform 1a The connected external computer or control center can perform the required data processing, calculation and analysis based on the collected information, so as to obtain the actual optical parameters such as light intensity, wavelength or radiation dose of the light source L during the aforementioned operation. Here, those skilled in the art can understand that in the case of lithography equipment suppliers usually only provide fixed light source control options (eg, light source intensity or wavelength for level 1, level 2, . . . ) In this way, the optical parameters of the actual process can be grasped by the way that the inspection platform 1a enters the interior of the lithography equipment.

However, it should be noted here that when the light source L adopts extreme ultraviolet light (EUV) with a wavelength of 13.5nm, based on the particularity of its mechanism, different measurement methods are required from light sources with other wavelengths. Specifically, when a wavelength of 365nm, 248nm, 193nm, 157nm, etc. is used as an exposure light source, it usually has a larger irradiation area (for example, much larger than the detection element 10 shown in the figure), so the detection element used to detect light parameters can be It is easier to receive relatively uniform light, so it is understandable that in these applications, the light radiation dose can be easily obtained by calculating parameters such as irradiance and time, but for extreme ultraviolet lithography (Extreme ultraviolet lithography, For EUVL), in some practical cases, the irradiation area of the target area irradiated by EUV will present a narrow and long geometric shape. For example, as shown in FIG. The surface of the substrate Wc will form a long and narrow illuminated area L', and the size of the illuminated area L' actually falling on the surface of the detection element 10 (light receiving surface 11 as described later) is much smaller than the size of the surface. It should be added that the long and narrow irradiated area where EUV lands on the target area during the actual lithography process may also be slightly curved. Therefore, since the irradiation area of EUV is significantly different from that of light sources with other wavelengths, based on this particularity, it is necessary to generate a relative displacement between the detection element 10 and the light source L (or the irradiation area L'), so as to facilitate the measurement of the detection element 10. Optical parameters (such as light intensity, radiation dose) of the light source L (or irradiation area L') are measured.

In order to facilitate the description of how the detection element 10 measures optical parameters during the lithography process with EUV, please continue to refer to FIGS. The direction (shown by arrow A) moves relative to the irradiation area L'. The size of the irradiation area L' in this direction (such as width W2) is much smaller than the size of the detection element 10 in this direction (such as length D). Here, the moving speed of the detection element 10 in the direction is defined as v, or in other words, the relative speed between the detection element 10 and the light source L (or the irradiation area L') is v. As shown in the figure, the moving path or moving direction of the detection element 10 is substantially perpendicular to the long side direction of the irradiation area L', or in other words, the direction of the relative displacement or relative speed between the detection element 10 and the irradiation area L' is substantially is perpendicular to the extension direction of the irradiation area L′. Therefore, the light-receiving surface 11 (or "active area") of the detection element 10 can pass through or pass through the irradiation area L' at a speed v, or in other words, the irradiation area L' will receive light from the detection element 10 at a speed v From one side of the surface 11 to the other side of the light-receiving surface 11, the detection element 10 can detect the incident light and generate a power signal reflecting it.

The sampling frequency of the detection element 10 is at least sufficient enough to capture a sufficient number of samples suitable for calculating the light intensity or radiation dose of the light source L within the time distance when the irradiation area L′ passes through the light receiving surface 11 . Specifically, the sampling frequency of the detection element 10 is defined as f _s1 , the scanning frequency of the light source L is f _s2 and can be expressed as v/D, where D is the length of the detection element 10 in the direction (for example, it can be about 10mm ), and the sampling frequency f _s1 or its lowest and the scanning frequency f _s2 at least meet the following conditions:

f _s1 ≥f _s2 ×N, that is, f _s1 ≥(v/D)×N, where N is the number of samples.

In one example, the number of sampling points N may be at least 10 or more (ie, N≧10).

Under this mechanism and relative movement, the detection element 10 can determine the light source according to the optical power (or radiation power) of the incident light in the irradiation area L' and the relative speed (ie, speed v) between the irradiation area L' and the irradiation area L' L is the light intensity or radiation dose. Specifically, the following calculations are involved:

Firstly, a first average illuminance E _avg of the irradiation area L' passing through the light receiving surface 11 at a first time period (time period) can be determined. For this reason, t1 and t2 can be defined as detecting the irradiation area L of the detection element 10 Two time points of the time-varying graph (time-varying graph) of the light power (or radiant power), for example, t1 can be the irradiation area L' just entering the light-receiving surface 11 from one side of the light-receiving surface 11 and completely When overlapping or covering the light-receiving surface 11 (the state shown in Figure 3), t2 can be another time when the irradiation area L' completely sweeps across the light-receiving surface 11 and just moves to the other side of the light-receiving surface 11 point (the state shown in FIG. 4), therefore, the first time distance can be expressed as (t2-t1) (ie, D/v). As for the first average illuminance E _avg can be expressed as:

，其中，P _et為檢測元件10在第一時距偵測到的光功率(或輻射功率)，(t2-t1)=D/v，D為檢測元件10在所述方向上的長度，v為檢測元件10與光源L(或照射區L’)之間的相對速度，而W1為檢測元件10在實質上垂直於所述方向之另一方向上的長度。

, wherein, _Pet is the optical power (or radiation power) detected by the detection element 10 at the first time distance, (t2-t1)=D/v, D is the length of the detection element 10 in the direction, v is the relative velocity between the detection element 10 and the light source L (or the irradiation area L'), and W1 is the length of the detection element 10 in another direction substantially perpendicular to said direction.

Then, the first average illuminance E _avg is multiplied by the first time distance (t2-t1) (that is, E _avg × (t2-t1)), and the incident light of the light source L can be determined at the first time distance (t2-t1) ) radiation dose.

Understandably, the aforementioned relative movement can be repeated or reversed one or more times to confirm the stability of the radiation dose of the light source L. For example, although not shown, for example, the detection element 10 can be made to perform the aforementioned relative movement again at a speed v, or the detection element 10 can be moved at a speed v opposite to the direction along the aforementioned arrow A, so as to move between the other two One of the time points t3 and t4 passes through the irradiation area L' within a second time distance. Understandably, under this relative movement, the relative speed between the detection element 10 and the light source L (or the irradiation area L') is still v, so A second average illuminance E' _avg can be calculated in a similar manner as follows:

，其中t3為照射區L’剛從受光面11之一側進入受光面11且完整地重疊於或覆蓋於受光面11時的時點，t4為照射區L’完整地掃過受光面11且剛移動至受光面11之另一側時的另一時點，(t4-t3)為所述第二時距(即，D/v)，P _et為檢測元件10在第二時距偵測到的光功率(或輻射功率)，D為檢測元件10在相對速度的方向上的長度，W1為檢測元件10在實質上垂直於相對速度的方向之另一方向上的長度，v為檢測元件10與光源L(或照射區L’)之間的相對速度。

, where t3 is the time point when the irradiation area L' just enters the light receiving surface 11 from one side of the light receiving surface 11 and completely overlaps or covers the light receiving surface 11, and t4 is the time point when the irradiation area L' completely sweeps across the light receiving surface 11 and just Another time point when moving to the other side of the light-receiving surface 11, (t4-t3) is the second time distance (that is, D/v), _and Pet is the detected value detected by the detection element 10 at the second time distance Optical power (or radiation power), D is the length of the detection element 10 in the direction of relative velocity, W1 is the length of the detection element 10 in another direction substantially perpendicular to the direction of relative velocity, v is the length of the detection element 10 and the light source The relative velocity between L (or the irradiated area L').

Then, the second average illuminance _E'avg is multiplied by the second time distance (t4-t3) (that is, _E'avg × (t4-t3)), and the incident light of the light source L can be determined at the second time distance (t4 - radiation dose of t3);

Then, the stability of the radiation dose of the light source L can be determined according to the aforementioned radiation dose calculated at the first time interval (t2-t1) and the radiation dose calculated at the second time interval (t4-t3). In this regard, the following steps may be involved, for example:

subtracting the radiation dose calculated at the second time interval (t4-t3) from the aforementioned radiation dose calculated at the first time interval (t2-t1) to obtain a dose difference for radiation doses at different time intervals;

Then, when the absolute value of the dose difference is greater than or equal to a critical value, it may indicate that the radiation dose of the light source L is unstable. On the contrary, when the absolute value of the dose difference is smaller than the critical value, it may indicate that the radiation dose of the light source L is stable.

Certainly, the detection method and applicable detection platform described above are only exemplary embodiments of the present invention, and the present invention is not limited thereto. In the following, other embodiments of the detection device of the present invention and related detection methods will be listed. However, it should be explained first that, for the purpose of making the drawings simple and easy to see, the components shown in the drawings matched with the following content It will be presented in a simple and schematic way. For example, the detection platform can only be represented by its detection elements, and the shape of the components and the proportion and size relationship between the components are only for schematic understanding, not for limit the invention.

For example, in order to facilitate the replacement of detection elements, please refer to FIG. 6 , an embodiment of the present invention provides a detection platform 1b, which may include a clip structure 20, and the clip structure 20 may be arranged on the substrate Wc ( For example, through any suitable position on the aforementioned carrier plate P), it is used to releasably hold the detection element 10, whereby the detection element 10 can be detachably assembled in a desired position through the clip structure 20, and it is convenient to Replacement is required.

Please refer to FIG. 7 , an embodiment of the present invention provides a detection platform 1c, which may include a plurality of detection elements 10, and these detection elements 10 may be arranged in an array. For example, the arrangement direction of the detection elements 10 may be substantially perpendicular to its moving direction or its relative movement direction with the light source L (as shown by arrow A), or in other words, the arrangement direction of the array of detection elements 10 may be substantially parallel In the long side direction or the extension direction of the irradiation area L'. Thereby, the detection elements 10 can be irradiated in different regions of the irradiation area L' at the same time, thereby helping to judge the uniformity of the light intensity of the light source L or the radiation dose.

It is further explained that the following steps may be involved in measuring the uniformity of the radiation dose of the light source L by using an array composed of a plurality of detection elements 10:

A relative displacement or relative velocity is generated between the detection elements 10 and the irradiation area L' in a specific direction (as shown by arrow A). For example, the detection elements 10 can be moved at a given speed (such as the aforementioned speed v) in the direction, so that the detection elements 10 and the irradiation area L' can produce a given speed in the direction relative displacement and relative velocity.

Then, the detection element 10 detects the incident light during the relative displacement process and obtains a plurality of optical powers correspondingly;

Then, each detection element 10 can determine the radiation dose of the light source L on it according to the obtained light power and the relative speed between it and the irradiated area L' according to the detection method described above;

Then, the uniformity of the radiation dose of the light source L can be determined according to the plurality of radiation doses calculated by the detection elements 10 . This step may specifically involve the following calculations:

For example, an average radiation dose of the radiation doses of these detection elements 10 can be calculated, and then each of these radiation doses can be subtracted from the average radiation dose to determine a plurality of dose differences about these radiation doses, When the absolute value of any one of these dose differences is greater than or equal to a critical value, it means that the radiation dose of the irradiation area L' is uneven; otherwise, when the absolute values of these dose differences are less than the critical value, it means that The radiation dose in the irradiation area L' is uniform.

Optionally, determining the uniformity of the radiation dose of the light source L can also be obtained by the following steps:

For example, the minimum of these radiation doses can be subtracted from each of the radiation doses of the detection element 10 to determine a plurality of dose differences, when the absolute value of any one of these dose differences is greater than or equal to a critical value , it can also be considered that the radiation dose of the light source L is not uniform; on the contrary, when the absolute values of these dose differences are less than the critical value, it can be said that the radiation dose of the light source L is uniform.

In addition, it is supplemented that the clip structure 20 of FIG. 6 can also be applied to the array detection element 10 of FIG. 7 or the detection element 10 of any other embodiment, so that one or more detection elements 10 can pass The clamping structure 20 is detachably assembled at a desired position.

Alternatively, in some embodiments, a material layer can also be provided on the light-receiving surface of the detection element, and the material layer only allows the waveband with a specific transmittance in the light source to pass through, or in other words, the material layer can be used to determine the wavelength of light entering the detection element. The wavelength band or wavelength range of the incident light, so that the detection element can obtain the optical power distribution of the wavelength band corresponding to the specific transmittance in the light source through the incident light passing through the material layer, and then can use this optical power distribution To judge the relevant optical parameters of the light source.

For example, referring to FIGS. 8-9, the detection platform 1d proposed in this embodiment may include a plurality of detection elements 10, and the light-receiving surface 11 of one or more of these detection elements 10 may be pre-coated or The same or different suitable materials (for example, aluminum) are coated, so that the detection elements 10 can detect multiple light wavelengths of different wavelength bands.

As shown in the figure, a material layer 31 and a material layer 32 can be respectively coated on the detection element 10 . The material layer 31 and the material layer 32 can be made of different materials and have substantially the same thickness. Due to the material characteristics of the material layer 31 and the material layer 32, only the wavebands with corresponding transmittance (transmittance) in the incident light can be passed through, or in other words, the material characteristics of the material layer 31 and the material layer 32 can determine the energy of the incident light. The band or wavelength range through which it passes. In this way, during the relative movement between the detection element 10 and the irradiation area L' in a specific direction, the detection element 10 can filter out the incident light of a specific wavelength band through the material layer 31 and the material layer 32, so as to measure the difference of the incident light Band requirements.

In one example, as shown in Figures 10-11, Figure 10 shows, for example, that the light-receiving surface 11 of the detection element 10 is coated with an aluminum material layer 31 with a density of about 2.6989g/cm³ and a thickness of about 7.0000E-02 microns (µm) , the graph of the transmittance of the received incident light and the light power (or in other words, the transmittance spectrum of the incident light), and Fig. 11 shows, for example, that the light-receiving surface 11 of the detection element 10 is coated with a density of about When the material layer 32 made of gold is 19.32 g/cm³ and the thickness is also about 7.0000E-02 μm, the curve diagram of the transmittance and optical power of the incident light received, it can be seen that the material layer 31 can make the detection element 10 detect The power distribution of the wavelength band with corresponding transmittance in the incident light is measured, or in other words, the material layer 31 can determine the wavelength range of the incident light entering the detection element 10, so that the detection element 10 can obtain the optical power distribution corresponding to this wavelength range; And the material layer 32 can make the detection element 10 detect the power distribution of another wavelength band with corresponding transmittance in the incident light, or in other words, the material layer 31 can determine another section of wavelength range of the incident light entering the detection element 10, so as to Make the detection element 10 obtain another optical power distribution corresponding to this wavelength range. In this way, it can be used to check whether the optical power distribution of the light source L is abnormal or meets requirements. For example, when the obtained optical power distributions are different from a preset optical power distribution corresponding to the predetermined wavelength of the light source L, it may indicate that the energy distribution of the light source L is not uniform.

Or, please refer to FIG. 12 , the multiple detection elements 10 of the detection platform 1e proposed in this embodiment can also be pre-plated or coated with the same or different suitable materials (for example, aluminum or gold), such as the material layer shown in the figure 33. The material layer 33 can cover the light-receiving surface 11 of the detection element 10 with a uniform thickness. The material layer 33 can be made of, but not limited to, any suitable material that is the same as or different from the material layer 31 or 32 mentioned above. Under this configuration, the material layer 33 can uniformly determine the wavelength range of the incident light that can enter the detection element 10 during the relative movement between the detection element 10 and the irradiation area L' in a specific direction, or in other words, can uniformly allow only the incident light A wavelength band of light having a specific transmittance enters the detection element 10 .

Further, optionally, the effect of spectroscopic detection can also be achieved by adjusting the signal cut-off strength of these detection elements 10 . Specifically, please also refer to FIG. 13, which shows, for example, the detection platform 1e. When the light-receiving surface 11 of the detection element 10 is coated with an aluminum material layer 33 with a density of about 2.6989g/cm³ and a thickness of about 1 µm, the detection element 10. The graph of the transmittance and optical power of the received incident light (or in other words, the transmittance spectrum of the incident light). Here, the user can adjust the signal cut-off strength of at least one of the detection elements 10, or in other words, different detection elements 10 can have different response intensities to the incident light, so as to capture the incident light with a specific transmittance. The bands (as shown in the figure correspond to the extraction segments Lv1, Lv2, and Lv3 with different penetration rates respectively). In this way, during the relative movement between the detection element 10 and the irradiation area L' in a specific direction, the adjusted detection element 10 can be used to detect whether there are unexpected or unmet requirements in the incident light of a specific wavelength band. .

Taking the extraction section Lv1 as an example, assuming that the incident light within the transmittance range corresponding to the extraction section Lv1 only needs to have an optical power distribution corresponding to 60eV, from Figure 13, it can be seen that the detection element 10 is used in the extraction The optical power distribution obtained in section Lv1 only has a waveform at about 60ev, and it can be judged that the optical power distribution of the incident light within this transmittance range meets the required optical power distribution, and it can be used to verify the optical power distribution of the incident light. The specific wavelength band meets the requirements of the lithography process; on the contrary, although it is not shown, if there are other line segments at other optical powers in this extraction section Lv1, or in other words, there is an unexpected optical power distribution, it can be known that the incident light is at The energy distribution in the specified band is not uniform.

Next, please refer to FIG. 14 , on a plurality of detection elements 10 of the detection platform 1f proposed by another embodiment of the present invention, suitable materials (for example, aluminum or gold) with the same material but different thicknesses may also be plated or coated in advance, as shown in FIG. Material layers 31 , 31 ′ and 31 ″ with different thicknesses are shown. In this way, during the relative movement between the detection element 10 and the irradiation area L' in a specific direction, the light-receiving surface 11 of these detection elements 10 can be further utilized under the condition that additional materials have been used to filter out the incident light of a specific wavelength band. The difference in thickness of the material layers 31 , 31 ′, and 31 ″ is used to distinguish the wavelength range entering the corresponding detection element 10 , so as to achieve the purpose of using the detection element 10 to confirm the optical power distribution of each wavelength range of the incident light.

In one example, as shown in Figures 15-17, Figure 15, for example, shows that the light-receiving surface 11 of the detection element 10 is coated with an aluminum material with a density of about 2.6989g/cm³ but a thickness of about 0.6µm, 0.7µm and 1µm respectively 31, 31' and 31'', the graph of the transmittance and optical power of the incident light received, under this configuration, the detection element 10 can pass through the material layers 31, 31' and 31'' According to the difference in thickness, the optical power distribution of the incident light corresponding to the bands of different transmittances can be extracted, so that it can be used to check whether the optical power distribution of the light source is abnormal or meets the requirements. For example, when the obtained optical power distribution is different from a preset optical power distribution corresponding to the predetermined wavelength of the light source L, it may indicate that the energy distribution of the light source L is not uniform.

Alternatively, the user can further adjust the signal cut-off strength of the detection element 10 under this configuration, or in other words, different detection elements 10 can be distinguished by using the thickness difference of the material layers 31, 31' and 31'' At the same time as the wavelength range, a specific extraction section (the dotted box shown in Figures 15-17) is further used to extract the wavelength band with a specific transmittance in the optical power distribution. Similarly, it is also possible to achieve the effect of detecting whether there is an unexpected or unsatisfactory situation in the incident light of a specific wavelength band.

Or, referring to FIG. 18 , the detection element 10 of the detection platform 1g proposed in this embodiment can be pre-plated or coated with a suitable material (for example, aluminum or gold) with varying thicknesses, such as the material layers with different thicknesses as shown in the figure. 31'''. Specifically, the material layer 31''' has a thickness variation at least in the direction of the relative displacement or relative velocity between the detection element 10 and the light source L (as shown by arrow A).

Under this configuration, when the relative displacement between the detection element 10 and the irradiation area L' occurs in a specific direction, similar to the effect shown in FIG. Different wavelengths of light can also achieve the purpose of using the detection element 10 to confirm the spectrum of the incident light.

Of course, those skilled in the art can understand based on the foregoing introduction that the concepts of the foregoing embodiments can be integrated according to other actual requirements. For example, on the basis of the aforementioned configuration in FIG. 14 , the signal cut-off strength (or response strength) of the detection element 10 can be further adjusted, so as to use a specific detection element 10 to detect whether there is an abnormality in the incident light of a specific wavelength band. Situations where demand is expected or not met.

In addition, for purposes such as ease of use and transportation, as shown in FIG. 19 , the detection platform of any one of the foregoing embodiments of the present invention (taking the detection platform 1a as an example here) can be stored in a storage box 41 to perform detection on the detection element. Operations such as charging and/or information transmission, so that relevant data can be transmitted to the control center (not shown) in a wireless/wired manner through the storage box 41 .

Alternatively, as shown in FIG. 20 , a storage box 42 is proposed, which can be used to store a plurality of detection platforms of any one of the foregoing embodiments (here, the detection platform 1a is taken as an example). The storage box 42 may be, but not limited to, a Front Opening Unified Pod (FOUP) integrated with wireless charging and/or data transmission functions. In this way, operations such as charging and/or information transmission can be performed on multiple detection platforms at one time or in batches, and relevant data can be transmitted to the control center (not shown) in a wireless/wired manner through the storage box 42 ).

Finally, it is supplemented that, in the aforementioned mode of integrating the detection platform into the wafer, those skilled in the art can easily understand that the detection element can also be changed or replaced with a , Record and analyze other physical quantities (such as temperature, particle state, resistance, vibration, humidity, spectrum, alignment) sensors.

According to the detection method and detection platform disclosed in the foregoing embodiments of the present invention, since the detection element of the detection platform uses the substrate as a carrier, it can enter the lithography equipment along with the substrate to measure, record or analyze the lithography in real time and accurately. The energy parameters (such as light intensity, wavelength, radiation dose, etc.) related to the radiation source during the process can help to improve the autonomy of the process control. Accordingly, it is beneficial for the user side to improve the stability of the in-process, thereby helping to improve the yield rate.

In some implementations, the detection elements can be extended to array measurement, which can arrange the detection elements in an array, so as to achieve the purpose of recording and analyzing the uniformity of radiation dose in real time.

In some implementations, the detection element can be plated or coated with material layers of different materials, or the detection element can be coated with material layers of the same material but with different thicknesses to capture or absorb different wavelengths of light sources. In addition, with the adjustment of the signal cut-off strength or magnification of the detection element, the analysis can be carried out for the specific wavelength of the light source.

Although the present invention is disclosed by the aforementioned embodiments, they are not intended to limit the present invention. Changes and modifications made without departing from the spirit and scope of the present invention all belong to the scope of patent protection of the present invention. For the scope of protection defined by the present invention, please refer to the appended scope of patent application.

1a-1f: detection platform 10: detection element 11: light receiving surface 20: clip structure 31, 31', 31'', 31''', 32, 33: material layer 41: storage box 42: storage box A: arrow B: Power supply unit C: Charging unit DC: Controller D, W1: Length E _avg : First average illuminance _E'avg : Second average illuminance f _s1 : Sampling frequency f _s2 : Scanning frequency L: Light source L': Irradiation Area Lv1, Lv2, Lv3: Extraction section N: Number of sampling points P: Carrier board P _et : Power t1, t2, t3, t4: Time point T: Mobile platform v: Velocity Wc: Substrate W2: Width

The following description should be read in conjunction with the corresponding drawings to help understand various implementation aspects of the present invention. It should be noted that the various features in the illustrations may not be drawn to scale. In fact, the size and proportion of the various features in the illustrations can be adjusted and scaled arbitrarily for the purpose of easy understanding and explanation. FIG. 1 is a schematic diagram of a detection platform according to an embodiment of the present invention being carried on a substrate on a mobile platform of a lithography equipment. FIG. 2 is a flow chart of the operation of the detection platform in FIG. 1 . 3 to 4 are simple schematic diagrams showing the detection platform of an embodiment of the present invention when measuring the radiation dose of the light source. Fig. 5 is a time-varying graph of the radiation power of the measurement platform when the light source is measured. FIG. 6 is a schematic exploded view showing a detection platform carried on a substrate according to another embodiment of the present invention. FIG. 7 is a simple schematic diagram illustrating another embodiment of the present invention in which a detection platform is carried on a substrate. FIG. 8 is a schematic diagram illustrating another embodiment of the present invention in which a detection platform is carried on a substrate. FIG. 9 is a partially enlarged schematic diagram of FIG. 8 . 10-11 are graphs of the transmittance and optical power of incident light captured by different detection elements under the configuration of the detection platform in FIG. 8 . FIG. 12 is a partially enlarged schematic view showing a detection platform carried on a substrate according to another embodiment of the present invention. FIG. 13 is a graph of the transmittance and optical power of incident light under the configuration of the detection platform in FIG. 12 . FIG. 14 is a partially enlarged schematic view showing a detection platform carried on a substrate according to another embodiment of the present invention. 15-17 are graphs of the transmittance and optical power of incident light captured by different detection elements under the configuration of the detection platform in FIG. 14 . FIG. 18 is a partially enlarged schematic view showing a detection platform carried on a substrate according to another embodiment of the present invention. FIG. 19 is a simple schematic diagram showing another embodiment of the present invention where the detection platform and the substrate are stored together in a storage box. FIG. 20 is a simple schematic diagram showing another embodiment of the present invention where the detection platform and the substrate are stored together in a storage box.

1a: Detection platform

10: Detection element

11: Light-receiving surface

A: arrow

B: Power supply unit

C: charging unit

DC: controller

L: light source

L': irradiation area

P: carrying plate

T: mobile platform

Wc: Substrate

Claims (27)

A detection method suitable for detecting a light source for a substrate, the light source being suitable for forming an irradiation area on a surface of the substrate, the detection method comprising: placing at least one detection element on the surface of the substrate; causing the at least one detection element to generate a relative displacement and a relative speed with the irradiation area in one direction, so that the at least one detection element passes through the irradiation area, wherein the irradiation area The size in the direction is much smaller than the size of the at least one detection element in the direction; make the at least one detection element detect the optical power of the incident light of the irradiation area in the process of the relative displacement; and according to the detected The received optical power and the relative speed determine the optical parameters of the light source. The detection method as described in Claim 1, wherein the step of determining the optical parameters of the light source comprises: determining a first average illuminance of the irradiation area at a first time distance, wherein the first time distance is (t2-t1 ), the first average illuminance is E _avg , and expressed as:

, wherein _Pet is the optical power detected by the at least one detection element at the first time distance, and t1 and t2 are two time s points of the time-varying diagram of the optical power of the at least one detection element in the detection irradiation area , (t2-t1)=D/v, D is the length of the at least one detection element in the direction of the relative velocity, v is the relative velocity between the at least one detection element and the irradiation area, W1 is the the length of at least one detection element in another direction substantially perpendicular to the direction of the relative velocity; and multiplying the first average illuminance by the first time distance to determine the radiation dose of the light source at the first time distance . The detection method as described in claim 2, wherein the step of determining the radiation dose of the light source further includes: determining a second average illuminance of the irradiation area at a second time interval, wherein the second time interval is (t4- t3), the second average illuminance is E' _avg , and expressed as:

, wherein _Pet is the optical power detected by the at least one detection element at the second time distance, t3 and t4 are the other two time points of the time-varying diagram of the optical power of the at least one detection element in the detection irradiation area, (t4-t3)=D/v; multiply the second average illuminance by the second time distance to determine the radiation dose of the light source at the second time distance; and according to the irradiation area at the first time distance and the The radiation dose of the second time interval determines the stability of the radiation dose of the light source. The detection method as described in Claim 3, wherein the step of determining the stability of the radiation dose of the light source further includes: calculating a dose difference between the radiation doses of the first time interval and the second time interval; and When the absolute value of the dose difference is greater than or equal to a critical value, it means that the radiation dose of the light source is unstable. The detection method as described in claim 1, wherein the sampling frequency of the at least one detection element is f _s1 , the scanning frequency of the light source is f _s2 and can be expressed as v/D, and it satisfies the following conditions: f _s1 ≥ f _s2 ×N, where N is the number of samples. The detection method according to claim 5, wherein N≥10. The detection method as described in claim 1, wherein the step of placing the at least one detection element on the surface of the substrate comprises: The at least one detection element is releasably held on the surface of the substrate by using at least one clip structure. The detection method as described in claim 1, wherein the at least one detection element includes a plurality of detection elements, and the detection method further includes: causing the detection elements and the irradiation area to generate the relative displacement and the relative velocity in the direction, so that the detection elements pass through the irradiation area; Make the detection elements detect the incident light of the irradiation area in the process of the relative displacement to obtain the corresponding optical power; Determine the radiation dose of the light source to each of the detection elements according to the corresponding optical power and the relative speed obtained by the detection elements; and According to the radiation dose of the detection elements, the uniformity of the radiation dose of the light source is determined. The detection method as described in Claim 8, wherein the step of determining the uniformity of the radiation dose of the light source further includes: calculating an average radiation dose of the radiation doses of the detection elements; calculating the difference between the radiation dose of each of the detection elements and the average radiation dose to obtain a plurality of dose differences; and When the absolute value of any one of the dose differences is greater than or equal to a critical value, it means that the radiation dose of the light source is not uniform. The detection method as described in Claim 8, wherein the step of determining the uniformity of the radiation dose of the irradiation area according to the radiation dose of the detection elements further includes: calculating the difference between the radiation dose of each of the detection elements and the smallest of the radiation doses of the detection elements to obtain a plurality of dose differences; and When the absolute value of any one of the dose differences is greater than or equal to a critical value, it means that the radiation dose of the irradiation area is not uniform. The detection method according to claim 8 further includes: making an arrangement direction of the detection elements substantially parallel to the direction or the long side direction of the irradiation area. The detection method as described in claim 1 further includes: A material layer is provided on a light-receiving surface of the at least one detection element, wherein the material layer is used to determine the wavelength range of incident light entering the at least one detection element; The at least one detection element detects incident light passing through the material layer to obtain an optical power distribution; and When the obtained optical power distribution is different from a preset optical power distribution corresponding to a predetermined wavelength of the light source, it means that the energy distribution of the incident light of the light source is uneven. The detection method according to claim 12, wherein the thickness of the material layer varies in the direction. The detection method as described in claim 1, wherein the at least one detection element includes a plurality of detection elements, and the detection method further includes: A material layer is provided on one light-receiving surface of each of the detection elements, wherein the material layers have the same thickness and different materials, and the material layers are respectively used to determine the wavelength range of the incident light entering the detection elements; The detecting elements detect incident light passing through the material layers to obtain corresponding optical power distribution; and When the obtained optical power distribution is different from a preset optical power distribution corresponding to a predetermined wavelength of the light source, it means that the energy distribution of the incident light of the light source is uneven. The detection method as described in claim 1, wherein the at least one detection element includes a plurality of detection elements, and the detection method further includes: A material layer is provided on one light-receiving surface of each of the detection elements, wherein the material layers have different thicknesses and the same material, and the material layers are respectively used to determine the wavelength range of the incident light entering the detection elements; The detecting elements detect incident light passing through the material layers to obtain corresponding optical power distribution; and When the obtained optical power distribution is different from a preset optical power distribution corresponding to a predetermined wavelength of the light source, it means that the energy distribution of the incident light of the light source is uneven. The detection method as described in claim 1 further includes: adjusting the response intensity of the at least one detection element to the incident light of the light source, so as to obtain the optical power distribution of the wavelength band with a specific transmittance in the incident light of the light source; and When the obtained optical power distribution is different from a preset optical power distribution corresponding to a predetermined wavelength of the light source, it means that the energy distribution of the incident light of the light source is uneven. The detection method according to any one of claims 12-15, wherein the material layer is made of gold or aluminum. The detection method according to any one of claims 12-16, wherein the predetermined wavelength of the light source is 13.5 nanometers. A detection platform adapted to detect a light source for a substrate, the light source being suitable for forming an irradiation area on a surface of the substrate, the detection platform comprising: at least one detection element, adapted to be arranged on the surface of the substrate, to produce a relative displacement and a relative velocity with the substrate in a direction and the irradiation area and detect the optical power of the incident light of the light source; and a control A device is electrically connected to the at least one detection element, so as to determine the optical parameters of the light source according to the optical power obtained by the at least one detection element and the relative speed. The detection platform according to claim 19, wherein the substrate is a silicon wafer, a glass wafer, a thinned wafer or an etched wafer. The detection platform as claimed in claim 19 further comprises at least one clamping structure for releasably holding the at least one detection element on the surface of the substrate. The detection platform as described in claim 19 further includes a charging unit and at least one power supply unit, the charging unit is used to charge the power supply unit in a wireless or wired manner, and the power supply unit is used to provide the at least one detection Component power. The detection platform as claimed in claim 19, wherein the at least one detection element comprises a plurality of detection elements arranged in an array. The detection platform according to claim 23, wherein the detection elements are arranged along the direction substantially parallel to the direction or the long side of the irradiation area. The detection platform as described in claim 23, wherein one light-receiving surface of each detection element is provided with a material layer, and the material layers on the detection elements have the same thickness and different materials. The detection platform as described in claim 23, wherein a material layer is provided on a light-receiving surface of each detection element, and the thicknesses of the material layers on the detection elements are different and the materials are the same. The detection platform according to claim 19, wherein a light-receiving surface of the at least one detection element is provided with a material layer, and the thickness of the material layer varies in the direction.

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