Characterization of photosensitive materials

Abstract

Embodiments of the present disclosure generally relate to a method for providing real-time characterization of photoresist properties. In some embodiments, a method for producing a patterned photoresist on a substrate includes forming an unpatterned photoresist on the substrate, exposing the unpatterned photoresist to a first dose of EM radiation with a first light source at a first location on the unpatterned photoresist, measuring optical properties of the unpatterned photoresist, and exposing the unpatterned photoresist to a second dose of EM radiation at the first location on the unpatterned photoresist to produce a patterned or partially patterned photoresist. The second dose of EM radiation has a larger wavelength, a larger pulse rate, or a longer exposure duration than the first dose of EM radiation from the second light source. Also, at least one of the first light source and the second light source is an on-board metrology device.

Description

[Technical field]

[0001]

[0001] Embodiments of the present disclosure relate generally to photosensitive materials, and more specifically to photoresist technology and methods for characterizing the properties of photoresists. [Background technology]

[0002]

[0002] Integrated circuits have evolved into complex devices that may contain millions of components (e.g., transistors, capacitors, and resistors) on a single chip. Photolithography may be used to form the components on the chip. Generally, the process of photolithography includes forming a photoresist layer on a substrate. The photoresist layer may be formed, for example, by spin coating. After deposition of the photoresist, the substrate is transferred to a processing chamber for exposure. In the exposure step, a photomask or reticle may be used to selectively expose certain areas of the photoresist layer disposed on the substrate to electromagnetic (EM) radiation, such as EM radiation in the ultraviolet (UV) or extreme ultraviolet (EUV) range, using a first EM source. In many cases, multiple exposure sub-processes may occur such that multiple portions of the photoresist layer disposed on the substrate are each exposed to a different dose of EM radiation. The dose of EM radiation includes its magnitude (frequency or wavelength) and its duration.

[0003]

[0003] After exposure, the substrate may be heated in a post-exposure bake and development process to remove uncrosslinked photoresist. After the post-exposure bake and development process, another EM source is used to measure the optical properties of the photoresist film at multiple locations corresponding to each of the different doses of EM radiation exposed to the photoresist film. However, current methods that utilize X-ray and optical metrology techniques to measure the optical properties of unexposed or partially exposed photoresist suffer from the limitation that the resist changes into a different chemical compound when exposed to wavelengths below 400 nm, such as the wavelengths of UV or EUV tools. Meanwhile, at larger wavelengths, such as wavelengths above 400 nm, the sensitivity of analyzing the optical or material properties of the material is low, resulting in limited insight into the optical or material properties that are important for predicting the behavior of the photoresist film.

[0004]

[0004] The measured optical or material properties can be compared to contrast curve analysis, which shows the change in thickness or other optical or material properties of the photoresist after exposure / before baking and developing as a function of the dose of EM radiation received. However, as mentioned above, currently known processes require the use of multiple EM sources in different chambers to achieve these results. Also, current processes cannot account for or separate the effect of the dose of electromagnetic radiation from initial non-uniformities in the photoresist due to inconsistencies in the deposition process.

[0005]

[0005] Figure 1 shows a prior art method 100 for producing a patterned photoresist on a substrate. In operation 110, an unpatterned photoresist, such as a metal photoresist, is deposited above the substrate, often in a spin-on deposition process. In operation 120, the substrate is transferred to a second chamber and exposed to multiple doses of EM radiation by a first EM source corresponding to different locations on the unpatterned photoresist to pattern the photoresist. The EM radiation from the first EM source may have a wavelength of about 400 nm or greater. In operation 130, the substrate is transferred to a third chamber for a post-exposure bake and develop process. In operation 140, a second EM source measures the remaining thickness at multiple locations on the patterned photoresist, each location corresponding to a distinct dose of EM radiation.

[0006]

[0006] In the prior art method 100 of Figure 1 described above, the measurement of changes in the optical or material properties of the patterned photoresist in operation 140 cannot be attributed solely to the dose of EM radiation received. This is due to the confounding factor of the initial non-uniformity of the photoresist from operation 110, since each EM radiation dose and subsequent measurement of the optical or material properties of the altered photoresist were performed at different locations. Moreover, the EM source that performs the task of measuring the optical or material properties of the photoresist often itself affects these properties of the photoresist during the measurement process.

[0007]

[0007] Therefore, there is a need for improved methods for providing characterization of photoresist properties during photolithography processes. Summary of the Invention

[0008]

[0008] Embodiments of the present disclosure relate generally to photosensitive materials, and more specifically to photoresist techniques and methods for providing real-time characterization of photoresist properties throughout post-deposition operations including exposure, bake, and development processes.

[0009]

[0009] In one or more embodiments, a method for producing a patterned photoresist on a substrate is provided, comprising forming an unpatterned photoresist on a substrate, exposing the unpatterned photoresist to a first dose of electromagnetic (EM) radiation with a first light source at a first location on the unpatterned photoresist, measuring optical properties of the unpatterned photoresist, and exposing the unpatterned photoresist to a second dose of EM radiation at the first location on the unpatterned photoresist to produce a patterned or partially patterned photoresist. The second dose of EM radiation has a larger wavelength, a larger pulse rate, or a longer exposure duration than the first dose of EM radiation from the second light source. Also, at least one of the first light source and the second light source is an on-board metrology (OBM) device.

[0010] In another embodiment, a method of producing a patterned photoresist on a substrate is provided, comprising forming an unpatterned photoresist on the substrate, exposing the unpatterned photoresist to a first dose of UV light using a first light source at a first location on the photoresist to produce a patterned or partially patterned substrate, where the first dose of UV light lasts for about 1 millisecond or less, and measuring an optical property of the photoresist at the first location. The method also includes irradiating the patterned or partially patterned photoresist at the first location on the photoresist with a second dose of UV light, where the second dose of UV light has a larger wavelength, a larger pulse rate, or a longer exposure duration than the first dose of UV light from the first light source.

[0011] In some embodiments, a method of producing a patterned photoresist on a substrate is provided, comprising forming an unpatterned photoresist on a substrate, exposing the unpatterned photoresist to a first dose of EM radiation using a first light source at a first location on the unpatterned photoresist, and measuring optical properties of the unpatterned photoresist. The method also comprises exposing the unpatterned photoresist to a second dose of EM radiation at the first location on the unpatterned photoresist to create a patterned or partially patterned photoresist, and analyzing the optical properties of the patterned or partially patterned photoresist as a function of the dose of EM radiation received. The method includes exposing the patterned photoresist or partially patterned photoresist to a third dose of EM radiation with a first light source at a first location on the patterned photoresist or partially patterned photoresist, where the third dose of EM radiation is the same as the first dose of EM radiation; measuring optical properties of the patterned photoresist or partially patterned photoresist; and exposing the patterned photoresist or partially patterned photoresist to a fourth dose of EM radiation at the first location on the patterned photoresist or partially patterned photoresist, where the fourth dose of EM radiation is different from the second dose of EM radiation.

[0012]

[0012] In order that the above-mentioned features of the present disclosure may be understood in detail, a more particular description of the present disclosure briefly summarized above may be obtained by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings show only exemplary embodiments, and therefore should not be considered as limiting the scope of the present disclosure, as other equally effective embodiments may be permitted. [Brief description of the drawings]

[0013] [Figure 1]

[0013] A prior art method for characterizing photoresist by contrast curve is shown. [Diagram 2]

[0014] 1 illustrates a method for characterizing a photoresist according to one or more embodiments described and discussed herein. [Diagram 3]

[0015] 1 illustrates a cross-sectional view of a portion of an integrated circuit during a photolithography process in accordance with one or more embodiments described and discussed herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014]

[0016] For ease of understanding, wherever possible, the same reference numerals have been used to designate identical elements common to the figures. It is believed that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

[0015]

[0017] According to embodiments described and disclosed herein, a method for measuring optical or material properties of a photoresist during a photolithography process involves the use of a first electromagnetic (EM) source, such as one utilized in an on-board metrology (OBM) device or other optical tool. Such an EM source can be a standalone EM source or an on-board EM source, such as an in-situ EM source or an ex-situ EM source (where in-situ and ex-situ, as used herein, refer to a location relative to a processing chamber). An on-board EM source advantageously avoids possible contamination issues and allows monitoring in a mass production environment. The measured optical or material properties include thickness, surface roughness, chemical composition, complex dielectric constant, complex refractive index, defects in the photoresist, stress in the photoresist, other properties of the photoresist, and / or any combination thereof. In some embodiments, the process chamber includes multiple EM sources.

[0016]

[0018] To measure the optical or material properties of the photoresist, such as film thickness, without substantially changing the optical or material properties of the photoresist, a first EM source is used to expose the unpatterned photoresist to a single short pulse of EM radiation and obtain reflected light. The duration, intensity, and spectral composition of the single short pulse can be adjusted to achieve best performance based on the material properties. The exposure to the single short pulse does not change the photoresist because the dose of electromagnetic radiation is too small to change the chemical and morphological properties of the photoresist. The EM radiation may be any suitable form of EM radiation, such as ultraviolet (UV), X-ray, extreme ultraviolet (EUV) light, or other suitable form of EM radiation. In some embodiments, an electron beam may also be suitably used instead of or in conjunction with the EM radiation. After exposing the photoresist to the single short pulse (characteristic first dose), the first EM source is used to expose the photoresist to a second dose of EM radiation (which may have a larger wavelength range, higher pulse frequency, longer exposure duration, or any combination thereof than the first dose of EM radiation). The first dose followed by the second dose can be repeated multiple times in a cycle until the intended change in the photoresist is achieved and measured, e.g., until the optical or material properties of the photoresist and the changes therein are completely or accurately characterized, e.g., the first dose followed by the second dose can be repeated at least 3 times, at least 10 times, at least 20 times, or at least 40 times.

[0017]

[0019] By utilizing the methods described herein, measurements of the optical properties of the photoresist can be collected at the same location on the photoresist, thus eliminating the influence or interference of initial deposition non-uniformity on the change in the optical properties of the photoresist (e.g., the effect of EM radiation dose and dose duration on the optical properties of the photoresist can be separated from the effect of initial non-uniformity of the photoresist on the optical properties of the photoresist). By separating the effects of dose magnitude and duration on the photoresist, instant correlations can be found between the lithographic performance of the photoresist and small changes in EM radiation dose. These correlations can be further used to define and adjust lithographic settings during device fabrication.

[0018]

[0020] The change in the optical or material properties of the photoresist allows subsequent processing steps, such as deposition parameters and / or exposure dose, to be adjusted in order to improve lithographic print quality. Exemplary improvements in lithographic print quality may include critical dimension (CD), CD uniformity, line edge roughness (LER), line width roughness (LWR), dose to size, or any combination thereof. Given the real-time measurement of the optical properties of the photoresist on the substrate, the process gas flow rate, or exposure dose, or duration above the substrate during the deposition process may be increased or decreased. Gas flow rate, deposition duration, and deposition temperature may also be adjusted based on the measured photoresist properties.

[0019]

[0021] 2 illustrates a method 200 of fabricating a patterned photoresist on a substrate according to an embodiment of the present disclosure. In operation 210, an unpatterned photoresist film layer 306 is deposited above a substrate 302 in a first processing chamber. The unpatterned photoresist 306 may be formed of any suitable photoresist material. The photoresist material may be or may include one or more chemically amplified resists (CARs), one or more light absorbing resists, one or more metal materials, one or more metal oxide (MOX) materials, one or more non-metallic materials, or any combination thereof. In some examples, the photoresist 306 includes photoresist material that may be or may include metals, metal oxides, and / or clusters of one or more elements including indium, tin, bismuth, antimony, cesium, molybdenum, hafnium, zirconium iron, cobalt, nickel, copper, zinc, silver, platinum, lead, iodine, tellurium, or any combination thereof. In some embodiments, the photoresist 306 is a dry photoresist. The photoresist may include a positive or negative tone resist resin layer, including, but not limited to, acrylates, novolac resins, poly(methyl methacrylate), and poly(olefin sulfones). The photoresist may also include a photoacid generator, which may include, but is not limited to, sulfonate compounds, onium salts, introbenzyl esters, s-triazine derivatives, ionic iodonium sulfonates, perfluoroalkanesulfonates, aryl triflates and their derivatives and analogs, pyrogallol derivatives, and alkyl disulfones. In one or more examples, upon exposure to EM radiation, the photoacid generator produces or generates one or more charged species that result in a latent image of acid in the resist resin. In some embodiments, a photomask or reticle may be configured to transfer a pattern, including lines, into the photoresist. In other embodiments, maskless lithography techniques may be used.

[0020]

[0022] The photoresist may be deposited by any suitable method, such as a spin-coating process or a vapor deposition process (e.g., a chemical vapor deposition (CVD) process). In a CVD process, two or more precursor gases are introduced into a process chamber where they may mix and react to form an integrated polymeric material. The precursor gases may be injected through separate gas inlets or through a single gas inlet. The precursor gases are injected into the process chamber such that they do not mix until above the substrate. In a spin-coating process, the spin speed can be adjusted to obtain a desired coating thickness. The spin-coating process advantageously allows for thinner deposition layers required for micropatterning. During the spin-coating process, the substrate may be spun at any speed, depending on the film viscosity and the desired thickness of the spun film. By way of example, the substrate may be spun at a speed of about 1,000 revolutions per minute (rpm) to about 5,000 rpm.

[0021]

[0023] In some embodiments, an optional underlayer 304 is deposited between the substrate 302 and the photoresist 306 such that the underlayer 304 and the photoresist 306 have an interface 305. The interface 305 may play a role in the performance of photoresist lithography printing. In some embodiments, such performance may be controlled by selecting an underlayer with a particular band structure and / or dielectric constant. The underlayer may be or include a high-k layer, a barrier layer, a conductive layer, an interface layer, other suitable layers and / or combinations thereof. The underlayer may be or include one or more materials including one or more carbon-based materials, one or more metal-based materials, one or more oxides, one or more nitrates, one or more silicon-based materials, one or more spin-on-glass (SOG) materials, one or more spin-on-carbon (SOC) materials, one or more anti-reflective coatings, one or more adhesion-based materials, or any combination thereof.

[0022]

[0024] After operation 210, the substrate 302 may be transferred to a second chamber. In operation 220, a first EM source 340 exposes the unpatterned photoresist 306 to a first dose of EM radiation at a first location 308 on the unpatterned photoresist 306 to measure optical or material properties of the photoresist 306 in the second chamber. The optical or material properties may include a photoresist thickness 310, a surface roughness, a chemical composition, a complex dielectric constant, a complex refractive index, or other optical properties of the photoresist 306, and may be determined using ellipsometry, reflectometry, or photoemission fluorescence. The first EM source 340 may be an on-board metrology (OBM) device and may be in-situ or ex-situ. The EM radiation may be any suitable form of EM radiation, such as UV light, X-rays, EUV light, or other suitable form of EM radiation. In some embodiments, an electron beam may also be suitably used instead of or in combination with the EM radiation. The first dose of EM radiation is a single short pulse of EM radiation that does not change the optical or material properties of the photoresist 306 .

[0023]

[0025] The first dose of EM radiation may have a duration of about 100 milliseconds or less, such as about 2 milliseconds or less, e.g., about 1 millisecond or less, e.g., about 2 microseconds or less, e.g., about 1 microsecond or less, such as about 100 milliseconds or less. The first dose of EM radiation may have a wavelength between about 13 nm and about 800 nm. In some embodiments, a scanning beam or imager is also used to obtain spatial resolution of the photoresist. For example, the scanning beam or imager can provide information about the surface morphology or defects of the photoresist film.

[0024]

[0026] In operation 230, a second light pulse exposes the unpatterned photoresist 306 to a second dose of EM radiation in a second chamber to create a patterned or partially patterned photoresist. In some embodiments, the second light pulse may be emitted by a first EM source 340. In some embodiments, the second light pulse may be emitted by a second EM source (not shown). The second dose of EM radiation covers at least a first location 308 on the photoresist 306. The optical or material properties of the photoresist 306 change after the second dose of EM radiation. For example, a thickness 310 of the patterned or partially patterned photoresist 306 after the second dose is thinner than a thickness 310 of the unpatterned photoresist 306 before the second dose. The second dose of EM radiation may be any suitable form of EM radiation, such as UV light, X-rays, EUV light, or other suitable form of EM radiation. In some embodiments, an electron beam may also be suitably used in place of or in combination with the EM radiation. In some embodiments, the second dose of EM radiation has one or more of a greater wavelength than the first dose of EM radiation, a greater frequency of pulses than the first dose, and a longer duration than the first dose.

[0025]

[0027] In optional operation 240, operations 220 and 230 are repeated on the patterned photoresist 306 or partially patterned photoresist 306 to collect or otherwise generate multiple data points of optical or material properties by operation 220. The collected data points include measurements of optical or material properties of the photoresist, and changes in these properties are fully characterized to create an accurate contrast curve. A full characterization of changes in the measured optical or material properties of the photoresist depends on many factors, such as the brightness of the illumination during the exposure process between measurements. For example, the brighter the illumination during the exposure process between measurements, the fewer points are required to fully characterize changes in the measured optical or material properties of the photoresist. In some embodiments, which can be combined with other embodiments, operations 220 and 230 are repeated between about 30 and about 500 times, such as between about 100 and about 300 times, such as between about 150 and about 250 times. In some embodiments, operations 220 and 230 may be repeated up to 10 times in about 1 second or less. It is contemplated that optical or material properties of photoresist may also be measured during deposition of the photoresist using the methods described herein.

[0026]

[0028] In optional operation 250, the patterned photoresist 306 or the partially patterned photoresist 306 is treated with a bake and / or develop sub-operation, in which the patterned photoresist 306 may be heated to remove uncrosslinked photoresist. Prior to the post-exposure bake and / or develop sub-operations, the patterned substrate 302 may be transferred to a third processing chamber. During the post-exposure bake sub-operation, the substrate is heated and the photoacid generator in the patterned photoresist 306 or the partially patterned photoresist continues to change the chemical properties of the exposed portions of the patterned photoresist 306. In one or more embodiments, the patterned photoresist 306 or partially patterned photoresist 306 on the substrate is heated to a temperature in the range of about 30° C., about 35° C., about 40° C., about 50° C., about 65° C., about 80° C., or about 100° C. to about 120° C., about 150° C., about 180° C., about 200° C., about 250° C., about 300° C., about 400° C., or higher during a post-exposure bake and / or development process. For example, the patterned photoresist 306 or partially patterned photoresist 306 may be heated during a post-exposure bake and / or develop process to a temperature in the range of about 30° C. to about 400° C., about 50° C. to about 400° C., about 50° C. to about 200° C., about 50° C. to about 100° C., about 50° C. to about 80° C., about 100° C. to about 400° C., about 100° C. to about 300° C., about 100° C. to about 250° C., about 100° C. to about 200° C., or about 100° C. to about 150° C. Optionally, during the post-exposure bake sub-operation, the pressure in the processing chamber may also be reduced by a vacuum source.

[0027]

[0029] In some embodiments of optional operation 250, which may be combined with other embodiments, operations 220 and 230 are repeated between about 30 and about 500 times, such as between about 100 and about 300 times, such as between about 150 and about 250 times. In some embodiments, operations 220 and 230 may be repeated up to 10 times in about 1 second or less. It is contemplated that optical or material properties of the photoresist may also be measured during deposition of the photoresist using the methods described herein.

[0028]

[0030] After an optional post-exposure bake sub-operation, the substrate, and in particular the photoresist, may be developed and rinsed. Depending on the type of photoresist used, the areas of the substrate exposed to EM radiation may either be resistant to removal or more susceptible to removal. The patterned or partially patterned photoresist 306 may be developed by exposure to a developer, for example, sodium hydroxide solution, tetramethylammonium hydroxide aqueous solution, xylene, or Stoddard solvent. The substrate may be rinsed, for example, with water or n-butyl acetate. Optionally, the substrate may be hard baked and inspected. An optional pre-exposure bake sub-operation is also contemplated to evaporate or partially evaporate the photoresist solvent.

[0029]

[0031] In optional operation 260, data points of optical or material properties of the patterned or partially patterned photoresist 306 collected by repeating operations 220 and 230 are analyzed to create a dynamic model of the photoresist. For example, a contrast curve analysis of the photoresist 306 may be created to show the change in material or optical properties of the photoresist 306 as a function of the dose of EM radiation. In other embodiments, the material or optical properties of the photoresist 306 may be considered as a function of exposure durations where the dose of EM radiation emitted from a source, such as the first EM source 340, is held constant for different lengths of time during the exposure.

[0030]

[0032] Examples of data that may be collected by the above method include thickness of the photoresist 306 versus dose of EM radiation, and / or thickness of the patterned or partially patterned photoresist 306 versus duration of exposure at a constant dose of EM radiation, where thickness may be replaced by any number of optical or material properties of interest of the photoresist. In this manner, the time-dependent results of the optical properties may be analyzed using trends (e.g., slopes, rates of change, or other critical values) to extrapolate a quantity of interest (e.g., optical or material properties) at any point in time, such as time equal to zero (e.g., before the exposure process) or time equal to infinity (e.g., after the photoresist film is fully developed).

[0031]

[0033] Data collected using the above methods can be utilized to modify subsequent deposition and exposure processes to enhance process uniformity. For example, wafer-to-wafer uniformity can be improved by adjusting the deposition or exposure of subsequent wafers. For example, uniformity within a single wafer can be improved in real time by adjusting the deposition or exposure characteristics of the wafer based on the collected optical property data points. Wafer deposition characteristics can include gas flow rate, deposition duration, and / or deposition temperature. Wafer exposure characteristics can include exposure duration and / or exposure temperature. In some examples, deposition or exposure characteristics can be controlled via tuning knobs. Photoresist chemical composition gradients can be controlled in real time by adjusting photoresist deposition or exposure characteristics based on the collected optical property data points.

[0032]

[0034] By utilizing the above methods, measurements of the optical or material properties of the photoresist can be collected at the same location on the photoresist, thus eliminating the influence or interference of initial deposition non-uniformities on the changes in the optical or material properties of the photoresist (e.g., the effect of EM radiation dose and dose over time on the optical or material properties of the photoresist can be separated from the effect of initial non-uniformities of the photoresist on the optical or material properties of the photoresist). Furthermore, exposure and measurements can be performed in the same chamber, resulting in less downtime during substrate transfer and improved overall throughput. The methods described herein allow optical measurements that do not affect the optical or material properties of the photoresist, thereby allowing further insight into the effect of EM radiation dose on the optical or material properties of the photoresist. This allows for immediate correlation of slight dose changes of EM radiation with the properties of the photoresist.

[0033]

[0035] Additionally, the methods described and discussed herein can be utilized to determine the chemical state of the photoresist 206. In one or more examples, the methods described and discussed herein include observing the localized energy field of the photoresist 206 and absorbing light reflected by the band gap to approximate the chemical state. Additionally, the methods described and discussed herein allow for measuring the sensitivity of the photoresist to different doses or lengths of exposure processes without the need for an EUV chamber. Thus, measurements can be performed on both patterned and unpatterned wafers, inside and outside the deposition chamber, allowing for rapid pre-screening of new photoresists.

[0034]

[0036] Embodiments of the present disclosure further relate to any one or more of Examples 1 to 15 below.

[0037] 1. A method of producing a patterned photoresist on a substrate comprising: forming an unpatterned photoresist on a substrate; exposing the unpatterned photoresist to a first dose of electromagnetic (EM) radiation using a first light source at a first location on the unpatterned photoresist; measuring optical properties of the unpatterned photoresist; and exposing the unpatterned photoresist to a second dose of EM radiation at the first location on the unpatterned photoresist to produce a patterned or partially patterned photoresist, wherein the second dose of EM radiation has a larger wavelength, a larger pulse rate, or a longer exposure duration than the first dose of EM radiation from the second light source, and at least one of the first light source and the second light source is an on-board metrology (OBM) device.

[0035]

[0038] 2. A method of producing a patterned photoresist on a substrate comprising: forming an unpatterned photoresist on a substrate; and exposing the unpatterned photoresist to a first dose of ultraviolet (UV) light using a first light source at a first location on the photoresist to create a patterned or partially patterned substrate, wherein the first dose of UV light lasts for about 1 millisecond or less; measuring optical properties of the photoresist at the first location; and exposing the patterned or partially patterned photoresist to a second dose of UV light at the first location on the photoresist, wherein the second dose of UV light has a larger wavelength, a larger pulse rate, or a longer exposure duration than the first dose of UV light from the first light source.

[0036]

[0039] 3. The method of example 2, wherein the second dose of EM radiation has one or more wavelengths greater than the first dose of EM radiation.

[0037]

[0040] 4. The method of example 2 or 3, wherein the first dose of EM radiation does not substantially change a measured optical property of the photoresist.

[0038]

[0041] 5. A method of producing a patterned photoresist on a substrate, comprising forming an unpatterned photoresist on a substrate; exposing the unpatterned photoresist to a first dose of electromagnetic (EM) radiation using a first light source at a first location on the unpatterned photoresist; measuring optical properties of the unpatterned photoresist; exposing the unpatterned photoresist to a second dose of EM radiation at the first location on the unpatterned photoresist to produce a patterned photoresist or a partially patterned photoresist; analyzing the optical properties of the patterned photoresist or the partially patterned photoresist as a function of the dose of EM radiation received; and analyzing the patterned photoresist or the partially patterned photoresist as a function of the dose of EM radiation received. 4. The method of claim 3, further comprising: exposing the patterned photoresist or partially patterned photoresist to a third dose of EM radiation with a first light source at a first location on the patterned photoresist or partially patterned photoresist, wherein the third dose of EM radiation is the same as the first dose of EM radiation; measuring an optical property of the patterned photoresist or partially patterned photoresist; and exposing the patterned photoresist or partially patterned photoresist to a fourth dose of EM radiation at the first location on the patterned photoresist or partially patterned photoresist, wherein the fourth dose of EM radiation is different from the second dose of EM radiation.

[0039]

[0042] 6. The method of example 5, wherein the fourth dose is selected based on a correlation of a measured difference in optical properties between the first dose of EM radiation and the third dose of EM radiation.

[0040]

[0043] 7. The method of any one of examples 1 to 6, wherein the first dose of EM radiation comprises ultraviolet (UV) light, X-rays, or extreme ultraviolet (EUV) light.

[0041]

[0044] 8. The method of any one of Examples 1 to 7, wherein the first light source and the second light source are one and the same.

[0042]

[0045] 9. The method of any one of Examples 1 to 8, wherein the first dose of EM radiation has a duration of 1 millisecond or less.

[0043]

[0046] 10. Analyzing optical properties of the patterned or partially patterned photoresist as a function of wavelength magnitude or duration of each dose of EM radiation received; exposing the patterned or partially patterned photoresist to a third dose of EM radiation with a first light source at a first location on the partially patterned photoresist, where the third dose of EM radiation is the same as the first dose of EM radiation; and 10. The method of any one of examples 1 to 9, further comprising: measuring an optical property of the turned photoresist or the partially patterned photoresist; and exposing the patterned photoresist or the partially patterned photoresist to a fourth dose of EM radiation at a first location on the photoresist to further pattern the partially patterned photoresist, wherein the fourth dose of EM radiation is different from the second dose of EM radiation.

[0044]

[0047] 11. The method of any one of Examples 1 to 10, wherein the first dose of EM radiation and the second dose of radiation have adjustable wavelengths and durations.

[0045]

[0048] 12. The method of any one of examples 1 to 11, wherein the unpatterned photoresist is a metal oxide photoresist.

[0046]

[0049] 13. The method of any one of Examples 1 to 12, wherein the unpatterned photoresist is formed on the substrate by a chemical vapor deposition (CVD) process or a spin-coating process.

[0047]

[0050] 14. The method of any one of examples 1 to 13, further comprising heating the patterned or partially patterned photoresist to a temperature in the range of about 30° C. to about 400° C. during a post-exposure bake and / or development process.

[0048]

[0051] 15. The method of any one of embodiments 1 to 14, wherein the measured optical property of the photoresist comprises thickness, surface roughness, chemical composition, complex dielectric constant, or complex refractive index.

[0049]

[0052] Although the above description is directed to an embodiment of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope of the present disclosure, the scope of the present disclosure being determined by the following claims. All documents described herein, including any priority documents and / or test procedures, are incorporated herein by reference, unless inconsistent with this text. As is apparent from the summary and specific embodiments set forth above, forms of the present disclosure have been illustrated and described, but various modifications may be made without departing from the nature and scope of the present disclosure. Thus, it is not intended that the present disclosure be limited to the forms of the present disclosure illustrated and described. Similarly, the term "comprising" is considered to be synonymous with the term "including" under the interpretation of US law. Similarly, whenever a composition, element, or group of elements is preceded by the transitional phrase "comprising," it is understood that the same composition or group of elements having the transitional phrase "consisting essentially of," "consisting of," "selected from the group of consisting of," or "is" prior to the recitation of such composition or one or more elements is also contemplated, and vice versa. As used herein, the term "about" refers to a + / - 10% variation from the nominal value. It is understood that such a variation can be included in any value provided herein.

[0050]

[0053] Certain embodiments and features are described using a set of numerical minimum values ​​and a set of numerical maximum values. It should be recognized that ranges including combinations of any two values ​​(e.g., any minimum value with any maximum value, any two minimum values, and / or any two maximum values) are envisioned unless otherwise indicated. Certain minimum values, maximum values, and ranges are set forth in one or more of the claims below.

Claims

1. 1. A method for producing a patterned photoresist on a substrate, comprising the steps of: forming an unpatterned photoresist on the substrate; exposing the unpatterned photoresist to a first dose of electromagnetic (EM) radiation using a first light source at a first location on the unpatterned photoresist; measuring an optical property of the unpatterned photoresist; and and exposing the unpatterned photoresist to a second dose of EM radiation at the first location on the unpatterned photoresist to create a patterned or partially patterned photoresist, wherein the second dose of EM radiation has a larger wavelength, a larger pulse rate, or a longer exposure duration than the first dose of EM radiation from a second light source, and at least one of the first light source and the second light source is an on-board metrology (OBM) device.

2. 10. The method of claim 1, wherein the first dose of EM radiation comprises ultraviolet (UV) light, x-rays, or extreme ultraviolet (EUV) light.

3. The method of claim 1 , wherein the first light source and the second light source are one and the same.

4. 10. The method of claim 1, wherein the first dose of EM radiation has a duration of 1 millisecond or less.

5. analyzing the optical properties of the patterned or partially patterned photoresist as a function of the wavelength magnitude or duration of each dose of received EM radiation; exposing the patterned photoresist or the partially patterned photoresist to a third dose of EM radiation with the first light source at the first location on the partially patterned photoresist, wherein the third dose of EM radiation is the same as the first dose of EM radiation; measuring the optical property of the photoresist; and exposing the patterned photoresist or the partially patterned photoresist to a fourth dose of EM radiation at the first location on the photoresist to further pattern the partially patterned photoresist, wherein the fourth dose of EM radiation is different from the second dose of EM radiation; The method of claim 1 further comprising:

6. 10. The method of claim 1, wherein the first dose of EM radiation and the second dose of radiation have tunable wavelengths and durations.

7. The method of claim 1 , wherein the unpatterned photoresist is a metal oxide photoresist.

8. The method of claim 1 , wherein the unpatterned photoresist is formed on the substrate by a chemical vapor deposition (CVD) process or a spin-coating process.

9. 10. The method of claim 1, further comprising heating the patterned photoresist or the partially patterned photoresist to a temperature in the range of about 30° C. to about 400° C. during a post-exposure bake and / or development process.

10. The method of claim 1 , wherein the measured optical properties of the photoresist include thickness, surface roughness, chemical composition, complex dielectric constant, or complex refractive index.

11. 1. A method for producing a patterned photoresist on a substrate, comprising the steps of: forming an unpatterned photoresist on the substrate; exposing the unpatterned photoresist to a first dose of ultraviolet (UV) light using a first light source at a first location on the photoresist to create a patterned or partially patterned substrate, wherein exposing the unpatterned photoresist to the first dose of UV light lasts for about 1 millisecond or less; Measuring an optical property of the photoresist at the first location; and and exposing the patterned photoresist or the partially patterned photoresist to a second dose of UV light at the first location on the photoresist, wherein the second dose of UV light has a larger wavelength, a larger pulse rate, or a longer exposure duration than the first dose of UV light from the first light source.

12. 12. The method of claim 11, wherein the second dose of EM radiation has one or more greater wavelengths than the first dose of EM radiation.

13. 12. The method of claim 11, wherein the first dose of EM radiation does not substantially change the measured optical property of the photoresist.

14. The method of claim 11 , wherein the unpatterned photoresist is a metal oxide photoresist.

15. The method of claim 11 , wherein the unpatterned photoresist is formed on the substrate by a chemical vapor deposition (CVD) process or a spin-coating process.

16. 12. The method of claim 11, further comprising heating the patterned photoresist or the partially patterned photoresist to a temperature in the range of about 30° C. to about 400° C. during a post-exposure bake and / or development process.

17. The method of claim 11 , wherein the measured optical properties of the photoresist include thickness, surface roughness, chemical composition, complex dielectric constant, or complex refractive index.

18. 1. A method for producing a patterned photoresist on a substrate, comprising the steps of: forming an unpatterned photoresist on a substrate; exposing the unpatterned photoresist to a first dose of electromagnetic (EM) radiation using a first light source at a first location on the unpatterned photoresist; measuring an optical property of the unpatterned photoresist; and exposing the unpatterned photoresist to a second dose of EM radiation at the first location on the unpatterned photoresist to create the patterned photoresist or the partially patterned photoresist; analyzing the optical properties of the patterned or partially patterned photoresist as a function of the dose of EM radiation received; exposing the patterned photoresist or the partially patterned photoresist to a third dose of EM radiation with the first light source at the first location on the patterned photoresist or the partially patterned photoresist, wherein the third dose of EM radiation is the same as the first dose of EM radiation; measuring the optical properties of the patterned or partially patterned photoresist; exposing the patterned photoresist or the partially patterned photoresist to a fourth dose of EM radiation at the first location on the patterned photoresist or the partially patterned photoresist, wherein the fourth dose of EM radiation is different from the second dose of EM radiation; A method comprising:

19. 20. The method of claim 18, wherein the fourth dose is selected based on a correlation of a measured difference in the optical property between the first dose of EM radiation and the third dose of EM radiation.

20. 20. The method of claim 19, wherein the unpatterned photoresist is a metal oxide photoresist, and the unpatterned photoresist is formed on the substrate by a chemical vapor deposition (CVD) process or a spin-coating process.

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