Method and apparatus for in-situ dry development

Abstract

An embodiment of an etching tool includes an etching chamber for plasma etching a first processed wafer, a transfer chamber coupled to the etching chamber, and a first travel path between the transfer chamber and the etching chamber, the first travel path including a path for moving the first processed wafer from the transfer chamber to the etching chamber, and the etching tool is configured to dry develop the first processed wafer before etching a hard mask on the first wafer in the etching chamber.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Non-Provisional Patent Application No. 17 / 950,001, filed September 21, 2022, which is incorporated herein by reference in its entirety.

[0002] The present invention relates generally to lithography, and in particular embodiments to a method and apparatus for in-situ dry development. [Background technology]

[0003] Semiconductor manufacturing involves several processing steps that involve forming patterns on a semiconductor substrate. These processing steps include, among other things, coating the surface of the substrate with photoresist, developing the latent image pattern, and transferring the pattern to the surface of the substrate by etching.

[0004] In a typical microfabrication process, a layer of photoresist is coated onto the working surface (upper surface) of a substrate, such as a semiconductor wafer. The photoresist is then patterned using photolithography to define a mask pattern, which is then transferred to an underlying layer by etching using the patterned resist as an etch mask. Photoresist patterning generally involves the steps of coating, exposing, and developing. The working surface of the substrate is coated with a film of photoresist. The photoresist is exposed through a lithography mask (and associated optics), for example, using extreme ultraviolet (EUV) lithography. Exposure with the pattern is followed by a development process, during which soluble regions of the photoresist are removed using either a wet (solvent) or dry (gaseous) development process. The soluble regions can be exposed or unexposed regions, depending on the photoresist tone and developer used.

[0005] Extreme ultraviolet (EUV) photolithography is a photolithography technique that uses photons in the extreme ultraviolet range (124 nm to 10 nm). Typically, a wavelength of 13.5 nm is used. EUV photoresists are generally metal-containing resists. Summary of the Invention [Means for solving the problem]

[0006] In one embodiment, an etching tool includes an etching chamber for plasma etching a first processed wafer, a transfer chamber coupled to the etching chamber, and a first travel path between the transfer chamber and the etching chamber, the first travel path including a path for moving the first processed wafer from the transfer chamber to the etching chamber, and the etching tool is configured to dry develop the first processed wafer before etching a hard mask on the first wafer in the etching chamber.

[0007] In one embodiment, a method for forming a patterned structure includes depositing a photoresist film on a hard mask material disposed on a semiconductor substrate, exposing the photoresist film to a pattern of extreme ultraviolet light to form an exposed photoresist film, loading the substrate into an apparatus capable of dry development and hard mask etching, dry developing the exposed photoresist film, and after dry development, etching the hard mask material in a hard mask etch chamber to form the patterned structure.

[0008] In one embodiment, a method for forming a patterned structure includes depositing a photoresist film on a hard mask material disposed on a semiconductor substrate, exposing the photoresist film to a pattern of extreme ultraviolet light to form an exposed photoresist film, wet developing the exposed photoresist film on a wet development track, loading the substrate into a processing apparatus configured for dry development and configured to plasma etch the hard mask, dry developing the exposed photoresist film to form a photoresist pattern, and etching the photoresist pattern into the hard mask material in a hard mask etch chamber to form the patterned structure.

[0009] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions which should be read in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a block diagram of a semiconductor device for in-situ developing and etching an EUV photoresist pattern, according to an embodiment. [Figure 2] FIG. 1 is a block diagram of a combined dry development and hard mask etch chamber, according to an embodiment. [Figure 3] FIG. 1 is a block diagram of a semiconductor device for in-situ developing and etching an EUV photoresist pattern, according to an embodiment. [Figure 4] FIG. 1 illustrates a block diagram of a hard mask etch chamber, according to an embodiment. [Figure 5] FIG. 2 is a block diagram of a plasma development chamber, according to an embodiment. [Figure 6] FIG. 2 is a block diagram of a chemical vapor development chamber, according to an embodiment. [Figure 7] FIG. 1 is a block diagram of a load lock chamber, according to an embodiment. [Figure 8]FIG. 1 is a block diagram of a semiconductor device for in-situ developing and etching an EUV photoresist pattern, according to an embodiment. [Figure 9] FIG. 2 is a block diagram of a combined load lock / plasma development chamber, according to an embodiment. [Figure 10] FIG. 2 is a block diagram of a combined load lock / chemical vapor development chamber, according to an embodiment. [Figure 11] FIG. 1 is a flow diagram illustrating the formation of an EUV photoresist pattern using hybrid dry / dry development and in-situ hardmask etching, according to an embodiment. [Figure 12] FIG. 1 is a flow diagram illustrating the formation of an EUV photoresist pattern using hybrid wet / dry development and in-situ hardmask etching, according to an embodiment. [Figure 13] FIG. 1 is a block diagram of a semiconductor device for in-situ developing and etching an EUV photoresist pattern, according to an embodiment. [Figure 14] FIG. 1 is a flow diagram illustrating the formation of an EUV photoresist pattern using hybrid wet / dry development and in-situ hardmask etching using a controller, according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] While the present invention has been described with reference to exemplary embodiments, this specification is not intended to be construed in a limiting sense. Various modifications and combinations of the exemplary embodiments, as well as other embodiments of the invention, will be apparent to those skilled in the art upon reading this specification. It is therefore intended that the appended claims cover any and all such modifications or embodiments.

[0012] EUV radiation and EUV photoresists behave differently than traditionally used deep ultraviolet (DUV) radiation and DUV photoresists. Therefore, different techniques are used in EUV lithography. EUV lithography enables higher patterning resolution capabilities. Consequently, feature sizes are becoming smaller and smaller with higher aspect ratios. To mitigate this trend, thinner photoresists have been used. However, etching transfer problems arise when the photoresist becomes too thin. Typically, the EUV photoresist pattern is first etched into a hard mask material to form a hard mask. The hard mask is then used to etch the pattern into the underlying substrate. However, the thin EUV photoresist pattern cannot withstand the long plasma etching process required to etch the EUV photoresist pattern into the underlying substrate.

[0013] Additionally, conventional EUV resists (non-metallic EUV resists) have relatively low EUV absorption, which leads to stochastic problems. The transition to metallic resists increases the etch resistance and EUV absorption (required for thinner thickness) during transfer to hard masks.

[0014] EUV resists can be wet developed using solvents or dry developed using gases. Conventional EUV photoresist development processes use a single wet development (or a single dry development) process to resolve the exposed latent image in the EUV photoresist.

[0015] Wet development processes inherently suffer from capillary forces caused by the surface tension of the liquid, which can lead to pattern distortion, pattern collapse, and other defects, especially in high aspect ratio areas with critical dimensions below 30 nm.

[0016] Dry development processes are not affected by such capillary forces and are therefore typically used for EUV photoresist patterns with features having widths of 30 nm or less.

[0017] Disclosed embodiments include tools and methods for dry developing an EUV photoresist pattern and in-situ etching the EUV photoresist pattern into a hardmask material to form a hardmask.

[0018] An etching tool configured to perform in-situ dry etching and hard mask etching of an EUV photoresist pattern on a semiconductor substrate, according to embodiments, is described with reference to Figures 1, 3, 8, and 13. The process flow for in-situ dry developing and hard mask etching of an EUV photoresist pattern is listed in the blocks of Figures 11, 12, and 14.

[0019] FIG. 1 is a block diagram of an etching tool 100 for in-situ dry developing an EUV photoresist pattern and then etching the EUV photoresist pattern into a hardmask material, according to an embodiment.

[0020] 1 includes a combined dry develop / hard mask etch chamber 108. The etch tool 100 includes a load lock chamber 106 attached to a transfer chamber 102 and the dry develop / hard mask etch chamber 108. The dry develop / hard mask etch chamber 108 is not fluidly coupled to (i.e., sealed from) the transfer chamber 102 after the wafer is transferred to the dry develop / hard mask etch chamber 108 for processing.

[0021] The load lock chamber 106 allows for the transfer of substrates, such as wafers, from another apparatus outside the etching tool 100 into the transfer chamber 102. A wafer transport arm 104 in the transfer chamber 102 can transport the wafer along a first travel path 110 from the load lock chamber 106 through the transfer chamber 102 to the development / hard mask etch chamber 108, and then back through the transfer chamber 102 to the load lock chamber once processing is complete. The first travel path 110 is shown in FIG. 1 by a dashed line.

[0022] A gas inlet 120 delivers a gas, such as air or nitrogen, to the transfer chamber 102. A vacuum port 122 in the transfer chamber 102, coupled to a vacuum pump (not shown), can evacuate the gas from the transfer chamber prior to loading or unloading a substrate from the load lock chamber 106 or to the dry develop / hard mask etch chamber 108.

[0023] FIG. 2 illustrates an integrated dry develop / hard mask etch chamber, according to an embodiment.

[0024] The dry develop / hard mask etch chamber 108 has a gas inlet 120 for filling the chamber with a bulk gas, such as helium, argon, or nitrogen, when a wafer is transferred into or out of the chamber. A vacuum port 122 connected to a vacuum pump (not shown) evacuates the chamber before dry develop and hard mask etch. The vacuum pump also removes process gases during processing. A wafer-in / wafer-out port 124 allows the wafer transfer arm 104 to load a wafer onto a wafer chuck 126 and remove the wafer from the wafer chuck 126 after processing. Hard mask etch gas can be delivered to the chamber through gas line 136. A dry developer gas can be delivered to the chamber through a separate developer gas line 132. The process gases can be directed into a showerhead 128 above the wafer chuck 126. Since at any given moment the dry develop / hard mask etch chamber 108 is being used for either etching or developing, in one or more embodiments the etch gas line 136 and the develop gas line 132 may be combined inside or outside the showerhead 128.

[0025] The showerhead 128 may be designed to distribute gases evenly across the wafer. A radio frequency (RF) power source 130 connected to an antenna 134 within the chamber provides RF power to initiate and maintain the plasma during the plasma development and hard mask etch processes. A DC voltage may be applied to bias the wafer chuck 126 to add sputtering during plasma development and hard mask etch.

[0026] 3 depicts an embodiment 101 of an etching tool for dry developing an EUV photoresist pattern and then etching it in-situ into a hard mask material. The etching tool 101 includes a dry developing chamber 112 and a hard mask etching chamber 114 separately mounted in a transfer chamber 102.

[0027] In this embodiment, the wafer transport arm 104 transports the wafer along the second travel path 116 during processing. The wafer transport arm 104 first moves the wafer from the load lock chamber 106 through the transfer chamber 102 to the dry develop chamber 112. After the dry develop process of the wafer is completed, the wafer transport arm 104 moves the wafer from the dry develop chamber to the hard mask etch chamber 114 along the second travel path 116. After the hard mask etch is completed, the wafer transport arm moves the wafer from the hard mask etch chamber 114 back to the load lock chamber 106 through the transfer chamber 102. The second travel path 116 is indicated by a dashed line in FIG. 3 .

[0028] The dry develop chamber 112 and the hard mask etch chamber 114 are not fluidly coupled to (i.e., sealed from) the transfer chamber 102 after a wafer has been transferred to either chamber for processing.

[0029] A hard mask etch chamber 114 configured for hard mask etching is illustrated in more detail in Figure 4. This chamber may be similar to the dry develop / hard mask etch chamber 108 of Figure 3, except that the dry develop gas line 132 may be eliminated.

[0030] In various embodiments, the dry development chamber 112 can be configured for a plasma development chamber 111 (FIG. 5) or a chemical vapor development chamber 113 (FIG. 6).

[0031] The plasma dry develop chamber 111 (FIG. 5) can be similar to the hard mask etch chamber 114, except that it is plumbed with a dry develop gas line 132 instead of a hard mask etch gas.

[0032] Chemical vapor development chamber 113 (FIG. 6) can be similar to plasma development chamber 111, but lacks RF power supply 130 and does not bias wafer chuck 126. For this and other reasons, chemical vapor development chamber 113 can be significantly less expensive than plasma development chamber 111.

[0033] The etching tool 101 of FIG. 3 can be less expensive if the dry develop chamber 112 is a chemical vapor develop chamber 113 instead of a plasma develop chamber 111 .

[0034] FIG. 7 illustrates a load lock chamber according to an embodiment.

[0035] The block diagram of FIG. 7 shows a typical load lock chamber 106 used to transfer boat loads of substrates, such as wafers, from the outside to the inside of a manufacturing tool, such as etching tools 100 (FIG. 1) and 101 (FIG. 3).

[0036] The load lock chamber 106 has a gas inlet 120 for filling the load lock chamber 106 with a bulk gas, such as air or nitrogen. A vacuum port 122 connected to a vacuum pump (not shown) allows the chamber to be evacuated before wafers are transferred from the load lock chamber 106 to the processing chambers in the etching tool 100. A large input port door 138 allows a boat load of wafers to enter the load lock chamber 106, and a large output port door 140 allows the wafer transport arm 104 to remove wafers from the boat and transfer them to the processing chambers in the etching tools 100 and 101.

[0037] In certain embodiments, the load lock chamber may be configured as a load lock / plasma development chamber or as a load lock / chemical vapor development chamber.

[0038] FIG. 8 illustrates an etching tool according to an embodiment.

[0039] In the etching tool 103 shown in FIG. 8, the load lock chamber is configured to perform a dry development process on the substrate or wafer before the substrate or wafer is transferred through the transfer chamber 102 to the hard mask etching chamber 114. The load lock / dry etching chamber 106 can be either a load lock / plasma developing chamber 107 ( FIG. 9 ) or a load lock / chemical vapor developing chamber 109 ( FIG. 10 ). The etching tool 103 of this embodiment, which has two processing chambers, is less expensive than the etching tool 101 of FIG. 3, which has three processing chambers. The third travel path 118 in the etching tool 103 is similar to the first travel path 110 in the etching tool 100 of FIG. 1 .

[0040] The loadlock / plasma development chamber 107 (FIG. 9) can be similar to the plasma development chamber 111 of FIG. 5, except that the loadlock / plasma development chamber 107 has both an input port door 138 for transferring wafers into the loadlock / plasma development chamber 107 at a time, and an output port door 140 for transferring wafers from the loadlock / plasma development chamber 107 to the transfer chamber 102. In contrast, the plasma development chamber 111 of FIG. 5 has a single wafer-in / wafer-out port 124.

[0041] Similarly, load lock / chemical vapor development chamber 109 (FIG. 10) can be similar to chemical vapor development chamber 113 of FIG. 6, except that load lock / chemical vapor development chamber 109 has both input 138 and output 140 port doors, whereas chemical vapor development chamber 113 of FIG. 6 has a single wafer-in / wafer-out port 124.

[0042] Dry development of EUV resist patterns can leave scumming or residue after development. This is particularly problematic for EUV photoresist patterns with geometries 30 nm wide or less. The hybrid wet / develop process described in co-pending U.S. patent application Ser. No. 17 / 943,729 (Attorney Docket No. TEL-210964US01) mitigates residue and scumming. The co-pending application is incorporated herein by reference in its entirety.

[0043] Figure 11 is a block flow diagram illustrating the major steps of a method for in-situ dry development and hard mask etching of an EUV photoresist pattern. The etching tools 100 and 101 of Figures 1 and 3 are used to illustrate the blocks of Figure 11.

[0044] A substrate having an EUV photoresist pattern on a hard mask material on the substrate is provided in block 161. The substrate may be loaded into a load lock chamber shown in Figures 1, 3, or 8-10 at this stage of processing.

[0045] The substrate may include the layer to be etched and, in various embodiments, may have device regions formed in the layer. The substrate may be a semiconductor wafer such as a silicon wafer or a gallium arsenide wafer, a chromium or other layer on a lithographic reticle, or a layer such as silicon dioxide, silicon nitride, titanium, titanium nitride, or copper overlying a base substrate structure.

[0046] Generally, as used herein, "substrate" refers generally to an object to be processed. A substrate may include any material portion of a device, particularly a semiconductor device or other electronic device structure, and may be, for example, a base substrate structure such as a semiconductor wafer, a lithographic reticle, or a layer on or overlying the base substrate structure, e.g., a thin film. Thus, substrate is not limited to any particular base structure, patterned or unpatterned underlying layer, or overlying layer, but is intended to include any such layer or base structure, and any combination of multiple layers and / or base structures. While particular types of substrates may be referenced herein, this is for illustrative purposes only.

[0047] Embodiments may be implemented in a manufacturing facility having different types of etch tools. In block 162 of Figure 11, the process determines whether the etch tool needs to perform the dry develop and hard mask etch processes in the same chamber as in Figure 1 or in a different chamber than in Figure 3. If the etch tool includes an integrated dry develop and hard mask etch chamber (as in Figure 1), the substrate is transferred from the load lock chamber to the dry develop and hard mask etch chamber, as shown in the first travel path through the transfer chamber.

[0048] The etching tool 100 of FIG. 1 will be used to explain blocks 164, 166, and 168 of FIG.

[0049] In block 164 of FIG. 11, the substrate may be loaded into the dry develop / hard mask etch chamber 108 of the etch tool 100.

[0050] In block 166 of FIG. 11, one or more dry development processes may be performed to produce structures having target critical dimensions.

[0051] In block 168 of FIG. 11, a hard mask etch process may be performed in the same chamber 108 in which the dry development process is performed.

[0052] On the other hand, if the hard mask etch process is performed in a separate chamber, the substrate is transferred from the load lock chamber of FIG. 3 to the dry development of the etch tool 101 (block 170).

[0053] Blocks 170, 172, 174, and 176 of FIG. 11 will be explained using the etching tool 101 of FIG.

[0054] 11, the substrate may be transferred to the dry develop chamber 112 in the etching tool 101. In the case of the etching tool 103 (FIG. 8), the substrate may be held in the integrated load lock and dry develop chamber 107 / 109.

[0055] In block 172 of FIG. 11, the EUV photoresist pattern may be dry developed in the dry development chamber 112 .

[0056] In block 174 of FIG. 11, the substrate may be transferred from the dry develop chamber 112 to the hard mask etch chamber 114.

[0057] In block 176 of FIG. 11, the EUV photoresist pattern can be transferred to the hard mask material using an anisotropic etch in the hard mask etch chamber 114.

[0058] Figure 12 is a block flow diagram illustrating the major steps of a method for hybrid wet / dry developing an EUV photoresist pattern. The hybrid wet development and in-situ dry development / hard mask etch system 160 of Figure 13 is used to illustrate the blocks of Figure 12.

[0059] The hybrid wet development and in-situ dry development / hard mask etch system 160 of Figure 13 includes a wet development track 142 coupled to an etch tool 105. The etch tool 105 is configured to perform both a dry development process and a hard mask etch process in-situ. In Figure 13, the etch tool 105 is also configured with an optional bake chamber 146 and a blanket UV exposure chamber 148.

[0060] The hybrid wet develop and in-situ dry develop / hard mask etch system 160 may also include a parameter measurement tool 144. For example, the parameter measurement tool 144 may be a CD metrology tool. The parameter measurement tool 144 may be on a track or stand-alone. A controller 150 may be coupled to the parameter measurement tool 144 and to the dry develop / hard mask etch chamber 108 or other processing chambers. The controller 150 may collect 154 parameter measurement data, compare the parameter data with parameter specifications, generate control signals, and send the control signals 152 to microcontrollers in the dry develop / hard mask etch chamber 108 and other processing chambers to adjust process recipes, such as dry develop recipes and bake recipes, so that the structures in the EUV photoresist pattern meet the parameter specifications and the uniformity specifications across the wafer after processing.

[0061] The EUV photoresist pattern is partially wet developed in block 180 of Figure 12. After the partial wet development, the width of the structures in the EUV photoresist pattern is larger than the target CD.

[0062] In block 182 of FIG. 12, the substrate with the partially wet-developed EUV photoresist pattern is transferred from the wet development track 142 to the etching tool 105 of FIG.

[0063] In block 184 of Figure 12, the EUV photoresist pattern may optionally undergo a thermal treatment in a bake chamber 146 in the etching tool 105 of Figure 13. Alternatively, the EUV photoresist pattern may optionally undergo a blanket UV radiation exposure in a blanket UV exposure chamber 148. The thermal treatment process and the blanket UV exposure process are typically performed to increase cross-linking in the exposed EUV photoresist to enhance pattern strength, alter the EUV photoresist development rate, and improve line edge roughness (LER).

[0064] In block 186 of FIG. 12, after wet development of the EUV photoresist pattern on the wet development track 142, the substrate may be transported through the load lock chamber 106, through the transfer chamber 102 and into the dry development / hard mask etch chamber 108 of the etch tool 105.

[0065] In blocks 188 and 190 of Figure 12, a dry develop process and a hard mask etch process are performed sequentially in the dry develop / hard mask etch chamber 108. A fourth travel path 156, shown in dashed lines in Figure 13, is similar to the second travel path 116 of Figure 2. The fourth travel path 156 varies depending on whether a blanket UV exposure process was performed in the blanket UV exposure chamber 148 or whether a thermal treatment process was performed in the bake chamber 146.

[0066] FIG. 14 is a block flow diagram illustrating the major steps of a method for hybrid wet / dry developing EUV photoresist patterns, including the use of sensors to measure pattern parameters and a controller to generate control signals and control subsequent processes.

[0067] The hybrid wet development and in-situ dry development / hard mask etch system 160 of FIG. 13 is used to illustrate the blocks of FIG.

[0068] In block 200 of FIG. 14, the EUV photoresist pattern may be partially developed on a wet development track 142, such as in the hybrid wet development and in-situ dry development / hard mask etch system 160 of FIG.

[0069] In block 202 of FIG. 14, a sensor in the parameter measurement tool 144 of FIG. 13 measures a parameter of a feature of the EUV photoresist pattern. An exemplary sensor may be a CD measurement sensor. The CD measurement sensor may measure local CD on one particular structure or may measure CD uniformity across the wafer on several structures. Another exemplary sensor may be an optical sensor that measures a monomer concentration parameter in exposed and / or unexposed EUV photoresist locally or across the wafer. Another exemplary sensor may be a thermal sensor that measures a temperature parameter of the EUV photoresist locally or across the wafer. Another exemplary sensor may be a thickness sensor that measures a thickness parameter of the EUV photoresist locally or across the wafer. Parameter measurement data from one or more of these sensors may be collected by the controller 150.

[0070] In block 204 of FIG. 14 , the controller 150 can be programmed to generate control signals that can control processes during the EUV photoresist pattern development process and the hard mask etch process. For example, a dry development control signal 152 can be generated and sent to the dry development / hard mask etch chamber 108 to adjust the dry development recipe so that the structures in the EUV photoresist pattern meet the target CD specifications after development. For example, a thermal treatment signal or blanket UV exposure control signal can be generated and sent to the bake chamber 146 or the blanket UV exposure chamber 148 to adjust the thermal treatment recipe or blanket UV exposure recipe to produce the target critical dimensions and improve across-wafer uniformity. For example, a hard mask etch control signal can be generated and sent to the dry development / hard mask etch chamber 108 to adjust the hard mask etch recipe to produce the target critical dimensions and improve across-wafer uniformity.

[0071] In block 206 of FIG. 14, after wet development or parameter measurement, the substrate is loaded into the etching tool 105 of FIG.

[0072] An optional thermal treatment or blanket UV exposure may be performed in block 208 of Figure 14. Thermal treatment or blanket UV exposure control signals sent from controller 150 may adjust the thermal treatment or blanket UV exposure recipe for each wafer to produce target critical dimensions and improve across-wafer uniformity across all wafers.

[0073] In block 210 of FIG. 14, the substrate is loaded into the dry develop / hard mask etch chamber 108 of the etching tool 105 of FIG.

[0074] 14, a dry develop process may be performed in the dry develop / hard mask etch chamber 108. Dry develop control signals sent from the controller 150 may adjust the dry develop recipe for each wafer to produce target critical dimensions and improve across-wafer uniformity across all wafers.

[0075] 14, a hard mask etch process may also be performed in the dry develop / hard mask etch chamber 108. Hard mask etch control signals sent from the controller 150 may adjust the hard mask etch recipe for each wafer to produce target critical dimensions and improve across-wafer uniformity across all wafers.

[0076] Embodiments of an etch tool that performs dry development and hard mask etching in-situ reduce cycle time and tool costs, thereby reducing manufacturing costs. In embodiments, the etch tool has a hard mask etch chamber and a dry development chamber on the same etch tool platform. In other embodiments, the dry development process and the hard mask etch process may be performed in the same chamber, reducing tool costs. In embodiments, the dry development process may be performed in a load lock chamber.

[0077] As discussed above, in one embodiment, the etch tool has separate dry development etch chambers and hard mask etch chambers. In another embodiment, the hard mask etch chamber is also configured for dry development. In one embodiment, the dry development chamber is a chemical vapor development chamber. In another embodiment, the dry development chamber is a plasma development chamber. In another embodiment, the load lock chamber also serves as the dry development chamber. In other embodiments, a bake chamber or blanket UV exposure chamber is included in the etch tool.

[0078] In another embodiment, the dry development process and the hard mask etch process are performed sequentially in the same plasma etch chamber. In one embodiment, the dry development process is a chemical vapor development process and the hard mask etch process is a plasma etch process. In another embodiment, the dry development process is a plasma development process and the hard mask etch process is a plasma etch process. In other embodiments, the substrate undergoes baking or is treated with a blanket UV exposure prior to the dry development process.

[0079] In another embodiment, the EUV photoresist pattern is partially developed using a wet development step and then transferred to an embodiment of an etching tool configured for dry development and hard mask etching. After the initial partial development, the width of the target structures in the EUV photoresist pattern is larger than the target critical dimension (CD) specification. After the dry development process and before the hard mask etching, the width of the target structures may be equal to the critical dimension CD specification.

[0080] In another embodiment, sensors measure parameters of the EUV photoresist pattern and send the data to a controller coupled to the dry develop chamber and possibly other process chambers, which can be programmed to generate control signals that make adjustments to the dry develop recipe and possibly other process recipes, such as bake recipes, to produce target critical dimensions and improve uniformity across the wafer.

[0081] Thus, various embodiments enable improved development of extreme ultraviolet photoresist films while reducing manufacturing costs.

[0082] Illustrative embodiments of the present invention are summarized here, although other embodiments may be understood from the entire specification and claims appended hereto.

[0083] Example 1. An etching tool includes an etching chamber for plasma etching a first processed wafer, a transfer chamber coupled to the etching chamber, and a first travel path between the transfer chamber and the etching chamber, the first travel path including a path for moving the first processed wafer from the transfer chamber to the etching chamber, and the etching tool is configured to dry develop the first processed wafer before etching a hard mask on the first wafer in the etching chamber.

[0084] Example 2. The etching tool of Example 1, further comprising: a dry development chamber coupled to the transfer chamber for developing a photoresist layer on the first processed wafer; and a second travel path between the transfer chamber and the dry development chamber, the second travel path including a path for moving the first processed wafer from the transfer chamber to the dry development chamber and from the dry development chamber to the etching chamber.

[0085] Example 3. The etching tool of Example 1 or 2, further comprising a load lock chamber coupled to the transfer chamber for transferring the first wafer between another apparatus and the transfer chamber.

[0086] Example 4. The etching tool of any one of Examples 1-3, wherein the load lock chamber is configured to dry develop a photoresist layer on the first processed wafer.

[0087] Example 5. The etching tool of any one of Examples 1-4, wherein the etching chamber is configured to dry develop a photoresist layer on the first processed wafer. 6. The etching tool of any one of Examples 1-4, wherein the etching chamber is configured to dry develop a photoresist layer and to plasma etch a hard mask on the first wafer.

[0088] Example 7. The etching tool of any one of Examples 1-6, further comprising an ultraviolet (UV) chamber for exposing the first wafer to UV light.

[0089] Example 8. The etching tool of any one of Examples 1-7, further comprising a bake chamber for heat treating the first wafer.

[0090] Example 9. The etching tool of any one of Examples 1-8, wherein the transfer chamber is coupled to a vacuum system.

[0091] Example 10. The etching tool of any one of Examples 1-9, further comprising a measurement sensor for measuring parameters of features of the photoresist layer on the first wafer prior to dry developing, and a controller programmed to generate control signals for controlling a subsequent process for dry developing based on the parameters.

[0092] Example 11. A method for forming a patterned structure in a hard mask, the method comprising: depositing a photoresist film on a hard mask material on a working surface of a semiconductor substrate; exposing the photoresist film to a pattern of extreme ultraviolet light to form an exposed photoresist film; loading the substrate into an apparatus capable of dry development and hard mask etching; dry developing the exposed photoresist film; and after dry development, etching the hard mask material in a hard mask etch chamber to form the patterned structure.

[0093] Example 13. The method of example 11 or 12, wherein the dry development and hard mask etching are performed sequentially in a hard mask etch chamber.

[0094] Example 14. The method according to any one of Examples 11-13, wherein the dry development is a chemical vapor etching development using hydrogen chloride gas or hydrogen bromide gas.

[0095] Example 15. The method according to any one of Examples 11 to 14, wherein the dry development is a plasma etching development using hydrogen bromide gas and argon gas.

[0096] Example 16. The method of any one of Examples 11-15, further comprising blanket exposing the substrate to UV light prior to dry developing.

[0097] Example 17. A method for forming a pattern includes depositing a photoresist film on a hard mask material disposed on a semiconductor substrate, exposing the photoresist film to a pattern of extreme ultraviolet light to form an exposed photoresist film, wet developing the exposed photoresist film on a wet development track, loading the substrate into a processing apparatus configured for dry development and configured for plasma etching, dry developing the exposed photoresist film to form a photoresist pattern, and etching the photoresist pattern into the hard mask material in a hard mask etch chamber to form a patterned structure.

[0098] Example 18. The method of claim 17, wherein wet development comprises using 0% to 10% acetic acid, propylene glycol methyl ether acetate, and methyl isobutyl carbinol, or a combination thereof.

[0099] Example 19. The method of example 17 or 18, wherein the dry development is a chemical vapor etching development using hydrogen chloride or hydrogen bromide.

[0100] Example 20. The method of example 17 or 18, wherein the dry development is plasma etch development using hydrogen chloride, hydrogen bromide, argon, helium, or a combination thereof.

[0101] Example 21. The method of any one of Examples 17-20, further comprising: after wet developing, measuring critical dimensions on the photoresist pattern and collecting critical measurement data; transmitting the critical dimension data to a controller coupled to the dry developing chamber; and the controller adjusting the dry developing recipe to reach the target critical dimensions after dry developing.

[0102] Example 22. The method of any one of Examples 17-21, further comprising blanket exposing the photoresist film to UV light prior to dry developing.

[0103] While the present invention has been described with reference to exemplary embodiments, this specification is not intended to be construed in a limiting sense. Various modifications and combinations of the exemplary embodiments, as well as other embodiments of the invention, will be apparent to those skilled in the art upon reading this specification. It is therefore intended that the appended claims cover any and all such modifications or embodiments.

Claims

1. 1. An etching tool comprising: an etching chamber for plasma etching a first processed wafer; a transfer chamber coupled to the etching chamber; a first travel path between the transfer chamber and the etching chamber, the first travel path having a path for moving the first processed wafer from the transfer chamber to the etching chamber; and The etching tool is configured to dry develop the first processed wafer prior to etching a hard mask on the first wafer in the etching chamber.

2. moreover, a dry development chamber coupled to the transfer chamber for developing a photoresist layer on the first processed wafer; a second travel path between the transfer chamber and the dry developing chamber, the second travel path having a path for moving the first processed wafer from the transfer chamber to the dry developing chamber and from the dry developing chamber to the etching chamber; The etching tool of claim 1 , comprising:

3. moreover, The etching tool of claim 1 , further comprising a load lock chamber coupled to the transfer chamber for transferring the first wafer between another apparatus and the transfer chamber.

4. The etching tool of claim 3 , wherein the load lock chamber is configured to dry develop a photoresist layer on the first processed wafer.

5. The etching tool of claim 1 , wherein the etching chamber is configured to dry develop a photoresist layer on the first processed wafer.

6. 10. The etching tool of claim 1, wherein the etching chamber is configured to dry develop a photoresist layer and plasma etch a hard mask on the first wafer.

7. The etching tool of claim 1 , further comprising an ultraviolet (UV) chamber for exposing the first wafer to UV light.

8. The etching tool of claim 1 , further comprising a bake chamber for heat treating the first wafer.

9. The etching tool of claim 1 , wherein the transfer chamber is coupled to a vacuum system.

10. moreover, a measurement sensor that measures parameters of features in a photoresist layer on the first wafer before the dry developing; a controller programmed to generate control signals for controlling a subsequent process for the dry development based on the parameters; The etching tool of claim 1 , comprising:

11. 1. A method for forming a patterned structure, comprising: depositing a photoresist film on a hard mask material disposed over a semiconductor substrate; exposing the photoresist film to a pattern of extreme ultraviolet light to form an exposed photoresist film; loading the substrate into an apparatus capable of dry development and hard mask etching; dry developing the exposed photoresist film; After the dry developing step, etching the hard mask material in a hard mask etching chamber to form the patterned structure; A method comprising:

12. the dry developing step is performed in a dry developing chamber; 12. The method of claim 11, wherein the hard mask etch is performed in the hard mask etch chamber.

13. 12. The method of claim 11, wherein the dry developing and the hard mask etching are performed sequentially in the hard mask etching chamber.

14. 12. The method according to claim 11, wherein the dry development is a chemical vapor etching development process using hydrogen chloride gas or hydrogen bromide gas.

15. 12. The method of claim 11, wherein the dry development is a plasma etching development process using hydrogen bromide gas and argon gas.

16. moreover, 12. The method of claim 11, further comprising the step of blanket exposing the substrate to UV light before the step of dry developing.

17. 1. A method for forming a patterned structure, comprising: depositing a photoresist film over a hard mask material disposed on a semiconductor substrate; exposing the photoresist film to a pattern of extreme ultraviolet light to form an exposed photoresist film; wet developing the exposed photoresist film on a wet development track; loading the substrate into a processing apparatus configured for dry development and configured for plasma etching; dry developing the exposed photoresist film to form a photoresist pattern; etching the photoresist pattern into the hard mask material in a hard mask etch chamber to form the patterned structure; A method comprising:

18. 18. The method of claim 17, wherein the wet developing step comprises using 0% to 10% acetic acid, propylene glycol methyl ether acetate, and methyl isobutyl carbinol, or a combination thereof.

19. 18. The method of claim 17, wherein the dry development is a chemical vapor etching development comprising using hydrogen chloride or hydrogen bromide.

20. 18. The method of claim 17, wherein the dry development is a plasma etch development using hydrogen chloride, hydrogen bromide, argon, helium, or a combination thereof.

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