Reactive radical treatment for polymer removal and workpiece cleaning

A method for removing polymer is provided. An aqueous solution is applied to a semiconductor workpiece with polymer arranged thereon. The aqueous solution comprises an energy receiver configured to generate reactive radicals in response to energy. Energy is applied to the aqueous solution to generate the reactive radicals in the aqueous solution and to remove the polymer. A process tool for generating the reactive radicals is also provided.

BACKGROUND

During the manufacture of integrated circuits (ICs), multi-step sequences of semiconductor manufacturing processes are performed to gradually form electronic circuits on semiconductor workpieces. The semiconductor manufacturing processes may include, for example, ion implantation, plasma etching, and polymer cleaning. Polymer cleaning is a process for removing polymer used by or otherwise resulting from other semiconductor manufacturing processes, such as, for example, ion implantation and plasma etching. The polymer may include, for example, ion implanted photoresist and/or fluorocarbon polymer. One type of polymer cleaning process commonly used to remove polymer during front-end-of-line (FEOL) manufacturing is a sulfuric acid-hydrogen peroxide mixture (SPM) cleaning process.

DETAILED DESCRIPTION

Some sulfuric acid-hydrogen peroxide mixture (SPM) cleaning processes for removing polymer from a workpiece comprise applying a mixture of sulfuric acid solution and hydrogen peroxide solution to the polymer at high temperatures and with high concentrations of sulfuric acid. The high temperatures may, for example, exceed 100 degrees Celsius, and/or the high concentrations of sulfuric acid may, for example, exceed 85 percent by mass (wt %) in the sulfuric acid solution. The high temperatures and the high concentrations of sulfuric acid dissolve or detach the polymer, and the sulfuric acid solution and the hydrogen peroxide solution react to produce Caro's acid (e.g., peroxymonosulfuric acid). The Caro's acid and/or the hydrogen peroxide then react with the dissolved or detached polymer to oxidize the the polymer and to convert the polymer to water and carbon dioxide.

A challenge with the SPM cleaning processes is high thermal stress. Certain polymers, such as ion-implanted photoresist, induce stress on features under manufacture, such as fins of fin field-effect transistors (finFETs), and the high temperatures may exacerbate the stress. At small feature sizes, such as less than about 7 nanometers, features are weak and the high thermal stress may lead to a high likelihood of peeling and/or collapse. Further, to the extent that temperatures of the SPM cleaning processes are reduced, the solubility of the polymer and hence the cleaning efficiency reduces. Another challenge with the SPM cleaning processes is solubility and/or wettability. Certain polymers, such as ion-implanted photoresist and fluorocarbon polymer, have poor solubility and/or wettability in the mixture, such that cleaning efficiency may be low. Yet another challenge with the SPM cleaning processes is slow oxidation of the polymer, since Caro's acid is the dominant oxidant in the mixture.

The present application is directed towards a method for removing polymer using reactive radicals, as well as a process tool for performing the method. In some embodiments, an aqueous solution is applied to a semiconductor workpiece with polymer arranged thereon. The aqueous solution comprises an energy receiver configured to generate reactive radicals in response to energy. Energy is applied to the aqueous solution to generate the reactive radicals in the aqueous solution and to remove the polymer. Where the reactive radicals are hydroxyl radicals, the polymer may advantageously be removed at low temperatures, such as less than about 100 degrees Celsius. As such, thermal stress on the semiconductor workpiece is minimal, and the likelihood of feature collapse or peeling is minimal. Further, high concentrations of the hydroxyl radicals, such as greater than 1 part per million (ppm), advantageously increase solubility and/or wettability to the aqueous solution and/or other aqueous solutions, thereby promoting high cleaning efficiency.

With reference toFIGS. 1A-1C, a series of cross-sectional views100A-100C illustrate some embodiments of a method for removing polymer using reactive radicals.

As illustrated by the cross-sectional view100A ofFIG. 1A, one or more semiconductor manufacturing processes are performed to form polymer102over a semiconductor workpiece104. The polymer102may be, for example, ion-implanted photoresist, photoresist without ion implants, fluorocarbon polymer, and dry-etch-gas polymer. The semiconductor workpiece104comprises a semiconductor substrate and, in some embodiments, one or more additional layers and/or structures stacked thereover. The semiconductor substrate may be, for example, a bulk silicon substrate (e.g., of monocrystalline silicon), a germanium substrate, or a group III-V substrate.

In embodiments where the polymer102is photoresist with or without ion implants, the semiconductor manufacturing process(es) may, for example, comprise spin coating or otherwise depositing the polymer102and/or ion implantation into the polymer102. In embodiments where the polymer102is fluorocarbon polymer, the semiconductor manufacturing process(es) may, for example, comprise a dry etch using process gases with carbon and fluoride, such as carbon tetrafluoride. In embodiments where the polymer102is dry-etch-gas polymer, the semiconductor manufacturing process(es) may, for example, comprise dry etching.

As illustrated by the cross-sectional view100B ofFIG. 1B, a fluid106comprising reactive radicals108is generated and applied to the polymer102. In some embodiments, the fluid106has a concentration of reactive radicals greater than about 1 ppm, and/or the fluid106is an aqueous solution or steam. Further, in some embodiments where the fluid106is an aqueous solution, the fluid106has a temperature less than about 100 degrees Celsius, such as between 30-90 degrees Celsius. For example, the fluid106may be an aqueous solution with a temperature less than about 100 degrees Celsius, and/or a concentration of reactive radicals greater than about 1 ppm, at the surface of the polymer102. In alternative embodiments, stable radicals, such as TEMPO, may be employed in place of the reactive radicals108.

The reactive radicals108are highly reactive, oxidative, hydrophilic, or a combination the foregoing. For example, the reactive radicals108may be hydroxyl (OH) radicals. As another example, the reactive radicals108may be radicals that have a lifetime less than about 1 second and that have an oxidation potential greater than about 1.8 volts. The reactive radicals108react with and attach to the polymer102to modify the polymer102and to at least partially remove the polymer102from the semiconductor workpiece104. For example, the reactive radicals108may increase solubility of the polymer102, increase wettability of the polymer102, reduce internal stress or hardness of the polymer102, oxidize the polymer102, or a combination of the foregoing. The increase in solubility and/or wettability advantageously facilitates high cleaning efficiency, and/or the reduction in internal stress or hardness advantageously reduces the likelihood of feature collapse and/or peeling. Further, the increased solubility and/or oxidation advantageously facilitate removal of the polymer102.

In some embodiments, the fluid106is generated by applying energy to an aqueous solution with an energy receiver dissolved therein. The energy may be, for example, restricted so the aqueous solution remains in liquid form, or may alternatively be, for example, sufficient to gasify the aqueous solution. Further, the energy may, for example, be applied by sound waves, infrared radiation, heat, or ultraviolet (UV) radiation. The energy receiver is configured to generate the reactive radicals108in response to the energy, and is a chemical compound or molecule. For example, where the reactive radicals108are hydroxyl radicals, the energy receiver may be, for example, ozonated deionized water (e.g., DIO3) or hydrogen peroxide (e.g., H2O2). Further, the energy receiver may, for example, be dissolved in water (e.g., H2O), and/or may, for example, have a concentration ranging from 1 ppm to 30 wt %.

As illustrated by the cross-sectional view100C ofFIG. 1C, in some embodiments, an additional polymer cleaning process is performed on the semiconductor workpiece104to further remove the polymer102from the semiconductor workpiece104. For example, a wet cleaning solution or mixture110may be applied to the semiconductor workpiece104. The wet cleaning solution of mixture110may be, for example, an SPM for front-end-of-line (FEOL) cleaning and/or an organic solvent for back-end-of-line (BEOL) cleaning. As noted above, the reactive radicals108may be sufficient to remove the polymer102. However, to the extent that the reactive radicals108are insufficient and the additional polymer cleaning process is performed, the modification to the polymer102by the reactive radicals108aids the additional polymer cleaning process in removing the polymer102. For example, cleaning efficiency may be increased due to the increased wettability and/or the solubility of the polymer102. As another example, the likelihood of feature collapse and/or peeling may be reduced due to the reduced stress or hardness of the polymer102.

With reference toFIG. 2, a flowchart200of some embodiments of the method ofFIGS. 1A-1Cis provided.

At202, a semiconductor manufacturing process is performed to form polymer on a semiconductor workpiece. See, for example,FIG. 1A.

At204, hydroxyl radicals are generated and applied to the semiconductor workpiece to at least partially remove the polymer. See, for example,FIG. 1B. In some embodiments, the process for generating the hydroxyl radicals comprises applying at204aa fluid with an energy receiver to the semiconductor workpiece, where the energy receiver is configured to generate the hydroxyl radicals in response to energy. Further, in some embodiments, the process comprises applying at204benergy to the fluid to generate the hydroxyl radicals in the fluid.

At206, in some embodiments, an additional polymer cleaning process is performed to further remove the polymer. See, for example,FIG. 1C.

With reference toFIG. 3, a cross-sectional view300of some embodiments of a process tool for generating steam106awith reactive radicals108is provided. The process tool may, for example, be employed during a polymer cleaning process and/or to generate the fluid106ofFIGS. 1A-1C and 2. As illustrated, a housing302defines a process chamber304within which a workpiece support306is arranged. In some embodiments, the process chamber304has a controlled atmosphere differing from an ambient environment of the process tool. For example, the controlled atmosphere may have a different pressure and/or temperature than the ambient environment. The workpiece support306is configured to support a semiconductor workpiece104and, in some embodiments, to rotate the semiconductor workpiece104and/or to heat the semiconductor workpiece104.

The housing302comprises an inlet308and an outlet310that are laterally spaced and respectively arranged on the top and the bottom of the housing302. The inlet308is connected to a steam generator312and is configured to receive steam106awith reactive radicals108from the steam generator312. The steam106amay, for example, have a temperature less than about 100 degrees Celsius. Further, the reactive radicals108may, for example, have a concentration greater than about 1 ppm in the steam106a, and/or may be, for example, hydroxyl radicals. In some embodiments, the steam generator312is configured to generate the steam106aby gasifying or otherwise heating an aqueous solution with an energy receiver arranged therein. The energy receiver is configured to generate the reactive radicals108in response to energy and may be, for example, received from a solution source314. Where the reactive radicals108are hydroxyl radicals, the aqueous solution may be, for example, a hydrogen peroxide solution. The hydrogen peroxide solution may, for example, have a concentration of hydrogen peroxide between 1 ppm and 30 wt %. The outlet310is connected to an exhaust pump316configured to receive the steam106afrom the process chamber304after it flows over the semiconductor workpiece104.

Advantageously, as the steam106aand the reactive radicals108flow over the semiconductor workpiece104, the reactive radicals108react with and attach to polymer (not shown) on the semiconductor workpiece104to modify the polymer and to at least partially remove the polymer from the semiconductor workpiece104. For example, the reactive radicals108may increase solubility, increase wettability, reduce internal stress, or a combination of the foregoing. Modification of the polymer102advantageously facilitates high cleaning efficiency and/or reduces the likelihood of feature collapse and/or peeling.

With reference toFIGS. 4A and 4B, cross-sectional views400A,400B of some embodiments of a process tool for generating an aqueous solution106bwith reactive radicals108is provided. The process tool may, for example, be employed during a polymer cleaning process and/or to generate the fluid106ofFIGS. 1A-1C and 2.

As illustrated by the cross-sectional view400A ofFIG. 4A, a chemical delivery device402is configured to deliver or otherwise apply an aqueous solution106bto a semiconductor workpiece104and, in some embodiments, to generate or otherwise mix the aqueous solution. The aqueous solution106bcomprises an energy receiver (e.g., a chemical compound) configured to generate reactive radicals108in response to energy404, and the energy receiver may be or otherwise comprise, for example, ozonated deionized water or hydrogen peroxide to generate the reactive radicals108as hydroxyl radicals. In some embodiments, the chemical delivery device402is configured to apply the aqueous solution106bat a temperature less than about 100 degrees Celsius, such as between about 30-90 degrees Celsius, and/or is configured to apply the aqueous solution106bwith a concentration of energy receiver that is between about 1 ppm and 30 wt %. Further, in some embodiments, the chemical delivery device402is configured to apply additional aqueous solutions to the semiconductor workpiece104, such as those used by an RCA cleaning process.

An energy input device406is configured to apply the energy404to the aqueous solution106b, thereby generating the reactive radicals108in the aqueous solution106b. In some embodiments, the energy input device406applies the energy404with sufficient intensity and/or duration to generate the reactive radicals108with a concentration exceeding about 1 ppm in the aqueous solution106b. Further, in some embodiments, the energy input device406focuses the energy404towards the semiconductor workpiece104, so as to generate the reactive radicals108at the semiconductor workpiece104. The energy input device406may be, for example, an ultraviolet lamp configured to apply the energy404by way of UV radiation. Alternatively, the energy input device406may be, for example, a sonic transducer configured to apply the energy404by way of sound waves. Alternatively, the energy input device406may be, for example, a heater configured to apply the energy404by infrared radiation. In some embodiments, the heater is a resistive heater, and/or is configured to apply the infrared radiation to the aqueous solution106bwithout accompanying UV radiation or sound waves.

Advantageously, as the aqueous solution106band the reactive radicals108react with and attach to polymer (not shown) on the semiconductor workpiece104to modify the polymer and to at least partially remove the polymer from the semiconductor workpiece104. For example, the reactive radicals108may increase solubility, increase wettability, reduce internal stress, or a combination of the foregoing. Modification of the polymer102advantageously facilitates high cleaning efficiency and/or reduces the likelihood of feature collapse and/or peeling.

As illustrated by the cross-sectional view400B ofFIG. 4B, a housing408(partially shown) defines a cavity410within which a workpiece support306is arranged. The workpiece support306is configured to support a semiconductor workpiece104and, in some embodiments, to rotate the semiconductor workpiece104.

The energy input device406is arranged over the workpiece support306, proximate an opening in the housing408. Further, in some embodiments, the energy input device406fully covers the workpiece support306. The energy input device406comprises a body412supporting a UV lamp414therein, and further comprises a conduit416extending through the body412. The conduit416connects to the chemical delivery device402and provides the chemical delivery device402with a path for introducing the aqueous solution106bto the semiconductor workpiece104. In some embodiments, the conduit416is arranged at an axis of rotation for the workpiece support306, such that centrifugal force moves the aqueous solution106bto a periphery of the semiconductor workpiece104.

With reference toFIGS. 5-22, a series of cross-sectional and perspective views500-2200illustrate some embodiments of a method for manufacturing a finFET using reactive radicals for polymer cleaning. The polymer cleaning may, for example, be performed as described by the method ofFIGS. 1A-1C and 2, and/or the reactive radicals may, for example, be generated using the process tools ofFIGS. 3, 4A, and 4B.

As illustrated by the cross-sectional view500ofFIG. 5, a hard mask layer502is formed over a semiconductor substrate504. The hard mask layer502may, for example, be formed of silicon dioxide or silicon nitride, and/or the semiconductor substrate504may be, for example, a silicon substrate (e.g., a bulk monocrystalline silicon substrate), a germanium substrate, or a group III-V substrate. In some embodiments, the process for forming the hard mask layer502comprises depositing or otherwise growing the hard mask layer502over the semiconductor substrate504. For example, the hard mask layer502may be grown by thermal oxidation, or deposited by chemical or physical vapor deposition.

As illustrated by the cross-sectional view600ofFIG. 6, a first etch is performed into the hard mask layer502to pattern the hard mask layer502with a fin pattern for the finFET. The fin pattern may, for example, comprise one or more elongated features extending laterally in parallel. In some embodiments, the process for patterning the hard mask layer502comprises applying etchants602to the hard mask layer502, while a first photoresist layer604lithographically patterned with the fin pattern is in place. Further, in some embodiments, the process comprises removing or otherwise stripping the first photoresist layer604. The first photoresist layer604may, for example, be removed or otherwise stripped using the method ofFIGS. 1A-Cand2and/or using one of the process tools ofFIGS. 3, 4A, and 4B.

As illustrated by the cross-sectional view700ofFIG. 7, a second etch is performed into the semiconductor substrate504with the hard mask layer502in place. The second etch results in one or more fins702protruding upward from a base704of the semiconductor substrate504. Further, the second etch results in a first polymer by-product layer706lining the semiconductor substrate504. The first polymer by-product layer706may be, for example, fluorocarbon polymer or residue from dry etching gases. Further, while the first polymer by-product layer706is shown conformally lining the fin(s)702for ease of illustration, the first polymer by-product layer706may, for example, have length-wise discontinuities and/or non-uniformities in thickness. In some embodiments, the process for performing the second etch comprises applying an etchant708to the semiconductor substrate504. The etchant708may, for example, be applied according to a dry or plasma etch process and/or using, for example, a process gas comprising carbon and fluoride, such as carbon tetrafluoride (e.g., CF4).

As illustrated by the perspective view800ofFIG. 8, the fin(s)702resulting from the second etch extend laterally in parallel.

As illustrated by the cross-sectional view900ofFIG. 9, the first polymer by-product layer706(see, e.g.,FIGS. 7 and 8) is removed. In some embodiments, the removal process comprises, or is otherwise performed according to, the method ofFIGS. 1A-Cand2. For example, the removal process may comprise applying a fluid106with reactive radicals108, such as hydroxyl radicals, to the first polymer by-product layer706. Further, in some embodiments, the removal process is performed using one of the process tools ofFIGS. 3, 4A, and 4B.

As illustrated by the cross-sectional view1000ofFIG. 10, in some embodiments, a third etch is performed into the hard mask layer502(see, e.g.,FIG. 9) to remove the hard mask layer502. In some embodiments, the process for performing the third etch comprises applying an etchant1002that is selective of the hard mask layer502to the hard mask layer502. Further, in some embodiments, the process comprises removing etch residue using the method ofFIGS. 1A-Cand2, and/or using one of the process tools ofFIGS. 3, 4A, and 4B.

As illustrated by the cross-sectional view1100ofFIG. 11, a first dielectric layer1102is formed over the semiconductor substrate504and with an upper or top surface that is planar. The first dielectric layer1102may, for example, be formed as silicon dioxide, a low κ dielectric (i.e., a dielectric with a dielectric constant κ less than about 3.9), or phosphosilicate glass (PSG). In some embodiments, the process for forming the first dielectric layer1102comprises depositing or otherwise growing the first dielectric layer1102over the semiconductor substrate504. For example, the first dielectric layer1102may be grown by thermal oxidation or deposited by vapor deposition. Further, in some embodiments, the process comprises performing a planarization into the upper or top surface of the first dielectric layer1102. The planarization may, for example, be performed by a chemical mechanical polish (CMP).

As illustrated by the cross-sectional view1200ofFIG. 12, a fourth etch is performed into the first dielectric layer1102to recess the upper or top surface of the first dielectric layer1102to below an upper or top surface of the fin(s)702. In some embodiments, the process for performing the fourth etch comprises applying an etchant1202selective of the first dielectric layer1102to the first dielectric layer1102until the first dielectric layer1102is sufficiently etched back. Further, in some embodiments, the process comprises removing etch residue using the method ofFIGS. 1A-Cand2, and/or using one of the process tools ofFIGS. 3, 4A, and 4B.

As illustrated by the cross-sectional view1300ofFIG. 13, a second photoresist layer1302is formed masking a gate region of the finFET. In some embodiments, the process for forming the second photoresist layer1302comprises depositing the second photoresist layer1302and subsequently patterning the second photoresist layer1302using lithography. The second photoresist layer1302may, for example, be deposited by spin coating.

As illustrated by the perspective view1400ofFIG. 14, the second photoresist layer1302straddles the fin(s)702and extends laterally in a direction orthogonal to a length of the fin(s)702. Further, the second photoresist layer1302is laterally spaced from ends of the fin(s)702, along the length of the fin(s)702.

As illustrated by the cross-sectional view1500ofFIG. 15, ions1502are implanted into regions of the fin(s)702that are unmasked by the second photoresist layer1302to form source/drain regions1602(see, e.g.,FIG. 16) in the fin(s)702. Further, the ion implantation forms a second polymer by-product layer1504(e.g., a crust) along an outer surface of the second photoresist layer1302.

As illustrated by the perspective view1600ofFIG. 16, the source/drain regions1602are formed laterally spaced along the length of the fin(s)702, on opposite sides of the second polymer by-product layer1504.

As illustrated by the cross-sectional view1700ofFIG. 17, the second photoresist layer1302(see, e.g.,FIG. 15) and the second polymer by-product layer1504(see, e.g.,FIG. 16) are removed. In some embodiments, the removal process comprises, or is otherwise performed according to, the method ofFIGS. 1A-Cand2. For example, the removal process may comprise applying a fluid106with reactive radicals108to the second photoresist layer1302and the second polymer by-product layer1504. Further, in some embodiments, the removal process is performed using one of the process tools ofFIGS. 3, 4A, and 4B.

As illustrated by the perspective view1800ofFIG. 18, the source/drain regions1602are arranged on ends of the fin(s)702and laterally spaced by the gate region previously masked by the second photoresist layer1302(see, e.g.,FIG. 15).

As illustrated by the cross-sectional view1900ofFIG. 19, a second dielectric layer1902and a conductive layer1904are formed covering the fin(s)702. Further, the conductive layer1904is formed over the second dielectric layer1902and with an upper or top surface that is planar. The second dielectric layer1902may, for example, be formed of silicon dioxide, and/or the conductive layer1904may, for example, be formed of doped polysilicon or metal. In some embodiments, the process for forming the second dielectric layer1902and the conductive layer1904comprises sequentially depositing and/or growing the second dielectric layer1902and the conductive layer1904. The second dielectric layer1902and/or the conductive layer1904may, for example, be deposited or otherwise grown conformally and/or using thermal oxidation or vapor deposition. Further, in some embodiments, the process comprises performing a planarization into the upper or top surface of the conductive layer1904.

As illustrated by the perspective view2000ofFIG. 20, the second dielectric layer1902and the conductive layer1904cover the source/drain regions1602and the gate region previously masked by the second photoresist layer1302(see, e.g.,FIG. 15).

As illustrated by the cross-sectional view2100ofFIG. 21, a fifth etch is performed into the second dielectric layer1902(see, e.g.,FIG. 20) and the conductive layer1904(see, e.g.,FIG. 20) to form a gate electrode1904′ straddling the fin(s)702and electrically insulated from the fin(s)702by a gate dielectric layer1902′. In some embodiments, the process for forming the gate electrode1904′ and the gate dielectric layer1902′ comprises applying etchants2102to the conductive layer1904and the second dielectric layer1902, while a third photoresist layer2104lithographically patterned with a gate pattern is in place. Further, in some embodiments, the process comprises removing or otherwise stripping the third photoresist layer2104using the method ofFIGS. 1A-Cand2, and/or using one of the process tools ofFIGS. 3, 4A, and 4B.

As illustrated by the perspective view2200ofFIG. 22, the gate dielectric layer1902′ and the gate electrode1904′ are formed laterally between the source/drain regions1602, thereby defining a channel region along the length of the fin(s)702.

With reference toFIG. 23, a flowchart2300of some embodiments of the method ofFIGS. 5-22is provided.

At2302, a hard mask layer with a fin pattern is formed over a semiconductor substrate. See, for example,FIGS. 5 and 6.

At2304, a first etch is performed into the semiconductor substrate with the hard mask layer in place, such that a fin is formed according to the fin pattern and a first polymer by-product layer is formed lining the fin. See, for example,FIGS. 7 and 8.

At2306, reactive radicals, such as hydroxyl radicals, are applied to the first polymer by-product layer to remove the first polymer by-product layer. See, for example,FIG. 9.

At2308, a second etch is performed into the hard mask layer to remove the hard mask layer. See, for example,FIG. 10.

At2310, a first dielectric layer is formed laterally surrounding the fin with an upper or top surface recessed below that of the fin. See, for example,FIGS. 11 and 12.

At2312, a photoresist layer is formed covering a gate region of the fin. See, for example,FIGS. 13 and 14.

At2314, ion implantation is performed into regions of the fin unmasked by the photoresist layer, such that source/drain regions are formed in the fin and a second polymer by-product layer is formed on a surface of the photoresist layer. See, for example,FIGS. 15 and 16.

At2316, reactive radicals, such as hydroxyl radicals, are applied to the second polymer by-product layer and the photoresist layer to remove the second polymer by-product layer and the photoresist layer. See, for example,FIGS. 17 and 18.

At2318, a gate electrode is formed over the gate region of the fin. See, for example,FIGS. 19-22.

Thus, as can be appreciated from above, the present disclosure provides a first method for removing polymer. An aqueous solution is applied to a semiconductor workpiece with polymer arranged thereon. The aqueous solution comprises an energy receiver configured to generate hydroxyl radicals in response to energy. Energy is applied to the aqueous solution to generate the hydroxyl radicals in the aqueous solution and to remove the polymer.

In other embodiments, the present disclosure provides a process tool for removing polymer. A chemical delivery device is configured to apply an aqueous solution with an energy receiver to a semiconductor workpiece. The energy receiver is configured to generate hydroxyl radicals in response to energy. An energy input device is configured to apply energy to the energy receiver, while the chemical delivery device applies the aqueous solution to the semiconductor workpiece, to generate the hydroxyl radicals.

In yet other embodiments, the present disclosure provides a second method for removing polymer. A semiconductor manufacturing process is performed to form polymer on a semiconductor workpiece. A fluid with hydroxyl radicals is generated from ozonated deionized water or hydrogen peroxide. The fluid is applied to the semiconductor workpiece to remove the polymer from the semiconductor workpiece.