KR20210130247A - Method of Growing Thick Oxide Films at Low Temperature Thermal Oxide Quality - Google Patents

Abstract

Implementations described herein generally relate to methods for forming a low-k dielectric material on a semiconductor substrate. More specifically, implementations described herein relate to methods of forming a silicon oxide film at high pressures and low temperatures. A method of forming a silicon oxide film includes loading a substrate having a silicon-containing film formed thereon into a processing region of a high-pressure vessel. The method further includes forming a silicon oxide film on the silicon-containing film. The step of forming a silicon oxide film on the silicon-containing film includes exposing the silicon-containing film to an oxidizing medium comprising an amine additive at a pressure greater than about 1 bar, and subjecting the high pressure vessel to a temperature of from about 100°C to about 550°C. including maintaining.

Description

Method of Growing Thick Oxide Films at Low Temperature Thermal Oxide Quality

[0001] Embodiments described herein generally relate to methods for forming low-k dielectric material on a semiconductor substrate. More specifically, the embodiments described herein relate to methods of forming a silicon oxide film at high pressure and low temperature using an oxidative medium including an additive.

[0002] The formation of semiconductor devices, such as memory devices, logic devices, microprocessors, etc., involves depositing low-k dielectric films over semiconductor substrates. Low-k dielectric films are used to make circuits for manufacturing devices. Current dry or wet silicon oxidation techniques are usually performed at temperatures above 800°C. However, materials deposited on semiconductor substrates may not withstand temperatures in excess of 800°C. As a result, low-k dielectric films may not be deposited at temperatures higher than the thermal budget of 800° C., and films deposited within the thermal budget usually suffer from poor quality. Additionally, current dry or wet silicon oxidation techniques cannot deposit quality low-k dielectric films having a thickness greater than 100 angstroms.

[0003] Accordingly, there is a need for a method of depositing high quality low-k dielectric films at temperatures that meet thermal budget targets.

[0004] Embodiments described herein generally relate to methods for forming a low-k dielectric material on a semiconductor substrate. More specifically, embodiments described herein relate to methods of forming a silicon oxide film at high pressures and low temperatures. A method of forming a silicon oxide film includes loading a substrate having a silicon-containing film formed thereon into a processing region of a high-pressure vessel. The method further includes forming a silicon oxide film on the silicon-containing film. The step of forming a silicon oxide film on the silicon-containing film includes exposing the silicon-containing film to an oxidizing medium comprising an amine additive at a pressure greater than about 1 bar, and subjecting the high pressure vessel to a temperature of from about 100°C to about 550°C. including maintaining.

[0005] A method of forming a silicon oxide film includes loading a substrate having a silicon-containing film deposited thereon into a processing region of a high-pressure vessel, and forming a silicon oxide film on the silicon-containing film. The step of forming a silicon oxide film on the silicon-containing film includes exposing the silicon-containing film to an oxidizing medium comprising an amine additive at a pressure greater than about 1 bar, and subjecting the high pressure vessel to a temperature of from about 100°C to about 550°C. including maintaining.

[0006] A method of forming a conformal silicon oxide film includes depositing a silicon-containing film on a substrate including a plurality of vias. A silicon-containing film is deposited over the plurality of vias and each exposed surface of the substrate. The method further includes loading a substrate having a silicon-containing film deposited thereon into a processing region of a high-pressure vessel, and forming a conformal silicon oxide film on the silicon-containing film. Forming the conformal silicon oxide film on the silicon-containing film comprises exposing the silicon-containing film to an oxidizing medium comprising an amine additive, wherein the oxidizing medium comprises from about 1,000 ppm to about 20,000 ppm of an amine additive; and maintaining the high pressure vessel at a temperature of about 100° C. to about 550° C. and a pressure of about 1 bar to about 65 bar.

[0007] A method of forming a silicon oxide film includes loading a substrate having a silicon-containing film deposited thereon into a processing region of a high-pressure vessel, and forming a silicon oxide film on the silicon-containing film. Forming the silicon oxide film on the silicon-containing film comprises exposing the silicon-containing film to an oxidizing medium comprising ammonia, the oxidizing medium selected from the group of steam, oxygen, and peroxide, and subjecting a high pressure vessel to about maintaining a temperature of from 400° C. to about 505° C. and a pressure greater than about 10 bar. The silicon oxide film has a uniform thickness of from about 100 angstroms to about 400 angstroms.

[0008] In such a way that the above-listed features of the present disclosure may be understood in detail, a more specific description of the present disclosure, briefly summarized above, may be made with reference to embodiments, some of which are appended It is illustrated in the drawings. It should be noted, however, that the appended drawings illustrate only exemplary embodiments and are not to be regarded as limiting the scope of the disclosure, but may admit to other equally effective embodiments.
1 depicts a simplified front cross-sectional view of an example of a high pressure vessel that may be used to practice one or more implementations described herein.
2A illustrates a semiconductor device having a silicon-containing film deposited thereon, in accordance with embodiments disclosed herein.
2B-2D illustrate various views of a semiconductor device having a conformal uniform silicon oxide film formed thereon, in accordance with embodiments disclosed herein.
3 is a flowchart illustrating a method of forming a conformal silicon oxide film according to one embodiment.
To facilitate understanding, like reference numbers have been used where possible to designate like elements that are common to the drawings. It is contemplated that elements and features of one embodiment may be beneficially incorporated into other embodiments without further recitation.

[0014] Embodiments described herein generally relate to methods for forming a low-k dielectric material on a semiconductor substrate. More specifically, embodiments described herein relate to methods of forming a silicon oxide film at high pressures and low temperatures. A method of forming a silicon oxide film includes loading a substrate having a silicon-containing film formed thereon into a processing region of a high-pressure vessel. The method further includes forming a silicon oxide film on the silicon-containing film. The step of forming a silicon oxide film on the silicon-containing film includes exposing the silicon-containing film to an oxidizing medium comprising an amine additive at a pressure greater than about 1 bar, and subjecting the high pressure vessel to a temperature of from about 100°C to about 550°C. including maintaining.

[0015] Implementations described herein will be described below with reference to a high pressure oxidation process that may be performed using a high pressure oxidation system. The device description set forth in FIG. 1 herein is exemplary and should not be construed or construed as limiting the scope of the embodiments described herein.

1 is a simplified front cross-sectional view of a high pressure vessel 100 for a high pressure annealing process. The high pressure vessel 100 has a body 110 having an inner surface 113 and an outer surface 112 surrounding a processing region 115 . In some implementations, such as in FIG. 1 , the body 110 has an annular cross-section, although in other implementations, the cross-section of the body 110 may be rectangular or any closed shape. The outer surface 112 of the body 110 may be made of corrosion resistant steel (CRS), such as, but not limited to, stainless steel. In one implementation, the inner surface 113 of the body 110 is made of nickel-base steel alloys exhibiting high corrosion resistance, such as, but not limited to, ^{Hastelloy ® .}

[0017] The high pressure vessel 100 has a door 120 configured to sealably surround a processing region 115 within the body 110 , such that the processing region 115 can be accessed when the door 120 is opened. The high pressure seal 122 is utilized to seal the door 120 against the body 110 to seal the processing region 115 for processing. The high pressure seal 122 may be made of a polymer such as, but not limited to, a perfluoroelastomer. A cooling channel 124 is disposed on the door 120 adjacent the high pressure seal 122 to maintain the high pressure seal 122 below the maximum safe-operating temperature of the high pressure seal 122 during processing. . A coolant such as, but not limited to, an inert, dielectric, and/or high performance heat transfer fluid circulates within the cooling channel 124 to maintain the high pressure seal 122 at a temperature of about 150° C. to 250° C. can be The flow of coolant within the cooling channel 124 is controlled by the controller 180 via feedback received from a temperature sensor 116 or a flow sensor (not shown).

[0018] The high pressure vessel 100 has a port 117 through the body 110 . Port 117 has a pipe 118 through port 117 , which is coupled to heater 119 . One end of the pipe 118 is connected to the processing region 115 . The other end of the pipe 118 bifurcates into an inlet conduit 157 and an outlet conduit 161 . The inlet conduit 157 is fluidly connected to the gas panel 150 via an isolation valve 155 . Inlet conduit 157 is coupled to heater 158 . The exhaust conduit 161 is fluidly connected to the condenser 160 through an isolation valve 165 . The exhaust conduit 161 is coupled to the heater 162 . Heaters 119 , 158 , and 162 provide a processing gas, such as an oxidizing medium, flowing through pipe 118 , inlet conduit 157 , and outlet conduit 161 to a condensing point of the processing gas to about 250° C. is configured to maintain each at a temperature of Heaters 119 , 158 and 162 are powered by a power source 145 .

[0019] The gas panel 150 is configured to provide a processing gas under pressure, such as an oxidizing medium, into the inlet conduit 157 for delivery through the pipe 118 into the processing region 115 . The oxidizing medium includes an amine additive. The pressure of the processing gas introduced into the processing region 115 is monitored by a pressure sensor 114 coupled to the body 110 . The condenser 160 is fluidly coupled to the cooling fluid and is configured to condense the gaseous product flowing through the exhaust conduit 161 after removal from the processing region 115 through the pipe 118 . Condenser 160 converts the gaseous products from the gaseous phase to the liquid phase. A pump 170 is fluidly connected to the condenser 160 and pumps out the liquefied products from the condenser 160 . The operation of the gas panel 150 , the condenser 160 , and the pump 170 is controlled by the controller 180 .

[0020] Isolation valves 155 and 165 are configured to allow only one fluid to flow through pipe 118 into processing region 115 at a time. When the isolation valve 155 is opened, the isolation valve 165 is closed such that the processing gas flowing through the inlet conduit 157 enters the processing region 115 and the flow of the processing gas into the condenser 160 . is prevented On the other hand, when the isolation valve 165 is opened, the isolation valve 155 is closed so that the gaseous product is removed from the processing region 115 and flows through the exhaust conduit 161 , the gas panel 150 . The flow of gaseous products into it is prevented.

[0021] One or more heaters 140a , 140b (collectively 140 ) are disposed on body 110 and are configured to heat processing region 115 within high pressure vessel 100 . In some implementations, the heaters 140 are disposed on the outer surface 112 of the body 110 as shown in FIG. 1 , although in other implementations, the heaters 140 are disposed on the inside of the body 110 . It may be disposed on the surface 113 . Each of the heaters 140 may be a resistive coil, a lamp, a ceramic heater, a graphite-based carbon fiber composite (CFC) heater, a stainless steel heater, or an aluminum heater. The heaters 140 are powered by a power source 145 . Power to the heaters 140 is controlled by the controller 180 via feedback received from the temperature sensor 116 . A temperature sensor 116 is coupled to the body 110 and monitors the temperature of the processing region 115 .

[0022] A cassette 130 coupled to an actuator (not shown) is moved into and out of the processing region 115 . Cassette 130 has a top surface 132 , a bottom surface 134 , and walls 136 . A wall 136 of the cassette 130 has a plurality of substrate storage slots 138 . Each substrate storage slot 138 is equally spaced along the wall 136 of the cassette 130 . Each substrate storage slot 138 is configured to hold a substrate 135 therein. Cassette 130 may have as many as 50 substrate storage slots 138 for holding substrates 135 . The cassette 130 provides an effective vehicle for processing the plurality of substrates 135 within the processing region 115 as well as for transferring the plurality of substrates 135 into and out of the high pressure vessel 100 .

[0023] The controller 180 controls the operation of the high pressure vessel 100 . The controller 180 controls the operation of the gas panel 150 , the condenser 160 , the pump 170 , the isolation valve 155 , and the isolation valve 165 , as well as the power source 145 . Controller 180 is also communicatively coupled to temperature sensor 116 , pressure sensor 114 , and cooling channel 124 . The controller 180 includes a central processing unit (CPU) 182 , a memory 184 , and support circuitry 186 . The CPU 182 may be any type of general-purpose computer processor that may be used in an industrial setting. Memory 184 may be random access memory, read-only memory, floppy, or hard disk drive, or other form of digital storage. Support circuitry 186 is typically coupled to CPU 182 and may include cache, clock circuits, input/output systems, power supplies, and the like.

[0024] The high-pressure vessel 100 provides a convenient chamber for performing a method of forming a silicon oxide film on a plurality of substrates 135 at a temperature of 550° C. or less. The heaters 140 are powered on to preheat the high pressure vessel 100 and maintain the processing region 115 at a temperature of about 550° C. or less. Simultaneously, heaters 119 , 158 , and 162 are powered on to preheat pipe 118 , inlet conduit 157 , and outlet conduit 161 , respectively.

[0025] A plurality of substrates 135 are loaded on the cassette 130 . The door 120 of the high pressure vessel 100 is opened to move the cassette 130 into the processing region 115 . The door 120 is then sealably closed to convert the high pressure vessel 100 into a high pressure vessel. The high pressure seal 122 ensures that there is no pressure leakage from the processing region 115 once the door 120 is closed.

[0026] A processing gas (ie, an oxidizing medium comprising an amine additive) is provided by a gas panel 150 into the processing region 115 inside the high pressure vessel 100 . Isolation valve 155 is turned on by controller 180 to allow processing gas to flow into processing region 115 through inlet conduit 157 and pipe 118 . The processing gas is introduced at a flow rate of, for example, about 500 seem to about 2000 seem. At this time, the isolation valve 165 is kept off. In some implementations, the pressure within the high pressure vessel 100 is gradually increased. The high pressure is effective, especially in the deeper portions of the trenches, for oxygen to be injected into the silicon-containing film to a more fully oxidized state.

[0027] In some implementations described herein, the processing gas is steam comprising the amine additive under a pressure of from about 1 bar to about 65 bar (eg, from about 35 bar to about 65 bar; or from about 40 bar to 60 bar). However, in other implementations, other oxidizing media such as, but not limited to, ozone, oxygen, peroxides, or hydroxide-containing compounds may be used with or in place of steam. The amine additive added to the oxidizing medium may be ammonium or ammonia. When sufficient steam has been released by the gas panel 150 , the isolation valve 155 is turned off by the controller 180 .

[0028] During processing of substrates 135 , inlet conduit 157 , outlet conduit 161 , and pipe 118 as well as processing region 115 are maintained at a temperature and pressure such that the processing gas remains in the gaseous phase. The temperatures of the processing region 115 as well as the inlet conduit 157 , the outlet conduit 161 , and the pipe 118 are at a temperature higher than the condensation point of the processing gas (eg, 100° C.) at the applied pressure, but no more than 550° C. is maintained as The processing region 115 as well as the inlet conduit 157 , the outlet conduit 161 , and the pipe 118 are maintained at a pressure lower than the condensing pressure of the processing gas at the applied temperature. Accordingly, the processing gas is selected. In the implementation described herein, steam under a pressure of about 1 bar to about 65 bar is an effective processing gas when the high pressure vessel is maintained at a temperature of about 100°C to about 550°C. This ensures that the steam does not condense into water harmful to the silicon film deposited on the substrate 135 .

[0029] When the film is observed to have the desired density, as verified by testing the film's wet etch rate and electrical leakage and dielectric breakdown properties, processing is complete. Isolation valve 165 is then opened to flow processing gas from processing region 115 through pipe 118 and exhaust conduit 161 into condenser 160 . The processing gas is condensed into the liquid phase in condenser 160 . The liquefied processing gas is then removed by pump 170 . When the liquefied processing gas is completely removed, the isolation valve 165 is closed. The heaters 140 , 119 , 158 , and 162 are then powered off. The door 120 of the high pressure vessel 100 is then opened to remove the cassette 130 from the processing region 115 .

[0030] 2A illustrates a semiconductor device 200 including a substrate 202 and a silicon-containing film 208 deposited thereon, in accordance with one or more implementations described herein. The substrate 202 may be used in place of each of the substrates 135 when loaded onto the cassette 130 as shown in FIG. 1 . One or more openings or vias 204 may be formed in the substrate 202 . Although only one via 204 is shown in the semiconductor device 200 , multiple vias 204 may be included. In such an embodiment, each via 204 of the plurality of vias may have the same dimensions, such as a depth of about 10 μm. Additionally, sides 214 and bottom 216 of vias 204 may be patterned and may not be planar as shown. A silicon-containing film 208 may be deposited on the vias 204 and each exposed surface of the substrate 202 (ie, the top surface 212 , the sides 214 , and the bottom 216 ). have. The silicon-containing film 208 may be deposited using atomic layer deposition (ALD). The silicon-containing film 208 may be made of silicon or silicon nitride.

[0031] Substrate 202 may include one or more materials used to form semiconductor devices, such as metal contacts, trench isolations, gates, bitlines, or any other interconnection features. The substrate 202 may include one or more metal layers, one or more dielectric materials, a semiconductor material, and combinations thereof, utilized to fabricate semiconductor devices. For example, the substrate 202 may include an oxide material, a nitride material, a polysilicon material, or the like, depending on the application. In one implementation targeted for memory applications, the substrate 202 may include a silicon substrate material, an oxide material, and a nitride material, with or without polysilicon interposed therebetween.

[0032] In another implementation, the substrate 202 may include a plurality of alternating oxide and nitride materials (ie, oxide-nitride-oxide (ONO)) (not shown) deposited on a surface of the substrate. In various implementations, the substrate 202 comprises a plurality of alternating oxide and nitride materials, one or more oxide or nitride materials, polysilicon or amorphous silicon materials, oxides alternating with amorphous silicon, alternating with polysilicon. oxides, undoped silicon alternating with doped silicon, undoped polysilicon alternating with doped polysilicon, or undoped amorphous silicon alternating with doped amorphous silicon. Substrate 202 may be any substrate or material surface on which film processing is performed. For example, the substrate 202 may be made of a material such as crystalline silicon, silicon oxide, silicon oxynitride, silicon nitride, strained silicon, silicon germanium, tungsten, titanium nitride, doped or undoped polysilicon, doped doped or undoped silicon wafers and patterned or unpatterned wafers, silicon on insulator (SOI), carbon doped silicon oxides, silicon nitrides, doped silicon, germanium, gallium arsenide, glass, sapphire, low k dielectrics, and combinations thereof.

[0033] 2B illustrates a semiconductor device 200 having a conformal silicon oxide film 206 formed in vias 204 , in accordance with one or more implementations described herein. The silicon oxide film 206 is formed on the substrate 202 and the silicon-comprising film 208 at a temperature of 550° C. or less, such as between about 350° C. and about 505° C. The silicon oxide film 206 is formed using high pressure annealing at a pressure of 1 bar or higher, such as about 35 bar to about 65 bar, in an oxidizing medium comprising an amine additive.

[0034] The oxidizing medium may include steam, oxygen, peroxide, and the like, and the amine additive may include ammonium (NH ₄ ) or ammonia (NH ₃ ). The oxidizing medium may include from about 1,000 ppm to about 20,000 ppm, such as about 7,000 ppm, of the amine additive. In one embodiment, _{steam with about 7,000 ppm NH 3} as the amine additive is used as the oxidizing medium. When reacting films comprising silicon nitride, a hydrogen-based additive may be added to the oxidizing medium. The hydrogen-based additive may be added in addition to or in place of the amine additive when reacting the silicon nitride comprising the films. The hydrogen-based additive may include pure hydrogen (H ₂ ) or a trace amount of hydrogen as a component of the inert gas. Amine and/or hydrogen-based additives added to the oxidizing medium can improve the oxidation rate by about 2 to 3 times compared to high temperature rapid thermal oxidation films. In one embodiment, the annealing process used to form the silicon oxide film 206 is performed at a pressure of about 40 bar to about 60 bar for about 1 hour.

[0035] The silicon-containing film 208 is disposed between the substrate 202 and the silicon oxide film 206 , but the silicon-containing film 208 may have a smaller thickness after formation of the silicon oxide film 206 . In one embodiment, the silicon-containing film 208 is completely oxidized (ie, the silicon oxide film 208 ) such that the silicon-containing film 208 is no longer disposed between the silicon oxide film 206 and the substrate 202 . 206 may be in contact with the substrate 202 ). Although not shown, the silicon oxide film 206 and/or the silicon-containing film 208 may be disposed on the surface 212 of the substrate 202 .

[0036] 2C illustrates an enlarged cross-sectional view of a top portion of semiconductor device 200 taken along line 2C-2C. The 2C-2C line may be about 500 nm below the surface 212 of the semiconductor device 200 . 2D illustrates an enlarged cross-sectional view of a lowermost portion of the semiconductor device 200 taken with a 2D-2D line. The 2D-2D line may be about 500 nm above the bottom 216 of the semiconductor device 200 . The silicon oxide film 206 in the uppermost portion of FIG. 2C has a thickness 210A, and the silicon oxide film 206 in the lowermost portion of FIG. 2D has a thickness 210B (collectively 210).

[0037] 2C and 2D , the thickness 210A of the uppermost portion of the silicon oxide film 206 is approximately equal to the thickness 210B of the lowermost portion of the silicon oxide film 206 . The silicon oxide film 206 has a substantially uniform thickness 210 at both the top and bottom portions of the via 204 , which is approximately 100% conformal to the silicon oxide layer 206 (ie, the top portion of the silicon oxide layer 206 ). the ratio of the thickness 210A to the thickness 210B of the lowermost portion). A silicon oxide film 206 formed using an oxidizing medium comprising an amine additive at a temperature of less than about 550° C. and a pressure of greater than 1 bar is about 90 for sides 214 and bottom 216 of via 204 . greater than % nearly uniform conformality. The silicon oxide film 206 has a uniform thickness 210 of from about 20 angstroms to about 400 angstroms, such as from about 150 angstroms to about 400 angstroms.

[0038] 3 depicts a process flow diagram of a method 300 for forming a silicon oxide film on a substrate in accordance with one or more implementations described herein. The substrate may be a substrate 135 as depicted in FIG. 1 or a substrate 202 as depicted in FIGS. 2A-2D . For clarity, the method 300 will be described with reference to elements of the semiconductor device 200 of FIGS. 2A-2D .

[0039] The method 300 begins at operation 310 by loading a substrate 202 having a silicon-containing film 208 deposited thereon (as shown in FIG. 2A ) into a high pressure vessel. The high pressure vessel may be the high pressure vessel 100 depicted in FIG. 1 . The substrate 202 may be positioned in a cassette, such as a cassette 130 as shown in FIG. 1 . Prior to loading the substrate 202 into the high pressure vessel, a silicon-containing film 208 is deposited on the vias 204 and each exposed side or surface 212 , 214 , 216 of the substrate 202 . The silicon-containing film 208 may be deposited using ALD. The silicon-containing film 208 may be made of silicon or silicon nitride. The substrate 202 may be comprised of any of the materials discussed in FIGS. 2A-2D above.

[0040] In one implementation, the surface 212 of the substrate 202 includes a surface formed therein with patterned structures, such as trenches, holes, or vias 204, as shown in FIGS. 2A-2D . . In such an embodiment, the silicon-containing film 208 is disposed on the sides 214 and the bottom 216 of the vias 204 . Alternatively, the surface 212 of the substrate 202 may be substantially planar. The substrate 202 may also have a substantially planar surface 212 , wherein the structure is formed to a desired elevation on or within the substantially planar surface 212 . The surface 212 of the substrate 202 may include trenches, holes, vias, or elevations, although the patterns of the surface 212 will be referred to throughout as vias and are referred to as “vias”. The term is not intended to be limiting.

[0041] In operation 320 , the substrate 202 is exposed to such an oxidizing medium comprising an amine additive at a target temperature of from the condensation point of the oxidizing medium (eg, about 100° C.) to about 550° C. and a pressure of greater than 1 bar. In one implementation, the target temperature is from about 100°C to about 550°C (eg, from about 350°C to about 520°C; or from about 400°C to about 505°C). The temperature may be ramped to a target temperature using heaters 140a and 140b. In addition to ramping the temperature, the pressure may be ramped to a target pressure. In one embodiment, the pressure is from about 1 bar to about 65 bar (eg, from about 30 bar to about 65 bar; or from about 40 bar to about 60 bar).

[0042] In one embodiment, the oxidizing medium comprises steam, ozone, oxygen, water vapor, heavy water, peroxides, hydroxide-containing compounds, oxygen isotopes (14, 15, 16, 17, 18, etc.) and hydrogen isotopes ( 1, 2, 3), or combinations thereof. The peroxide may be gaseous hydrogen peroxide. In some implementations, the oxidizing medium includes hydroxide ions, such as, but not limited to, water vapor or heavy water in vapor form. The amine additive may consist of ammonium or ammonia. The oxidizing medium may include from about 1,000 ppm to about 20,000 ppm, such as about 7,000 ppm, of the amine additive. In one embodiment, _{steam with about 7,000 ppm NH 3} as the amine additive is used as the oxidizing medium. When reacting films comprising silicon nitride, a hydrogen-based additive may be added to the oxidizing medium. The hydrogen-based additive may be added in addition to or in place of the amine additive when reacting the silicon nitride comprising the films. The hydrogen-based additive may include pure hydrogen (H ₂ ) or a trace amount of hydrogen as a component of the inert gas. Amine and/or hydrogen-based additives added to the oxidizing medium can improve the oxidation rate by about 2 to 3 times compared to high temperature rapid thermal oxidation films.

[0043] In some implementations, the substrate 202 or the plurality of substrates are exposed to steam comprising an amine additive at a pressure of about 5 bar to about 60 bar, wherein the pressure can be gradually increased from 5 bar to about 60 bar. . In some implementations, the steam comprising the amine additive is introduced into the high pressure vessel at a flow rate of, for example, from about 500 sccm to about 5,000 sccm (e.g., from about 500 sccm to about 5,000 sccm; or from about 500 sccm to about 2,000 sccm). In one embodiment, water vapor comprising the amine additive is injected into the high pressure vessel, and the water vapor forms steam comprising the amine additive when heated in the high pressure vessel. In another embodiment, water or water vapor comprising the amine additive is present in the high pressure vessel before being heated to the target temperature. Water or water vapor present in the high pressure vessel forms steam containing the amine additive when the high pressure vessel is heated to a target temperature.

[0044] In operation 330 , a silicon oxide film 206 is formed on the substrate 202 . The silicon oxide film 206 is formed as a conformal or uniform layer. A silicon oxide film 206 is uniformly formed on the sides 214 and bottom 216 of the vias 204 and on the surface 212 of the substrate 202 . The silicon oxide film 206 may be deposited with greater than about 90% conformality on the sides 214 and the bottom 216 of the via 204 , as shown in FIGS. 2A-2D . The silicon oxide film 206 may have a thickness 210 of from about 20 angstroms to about 400 angstroms, such as from about 150 angstroms to about 400 angstroms.

[0045] In operation 330 , when the substrate 202 having the silicon-containing film 208 is exposed to an oxidizing medium comprising an amine additive to form the silicon oxide film 206 , the high pressure vessel moves from the condensation point of the oxidizing medium to the high pressure vessel. maintained at a temperature of about 550°C. In one embodiment in which steam comprising the amine additive is used at a pressure of about 40 bar to about 60 bar, the temperature of the high pressure vessel is maintained at about 400°C to about 505°C. In some implementations, forming the silicon oxide film 206 on the substrate 202 of operation 330 is performed for a time-period of about 5 minutes to about 150 minutes, such as about 30 minutes to about 120 minutes. . In at least one implementation, utilizing an oxidizing medium comprising an amine additive at a temperature of about 400° C. to about 505° C. and a pressure of about 60 bar for about 120 minutes causes the silicon-containing film 208 to no longer form the substrate 202 . ) and the silicon-containing film 208 is completely oxidized so as not to be disposed between the silicon oxide layer 206 .

[0046] Under high pressure, application of an oxidizing medium containing an amine additive, such as steam containing ammonia, causes a high concentration of oxidized species from the oxidizing medium to penetrate deeply into the silicon-containing film, resulting in more silicon oxide film material through oxidation of the oxidized species. make it possible to create Without wishing to be bound by theory, it is believed that the high pressure inside the high pressure vessel induces diffusion of oxidizing species into deeper vias. Moreover, it is believed that the presence of the amine additive in the steam allows the target pressure to be achieved at a much faster rate and increases the oxidation rate by a factor of 2-3 compared to high temperature rapid thermal oxidation films.

[0047] The quality of the silicon oxide film 206 depends on the wet etch rate of the silicon oxide film 206 formed using an oxidizing medium comprising an amine additive at a temperature of less than 550° C. and a pressure of greater than 1 bar, without utilizing the amine additive. It can be verified by comparing the wet etch rate of a silicon oxide film (ie, high temperature rapid thermal oxidation films) formed at temperatures exceeding 800°C at low pressures. When performing wet etching on both the silicon oxide film 206 having a thickness greater than about 20 angstroms and the high temperature rapid thermal oxidation film having the same thickness, the wet etching rate is almost the same for both films. In one embodiment, both the silicon oxide film 206 and the high temperature rapid thermal oxidation film had a wet etch rate of about 26 angstroms/min to about 32 angstroms/min.

[0048] Additionally, by comparing the leakage and capacitive equivalent thickness of a silicon oxide film 206 formed using an oxidizing medium comprising an amine additive at a temperature of less than 550° C. and a pressure of greater than 1 bar with a high temperature rapid thermal oxidation film, silicon oxide The quality of the film 206 may be further verified. When comparing leakage of a silicon oxide film 206 having a thickness greater than about 20 angstroms with leakage of a high temperature rapid thermal oxide film having the same thickness, both silicon oxide films show a thermal trend line or voltage leakage versus thickness graph. The extrapolated columns of were placed along the trendline. Accordingly, the leakage and capacitive equivalent thickness of the silicon oxide film 206 is approximately equal to or comparable to that of the high temperature rapid thermal oxidation film. In one embodiment, both the silicon oxide film 206 and the high temperature rapid thermal oxidation film had a leakage to capacitive equivalent thickness of about 0.22 V/angstrom to about 0.25 V/angstrom.

[0049] Thus, for a process performed at a relatively low temperature of 550° C. or lower, the achievement of film quality improvement is substantially similar to a process performed at 800° C. or higher at a lower pressure. The process performed at a relatively low temperature of 550° C. or less utilizing an oxidizing medium containing an amine additive allows the silicon oxide layer to be deposited uniformly, including depositions on substrates having a difficult or uneven structure.

[0050] Moreover, the formation of silicon oxide films using an oxidizing medium containing amine and/or hydrogen-based additives at a temperature of less than 550° C. and a pressure of greater than 1 bar is difficult for the silicon oxide film to undergo high temperature rapid thermal oxidation while maintaining high quality. It makes it possible to achieve thicknesses greater than the capabilities of the process. Thus, to deposit a silicon oxide film, utilizing an oxidizing medium comprising an amine additive at a temperature of less than 550° C. and a pressure of greater than 1 bar is conformal with the same quality and increased oxidation rate as a high temperature rapid thermal oxidation film. resulting in a thick or uniform silicon oxide film.

[0051] Moreover, to deposit a silicon oxide film, utilizing an oxidizing medium comprising an amine additive at a temperature less than about 550 °C expands the process window for forming silicon oxide films, since the process window is no longer about 800 °C. This is because it is not limited to the above temperatures. Extending the process window increases the capabilities of current tools used to form silicon oxide films, reducing overall resources to a lesser extent.

[0052] While the foregoing relates to embodiments of the present disclosure, other and additional embodiments of the disclosure may be devised without departing from the basic scope of the disclosure, the scope of which is set forth in the following claims. is determined by

Claims (15)

A method of forming a silicon oxide film, comprising:
loading a substrate having a silicon-containing film deposited thereon into a processing region of a high-pressure vessel; and
forming a silicon oxide film on the silicon-containing film;
The step of forming a silicon oxide film on the silicon-containing film,
exposing the silicon-containing film to an oxidative medium comprising an amine additive at a pressure greater than about 1 bar; and
maintaining the high pressure vessel at a temperature between about 100°C and about 550°C;
A method of forming a silicon oxide film. According to claim 1,
wherein the amine additive comprises ammonium or ammonia, and the oxidizing medium comprises from about 1,000 ppm to about 20,000 ppm of the amine additive.
A method of forming a silicon oxide film. According to claim 1,
wherein the oxidizing medium is selected from the group consisting of steam, peroxides, oxygen, ozone, water vapor, heavy water, hydroxide-containing compounds, oxygen isotopes, hydrogen isotopes, and combinations thereof;
A method of forming a silicon oxide film. According to claim 1,
wherein the silicon-containing film is a silicon nitride film, and the oxidizing medium further comprises a hydrogen-based additive.
A method of forming a silicon oxide film. According to claim 1,
wherein the silicon oxide film has a uniform thickness of from about 20 angstroms to about 400 angstroms, and the temperature is from about 400 °C to about 505 °C;
A method of forming a silicon oxide film. According to claim 1,
wherein the step of forming a silicon oxide film on the silicon-containing film is performed for a time-period of about 5 minutes to about 150 minutes.
A method of forming a silicon oxide film. A method of forming a conformal silicon oxide film comprising:
depositing a silicon-containing film on a substrate comprising a plurality of vias, wherein the silicon-containing film is deposited on the plurality of vias and each exposed surface of the substrate;
loading the substrate on which the silicon-containing film is deposited into a processing region of a high pressure vessel; and
forming a conformal silicon oxide film on the silicon-containing film;
Forming a conformal silicon oxide film on the silicon-containing film comprises:
exposing the silicon-containing film to an oxidizing medium comprising an amine additive, wherein the oxidizing medium comprises from about 1,000 ppm to about 20,000 ppm of the amine additive; and
maintaining the high pressure vessel at a temperature of about 100° C. to about 550° C. and a pressure of about 1 bar to about 65 bar;
A method of forming a conformal silicon oxide film. 8. The method of claim 7,
wherein the amine additive comprises ammonium or ammonia, and the oxidizing medium comprises about 7,000 ppm of the amine additive.
A method of forming a conformal silicon oxide film. 8. The method of claim 7,
wherein the oxidizing medium is selected from the group consisting of steam, peroxide, oxygen, ozone, water vapor, heavy water, hydroxide-containing compounds, oxygen isotopes, hydrogen isotopes, and combinations thereof, and wherein the silicon-containing film comprises: containing silicon or silicon nitride;
A method of forming a conformal silicon oxide film. 8. The method of claim 7,
wherein the oxidizing medium is steam, the amine additive is ammonia, the silicon-containing film is a silicon nitride film, and the oxidizing medium further comprises a hydrogen-based additive.
A method of forming a conformal silicon oxide film. 8. The method of claim 7,
The step of forming a silicon oxide film on the silicon-containing film is performed at a temperature of about 400° C. to about 505° C. for a time-period of about 5 minutes to about 150 minutes, and the conformal silicon oxide film is formed from about 20 angstroms to about 20 angstroms. having a uniform thickness of about 400 angstroms;
A method of forming a conformal silicon oxide film. A method of forming a silicon oxide film, comprising:
loading a substrate having a silicon-containing film deposited thereon into a processing region of a high-pressure vessel; and
forming a silicon oxide film on the silicon-containing film;
The step of forming a silicon oxide film on the silicon-containing film,
exposing the silicon-containing film to an oxidizing medium comprising ammonia, wherein the oxidizing medium is selected from the group of steam, oxygen, and peroxide; and
maintaining the high pressure vessel at a temperature of from about 400° C. to about 505° C. and a pressure greater than about 10 bar;
wherein the silicon oxide film has a uniform thickness of about 100 angstroms to about 400 angstroms;
A method of forming a silicon oxide film. 13. The method of claim 12,
wherein the oxidizing medium comprises from about 1,000 ppm to about 20,000 ppm of the ammonia;
A method of forming a silicon oxide film. 13. The method of claim 12,
wherein the silicon-containing film comprises silicon or silicon nitride, and the pressure is from about 10 bar to about 60 bar;
A method of forming a silicon oxide film. 13. The method of claim 12,
wherein the step of forming a silicon oxide film on the silicon-containing film is performed for a time-period of about 5 minutes to about 120 minutes.
A method of forming a silicon oxide film.

Images