Semiconductor structure, method of manufacturing a semiconductor structure and device

Abstract

The application provides a semiconductor structure, a preparation method and device of the semiconductor structure, relates to the technical field of semiconductors, and aims to solve the technical problem of high preparation cost of the semiconductor structure. The preparation method comprises the following steps: providing a substrate, wherein a groove is formed in the substrate; providing a silicon-oxygen polymer solution on the surface of the substrate, and forming a silicon-oxygen polymer layer by spin coating the silicon-oxygen polymer solution through a spin-on dielectric process, wherein the silicon-oxygen polymer solution contains a doping element, and the doping element comprises boron and phosphorus; and performing heat treatment on the silicon-oxygen polymer layer, wherein the temperature threshold of the heat treatment is 120-150 DEG C. The silicon-oxygen polymer layer is irradiated with ultrasonic waves for a preset time length, so as to form a porous silicon layer containing silicon hydroxide bonds; and an oxidizing gas is provided to the porous silicon layer, the oxidizing gas reacts with the silicon hydroxide bonds in the porous silicon layer, so as to form a borophosphosilicate glass film; and the borophosphosilicate glass film fills the groove. The application can reduce the preparation cost of the semiconductor structure.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and in particular to a semiconductor structure, a method for preparing the semiconductor structure, and an apparatus. Background Technology

[0002] As the integration level of semiconductor integrated circuits continues to increase and the critical dimensions of semiconductor manufacturing processes continue to shrink, the difficulty in preparing the interlayer insulating film used to isolate adjacent conductors is also constantly increasing.

[0003] In related technologies, a chemical vapor deposition (SACVD) process at sub-atmospheric pressure is typically used to prepare borosilicate glass films, for example. During the preparation of borosilicate glass films, the precursor liquid needs to be vaporized using a vaporization device, and then it needs to be heated at a high temperature (e.g., 480°C) to give the borosilicate glass film good thermal fluidity, thereby enabling the borosilicate glass film to better fill the trenches.

[0004] However, high-temperature processes pose a significant challenge to the heat resistance of the preparation equipment, leading to high preparation costs. Summary of the Invention

[0005] In view of the above problems, this application provides a semiconductor structure, a method for preparing the semiconductor structure, and an apparatus. During the preparation process, the borosilicate glass film can be formed by means of ultrasonic-assisted oxidation, without the need for a vaporization device and high-temperature heating. This can reduce the process temperature of the semiconductor structure, thereby reducing the preparation cost of the semiconductor structure and improving the quality and reliability of the borosilicate glass film.

[0006] To achieve the above objectives, the embodiments of this application provide the following technical solutions:

[0007] The first aspect of this application provides a method for fabricating a semiconductor structure, including:

[0008] A substrate is provided in which trenches are formed;

[0009] A silicon oxide polymer solution is provided to the surface of the substrate, and a spin-coating dielectric process is used to spin-coat the silicon oxide polymer solution to form a silicon oxide polymer layer. The silicon oxide polymer solution contains doping elements, including boron and phosphorus.

[0010] The silicon-oxygen polymer layer is subjected to heat treatment, wherein the temperature threshold for the heat treatment is 120°C to 150°C.

[0011] The silicon-oxygen polymer layer is irradiated with ultrasound for a predetermined duration to form a porous silicon layer containing silicon hydroxide bonds;

[0012] An oxidizing gas is provided to the porous silicon layer, and the oxidizing gas reacts with the silicon hydroxide bonds in the porous silicon layer to form a borosilicate glass film; wherein the borosilicate glass film fills the trench.

[0013] In some alternative embodiments, the temperature threshold for heat treatment of the silicon-oxygen polymer layer is 130°C.

[0014] In some alternative embodiments, the silicone polymer solution includes polysiloxane, triethylboron, triethyl phosphate, and a solvent.

[0015] In some alternative embodiments, the concentration of the polysiloxane is 5% to 20%.

[0016] In some alternative embodiments, the oxidizing gas includes at least one of ozone, oxygen, oxygen nitride, dioxygen nitride, nitrogen dioxide, and carbon oxide.

[0017] In some alternative embodiments, the oxidizing gas includes ozone.

[0018] In some alternative embodiments, the concentration of ozone is 5% to 15%.

[0019] In some optional embodiments, the spin coating speed in the spin coating dielectric process is 500 r / min to 1500 r / min.

[0020] In some alternative embodiments, the frequency of the ultrasonic wave is 40kHz to 60kHz; and / or, the power of the ultrasonic wave is 500W to 600W.

[0021] In some alternative embodiments, the duration of irradiation of the silicone polymer layer with the ultrasonic waves is less than or equal to 3 minutes.

[0022] A second aspect of this application provides a semiconductor structure, fabricated using the semiconductor structure fabrication method described in the above embodiments, comprising:

[0023] Substrate, the substrate having trenches;

[0024] A borosilicate glass film is used to fill the trench.

[0025] A third aspect of this application provides a semiconductor structure fabrication apparatus, comprising:

[0026] A first chamber is provided with a spin-coating dielectric device and a heating stage. The spin-coating dielectric device includes a spin-coating stage and a spin-coating head. The spin-coating head is located above the spin-coating stage and can rotate relative to the spin-coating stage about the vertical axis of the spin-coating stage. The spin-coating stage is configured to support a substrate, and the spin-coating head is configured to spin-coat a silicone polymer solution on the surface of the substrate. The heating stage is configured to heat the substrate on the spin-coating stage.

[0027] A second chamber is provided in which a support platform and an ultrasonic device are located above the support platform. The support platform is configured to support the substrate, and the ultrasonic device is configured to irradiate ultrasonic waves onto the substrate.

[0028] A gas passage, connected to the second chamber, is configured to supply oxidizing gas to the second chamber.

[0029] In some alternative embodiments, a conveying device is also included, disposed between the first chamber and the second chamber, the conveying device being configured to convey the substrate in the first chamber to the second chamber.

[0030] In some alternative embodiments, a vacuum device is also included, wherein the second chamber has an exhaust passage, and the vacuum device is configured to extract byproduct gases generated in the second chamber through the exhaust passage.

[0031] In some alternative embodiments, the heating unit and the spin coating unit are an integral structure, and the heating unit is configured to be electrically connected to a power source.

[0032] In the semiconductor structure, semiconductor structure fabrication method, and apparatus provided in this application embodiment, a silicon oxide polymer layer is formed by spin-coating a silicon oxide polymer solution on the substrate surface using a spin-coating dielectric process. The silicon oxide polymer layer is then heat-treated, with a temperature threshold of 120°C to 150°C to evaporate the solvent in the silicon oxide polymer solution. Subsequently, the heat-treated silicon oxide polymer layer is irradiated with ultrasound for a preset duration to form a porous silicon layer containing silicon hydroxide bonds. An oxidizing gas is provided to the porous silicon layer, and the oxidizing gas reacts with the hydroxide bonds in the porous silicon layer to form a borosilicate glass film. The borosilicate glass film fills the trenches. In this way, the formation of the borosilicate glass film can be achieved by using an ultrasound-assisted oxidation method without the need for a vaporization device and high-temperature heating. This reduces the process temperature of the semiconductor structure, thereby reducing the fabrication cost of the semiconductor structure and improving the quality and reliability of the borosilicate glass film.

[0033] In addition to the technical problems solved by the embodiments of this application, the technical features constituting the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions described above, other technical problems that can be solved by the semiconductor structure, the method and apparatus for preparing the semiconductor structure provided by the embodiments of this application, other technical features included in the technical solutions, and the beneficial effects brought about by these technical features will be further explained in detail in the specific embodiments. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 A schematic flowchart illustrating a method for fabricating a semiconductor structure according to an embodiment of this application;

[0036] Figure 2 A schematic cross-sectional view of a substrate for a semiconductor structure provided in an embodiment of this application;

[0037] Figure 3 A schematic cross-sectional view of a boron phosphosilicate glass film formed on a substrate of a semiconductor structure provided in an embodiment of this application;

[0038] Figure 4 A schematic diagram illustrating the formation process of a boron phosphosilicate glass film in a semiconductor structure provided in an embodiment of this application;

[0039] Figure 5 A schematic diagram of a semiconductor structure fabrication apparatus provided in an embodiment of this application;

[0040] Figure 6 This is a partial structural schematic diagram of another structure of the semiconductor structure fabrication apparatus provided in one embodiment of this application.

[0041] Figure label:

[0042] 100 - Semiconductor structure; 110 - Substrate; 111 - Trench; 120 - Silicon-oxygen polymer solution;

[0043] 130-Silica polymer layer; 140-Borophosphosilicate glass film;

[0044] 200 - Preparation apparatus; 210 - Spin coating dielectric apparatus; 211 - Spin coating machine stand; 212 - Spin coating head;

[0045] 220 - Heating platform; 230 - Support platform; 240 - Ultrasonic device; 241 - Ultrasonic wave;

[0046] 250 - Gas passage; 260 - Exhaust passage. Detailed Implementation

[0047] The inventors of this application discovered in their practical work that as the integration density of integrated circuit chips continues to increase and the critical dimensions of semiconductor processes continue to shrink, the aspect ratio of trenches in semiconductor structures is also continuously increasing. In related technologies, when using sub-atmospheric chemical vapor deposition (SACVD) to deposit dielectric thin film layers such as borosilicate glass films in trenches, it is first necessary to use a vaporization device to vaporize the precursor (e.g., a silicon-oxygen polymer solution). The vaporization efficiency of the vaporization device directly affects the quality of the formed borosilicate glass. In addition, the temperature in the SACVD process is relatively high (e.g., 480°C), which poses a great challenge to the heat resistance of the semiconductor structure fabrication equipment, resulting in high semiconductor structure fabrication costs and unstable reliability of the prepared borosilicate glass films.

[0048] To address the aforementioned issues, this application provides a semiconductor structure, a method for fabricating the semiconductor structure, and an apparatus for doing so. A silicon-oxygen polymer layer is formed by spin-coating a silicon-oxygen polymer solution onto a substrate surface using a spin-coating dielectric process. The silicon-oxygen polymer layer is then heat-treated at a temperature threshold of 120°C to 150°C to evaporate the solvent in the silicon-oxygen polymer solution. Subsequently, the heat-treated silicon-oxygen polymer layer is irradiated with ultrasound for a predetermined duration to form a porous silicon layer containing silicon hydroxide bonds. An oxidizing gas is then supplied to the porous silicon layer, reacting with the hydroxide bonds to form a borosilicate glass film. This borosilicate glass film fills the trenches. Thus, the formation of the borosilicate glass film can be achieved using ultrasound-assisted oxidation, eliminating the need for a vaporization device and high-temperature heating. This reduces the process temperature of the semiconductor structure, thereby lowering the fabrication cost and improving the quality and reliability of the borosilicate glass film.

[0049] To make the above-mentioned objectives, features, and advantages of the embodiments of this application more apparent and understandable, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0050] In a first aspect, embodiments of this application provide a method for preparing a semiconductor structure. This method is mainly used to prepare a semiconductor structure, which includes a substrate and a borosilicate glass film located on the substrate. The borosilicate glass film can be prepared by the above-described preparation method.

[0051] Figure 3 This is a cross-sectional schematic diagram of a substrate with a semiconductor structure provided in this application, in which the trenches are filled with a boron phosphosilicate glass film. Please refer to... Figure 3 As shown, the semiconductor structure 100 can be a substrate 110, in which trenches 111 are formed. A borosilicate glass film 140, for example, can be formed within the trenches 111 and on the surface of the substrate 110. The borosilicate glass film 140 can electrically isolate multiple metal lines disposed in the substrate 110 to avoid signal interference between adjacent metal lines, thereby improving the transmission stability of electrical signals in the semiconductor structure 100 and thus improving the stability of the semiconductor structure 100. Other insulating materials, such as silicon dioxide, can also be filled into the trenches 111, and all can be prepared using the above-described method.

[0052] The following section will take the formation of boron phosphosilicate glass films in trenches and on the substrate surface as an example to describe the preparation method in detail.

[0053] Figure 1 This is a schematic flowchart illustrating a method for fabricating a semiconductor structure according to an embodiment of this application. Please refer to... Figure 1 As shown, the method for fabricating the semiconductor structure provided in this application includes:

[0054] Step S101: Provide a substrate in which trenches are formed.

[0055] Combination Figure 2 As shown, substrate 110 can provide a structural basis for subsequent structures and processes. The material of substrate 110 may include any or more of silicon, germanium, silicon-germanium, silicon carbide, silicon-on-insulator substrate, and germanium-on-insulator substrate. In the embodiments of this application, at least a portion of substrate 110 is a silicon substrate, and the silicon material may be single-crystal silicon. Substrate 110 can be prepared by chemical vapor deposition (CVD) process.

[0056] A trench 111 is formed on the surface of the substrate 110. The cross-sectional shape of the trench 111 can be any shape such as circular, rectangular, square, or elliptical. The specific design can be adapted according to the requirements and is not limited here.

[0057] Specifically, a patterned photoresist layer can be formed on the substrate 110. Using the photoresist layer as a mask, one or more spaced trenches 111 can be etched on the substrate 110, such as... Figure 2 As shown in the image.

[0058] Step S102: Provide a silicon-oxygen polymer solution to the surface of the substrate, and spin-coat the silicon-oxygen polymer solution to form a silicon-oxygen polymer layer using a spin-coating dielectric process. The silicon-oxygen polymer solution contains doping elements, including boron and phosphorus.

[0059] Among them, the spin-on-dielectric (SOD) process, as a spin coating process, can be used to prepare high aspect ratio structures, and the process conditions are mild, with good gap filling performance.

[0060] Specifically, in combination Figure 5 As shown, a precursor can first be provided to the surface of the substrate 110. The precursor can be, for example, a silicone polymer solution 120. The silicone polymer solution 120 is then spin-coated onto the surface of the substrate 110 using a spin coater head 212 of a spin coater, so that the silicone polymer solution 120 fills the trenches 111 on the substrate 110 to form a planarized silicone polymer layer 130.

[0061] In some embodiments, the silicone polymer solution 120 may be made from, for example, silicone oil, and doped with triethylborane (TEB), triethyl phosphate (TEPO), and solvents. Triethylborane can provide boron as a dopant element to the silicone polymer solution 120, while triethyl phosphate can provide phosphorus as a dopant element to the silicone polymer solution 120. The solvent has a catalytic effect and can promote the formation of chemical bonds in the silicone polymer solution 120.

[0062] The solvent can be a compound containing hydroxyl or amino groups, such as H2O, C2H5OH, HCOOH, CH3COOH, C2H5NH2, etc.; the solvent can also be a sulfur-containing organic compound, such as C2H6OS, etc.

[0063] In some embodiments, the silicone polymer may also be other high molecular polymers containing silicon oxygen, including but not limited to polysiloxanes.

[0064] In some embodiments, the concentration of polysiloxane can be 5% to 20%.

[0065] For example, the concentration of polysiloxane can be 5%, 10%, 15%, 20%, etc., and can be adapted to actual needs without specific limitations.

[0066] In addition, the flow rates of triethylboron and triethyl phosphate in the silicon-oxygen polymer solution 120 can be determined based on the doping concentrations of boron and phosphorus. The specific doping concentrations of boron and phosphorus can also be adaptively designed according to actual needs, without any restrictions.

[0067] In the above scheme, a silicon oxide polymer solution 120 containing solvent and dopant elements is spin-coated into the trench 111 on the substrate 110 by a spin-coating dielectric (SOD) process until the trench 111 is filled to form a planarized silicon oxide polymer layer 130. It is not necessary to vaporize the silicon oxide polymer solution 120 through a vaporization device before depositing and filling the trench 111. In this way, the quality of the borophosphosilicate glass film 140 formed later will not be affected by the low vaporization efficiency, thereby improving the quality reliability of the borophosphosilicate glass film 140 formed later.

[0068] Step S103: Heat-treat the silicon-oxygen polymer layer, wherein the temperature threshold for heat treatment is 120℃~150℃.

[0069] Please continue to refer to Figure 5 As shown, after the silicon oxide polymer solution 120 is spin-coated to form a silicon oxide polymer layer 130 by spin-coating dielectric process, the silicon oxide polymer layer 130 can be baked by heat treatment process such as baking. The temperature threshold of heat treatment can be between 120°C and 150°C, so that the solvent evaporates from the surface of the silicon oxide polymer layer 130 as the temperature rises, and the solvent in the silicon oxide polymer layer 130 is removed.

[0070] In some embodiments, the heat treatment temperature of the silicone polymer layer 130 can be, for example, 120°C, 130°C, 135°C, 140°C, 145°C, and 150°C, etc., and can be set as needed, without being specifically limited here.

[0071] In this embodiment, the heat treatment temperature of the silicon-oxygen polymer layer 130 is relatively low. Therefore, the heat resistance of the semiconductor structure fabrication apparatus 200 is not required to be high due to the high heat treatment temperature, thereby reducing the fabrication cost.

[0072] Step S104: Irradiate the silicon-oxygen polymer layer with ultrasound for a preset duration to form a porous silicon layer containing hydrogen hydroxide bonds.

[0073] Please continue to refer to Figure 5 As shown in this embodiment, the heat-treated silicon-oxygen polymer layer 130 is irradiated with high-frequency ultrasonic waves 241 for a preset time to disrupt the bonding of silicon ions (SI-) and carbon ions (C-) in the silicon-oxygen polymer layer 130, thereby promoting the formation of silicon hydroxide bonds (SIOH-), so that the silicon hydroxide bonds (SIOH-) can react with oxidizing gases in subsequent processes to form a borosilicate glass film 140.

[0074] The frequency and power of the ultrasonic 241 can be adjusted according to requirements, and no specific restrictions are imposed here.

[0075] Step S105: An oxidizing gas is provided to the porous silicon layer, and the oxidizing gas reacts with the silicon hydroxide chemical bonds in the porous silicon layer to form a borosilicate glass film; wherein the borosilicate glass film fills the trench.

[0076] In some embodiments, the oxidizing gas includes, but is not limited to, at least one of ozone (O3), oxygen (O2), oxygen nitride (ON), dioxygen nitride (O2N), and carbon oxide (CO).

[0077] For example, in combination Figure 4 and Figure 5 As shown, the oxidizing gas is ozone (O3), and the raw material for the silicon oxide polymer solution 120 is polysiloxane, which is doped with triethylborane and triethyl phosphate. When the silicon oxide polymer solution 120 is spin-coated to form a silicon oxide polymer layer 130 using a spin-coating dielectric process, the silicon oxide polymer layer 130 is then baked and irradiated with ultrasound 241 for a preset duration. Finally, ozone is introduced into the cavity corresponding to the silicon oxide polymer layer 130, causing the silicon hydroxide bonds to react with the ozone to form a borosilicate glass film 140. The formed borosilicate glass film 140 fills the trenches 111 in the substrate 110 (e.g., ...). Figure 3 (as shown in the image); where the above chemical reaction formula is as follows:

[0078] -(SiCH3O)n- + TEB+TEPO+ O3=nSiO2+ CO2+ H2O (1)

[0079] Wherein, -(SiCH3O)n- is a silicon-oxygen polymer, and nSiO2 is a boron-phosphorus-silicon glass film 140 formed doped with phosphorus and boron elements.

[0080] In the above scheme, polysiloxane is used as raw material, and triethylboron (TEB) and triethyl phosphate (TEPO) are used to provide doped boron and phosphorus elements. After spin-coating the silicon oxide polymer solution 120 to form a silicon oxide polymer layer 130 by a spin-coating dielectric process, the silicon oxide polymer layer 130 is baked at a temperature of 120°C to 150°C to remove the solvent in the silicon oxide polymer layer 130. Then, it is irradiated with ultrasound 241 to break the SI-C bond and form silicon hydroxide bond (SIOH-). Ozone is then introduced to react with the silicon hydroxide bond (SIOH-) to form borosilicate glass film 140. It can be seen that in the embodiments of this application, the borosilicate glass film 140 can be formed by using ultrasound 241-assisted oxidation. There is no need to use a vaporization device to vaporize the silicon oxide polymer solution 120, nor is high temperature (e.g., 480°C) heating required. This can reduce the process temperature of semiconductor structure 100, thereby reducing the manufacturing cost of semiconductor structure 100 and improving the quality and reliability of borosilicate glass film 140.

[0081] In some embodiments, the conversion efficiency of the borosilicate glass membrane 140 can be controlled by adjusting the power of the ultrasonic wave 241 and the concentration of the oxidizing gas (e.g., ozone).

[0082] For example, the concentration of ozone can be 5% to 15%, such as 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, etc., which can be adaptively adjusted according to needs.

[0083] It should be noted that the concentration of ozone should not be too high or too low. Too high or too low concentrations will affect the uniformity of the borophosphosilicate glass film 140 during its formation, and poor uniformity will easily lead to the failure of the borophosphosilicate glass film 140.

[0084] In some embodiments, the power of the ultrasonic wave 241 can be 500W to 600W. For example, the power of the ultrasonic wave 241 can be 500W, 550W, 600W, etc., and can be adaptively adjusted according to the needs.

[0085] In addition, the frequency of ultrasound 241 can be 40kHz to 60kHz, for example, the frequency of ultrasound 241 is 40kHz, 45kHz, 50kHz, 55kHz, 60kHz, etc.

[0086] In some embodiments, the preset duration for irradiating the silicon-oxygen polymer layer 130 with ultrasonic waves 241 can be less than or equal to 3 minutes, and can be adjusted according to the thickness of the boron-phosphorus-silicon thin film.

[0087] In some embodiments, the thickness of the boron phosphosilicate film can also be adjusted to control the spin coating speed in the spin coating dielectric process. For example, the spin coating speed can be 500 r / min to 1500 r / min, such as 500 r / min, 600 r / min, 1000 r / min, 1200 r / min and 1500 r / min, etc., which can be specifically adjusted according to the thickness of the boron phosphosilicate film.

[0088] It should be noted that if the spin coating speed is too fast, the silicone polymer solution 120 will splash, while if the spin coating speed is too slow, it will affect the quality of the borosilicate glass film 140 formed.

[0089] In one embodiment, the concentration of polysiloxane raw material is controlled at 5%, the spin coating speed is 1000 r / min, the heat treatment temperature is 130°C, the power of ultrasonic 241 is set to 500W, the ultrasonic 241 irradiation time is controlled within 3 minutes, and the ozone concentration is adjusted to 10%. Through the above preparation method, a 480nm borosilicate glass film 140 can be obtained. Since the silicon oxide polymer has good fluidity, no other auxiliary methods are needed to improve its fluidity, thus it has excellent cavity-filling ability. In addition, the formation of borosilicate glass film 140 can be achieved by using ultrasonic 241-assisted oxidation, without the need for a vaporization device and high-temperature heating, which can reduce the process temperature of semiconductor structure 100, thereby reducing the preparation cost of semiconductor structure 100 and improving the quality and reliability of borosilicate glass film 140.

[0090] Secondly, please refer to Figure 3 As shown, this application provides a semiconductor structure 100, which can be fabricated using the semiconductor structure fabrication method of the first aspect described above. The semiconductor structure 100 includes a substrate 110, which has trenches 111. The trenches 111 are filled with dielectric films such as borosilicate glass film 140 to electrically isolate multiple metal lines in the substrate 110 through the borosilicate glass film 140.

[0091] Thirdly, embodiments of this application provide a semiconductor structure fabrication apparatus 200, which can be used to fabricate, for example, the semiconductor structure 100 described above, by means of the semiconductor structure fabrication method described above.

[0092] Please refer to Figure 5As shown, the semiconductor structure fabrication apparatus 200 provided in this application embodiment includes: a first chamber, in which a spin coating dielectric device 210 is disposed, the spin coating dielectric device 210 includes a spin coating stage 211 and a spin coating head 212, the spin coating head 212 is located above the spin coating stage 211 and can rotate about the vertical axis of the spin coating stage 211; wherein, the spin coating stage 211 is configured to carry a substrate 110, and the spin coating head 212 is configured to spin coat a silicon oxide polymer solution 120 on the surface of the substrate 110.

[0093] In some embodiments, a substrate 110 is disposed on a spin coater 211, and a silicone polymer solution 120 is sprayed onto the surface of the substrate 110. The spin coater head 212 rotates relative to the spin coater 211 about the axis of the spin coater 211 to spin coat the silicone polymer solution 120 on the surface of the substrate 110 to form a silicone polymer layer 130 by spin coating dielectric process.

[0094] In other embodiments, the spin coater head 212 is positioned above the spin coater stage 211 but remains stationary, while the spin coater stage 211 can rotate about its own axis, so that the relative movement between the spin coater stage 211 and the spin coater head 212 spin coats the silicone polymer solution 120 on the surface of the substrate 110 to form a silicone polymer layer 130.

[0095] In addition, the spin coater head 212 can also move vertically up and down relative to the spin coater table 211, or the spin coater table 211 can move vertically up and down, so that the substrate 110 can be placed on or removed from the spin coater table 211.

[0096] In some embodiments, a heating stage 220 is further provided in the first chamber. The heating stage 220 is configured to heat the substrate 110 to bake the silicon oxide polymer layer 130 formed on the surface of the substrate 110. The baking temperature threshold can be between 120°C and 150°C so that the solvent in the silicon oxide polymer layer 130 evaporates during the baking process.

[0097] In some embodiments, the heating stage 220 and the spin coater 211 can be independent structures, that is, the spin coater 211 and the heating stage 220 are two independent structures. After the substrate 110 forms a silicon oxide polymer layer 130 on the spin coater 211 through the spin coating dielectric process, the substrate 110 is then transported to the heating stage 220 for heat treatment.

[0098] In some embodiments, the first chamber may include two separate sub-chambers, with the spin coating dielectric device located in one sub-chamber and the heating unit located in the other sub-chamber.

[0099] In other embodiments, the heating stage 220 and the spin coater 211 can be an integrated structure, that is, the heating stage 220 and the spin coater 211 are integrated into one structure and located in the same chamber; in this way, the transport steps of the semiconductor structure 100 in the preparation process can be reduced, thereby improving the preparation efficiency. In addition, the integration of the semiconductor structure preparation apparatus 200 can be increased, and the overall volume of the preparation apparatus 200 can be reduced.

[0100] In some embodiments, the heating machine 220 may be electrically connected to a power source, and the heating machine 220 starts heating when it is connected to the power source.

[0101] In some embodiments, the semiconductor structure fabrication apparatus 200 further includes a second chamber, in which a support stage 230 and an ultrasonic device 240 located above the support stage 230 are disposed. The support stage 230 is configured to support a substrate 110, and the ultrasonic device 240 is configured to irradiate the substrate 110 with ultrasonic waves 241.

[0102] It is understandable that by irradiating the silicon-oxygen polymer layer 130 on the substrate 110 with ultrasonic waves 241 for, for example, less than 3 minutes, the bonding between silicon ions and carbon ions in the silicon-oxygen polymer layer 130 can be disrupted to form a porous silicon layer containing silicon hydroxide bonds.

[0103] In addition, the preparation apparatus 200 also includes a gas channel 250 communicating with the second chamber. The gas channel 250 is configured to supply an oxidizing gas, such as ozone, into the second chamber, whereby the ozone reacts with a silicon hydroxide bond to form a borosilicate glass membrane 140.

[0104] In other embodiments, please refer to Figure 6 As shown, the heating stage 220 can also be disposed within the second chamber, and the heating stage 220 and the support stage 230 within the second chamber are integrally formed. The gas channel 250 is located above the second chamber; for example, the connection between the gas channel 250 and the second chamber is located directly above the support stage 230. This ensures that when ozone, for example, is supplied to the second chamber through the gas channel 250, the concentration of ozone on the surface of the substrate 110 can be maintained, thereby improving the conversion efficiency of forming the borosilicate glass film 140.

[0105] In some other implementations, the first chamber and the second chamber can also be integrated into one chamber (not shown in the figure). For example, the spin coater 211, the heating machine 220 and the support platform 230 can be set up independently, or the spin coater 211, the heating machine 220 and the support platform 230 can also be integrated into a single structure, thereby reducing the overall volume of the preparation device 200 and improving the integration.

[0106] In some embodiments, the fabrication apparatus 200 further includes a transport device (not shown), exemplary of which the transport device is disposed between a first chamber and a second chamber and is configured to transport a substrate 110 in the first chamber to the second chamber.

[0107] Alternatively, the conveying device can also be used to convey substrates between different sub-chambers within the first chamber, or between different machines within the same chamber. The specific method of conveying substrates can be determined according to actual needs, and no restrictions are imposed here.

[0108] For example, the conveying device can be a robot or a robotic arm to convey the substrate 110 to be prepared into the first chamber, and to convey the substrate 110 in the first chamber into the second chamber, or to remove the prepared substrate 110 from the second chamber. In this way, the automation level of the semiconductor structure preparation apparatus 200 can be improved, thereby improving the preparation efficiency of the semiconductor structure 100.

[0109] Additionally, please continue to refer to Figure 6 The semiconductor structure fabrication apparatus 200 also includes a gas extraction device, and the second chamber has an exhaust passage 260. Exemplarily, the gas extraction device is configured to extract byproduct gases generated in the second chamber via the exhaust passage 260.

[0110] Specifically, during the process of the silicon-oxygen polymer layer 130 on the surface of substrate 110 being irradiated by ultrasonic waves 241 and reacting with oxidizing gas to form borosilicate glass film 140, byproduct gases such as CO2 and H2O are generated. In this embodiment, by setting an exhaust channel 260 and an extraction device connected to the exhaust channel 260, the generated byproduct gases are extracted by the extraction device.

[0111] The air extraction device can be, for example, a power device such as a pump.

[0112] In the semiconductor structure, semiconductor structure fabrication method, and fabrication apparatus provided in this application embodiment, a silicon oxide polymer layer is formed by spin-coating a silicon oxide polymer solution on the substrate surface using a spin-coating dielectric process. The silicon oxide polymer layer is then heat-treated, with a heat treatment temperature threshold of 120°C to 150°C to evaporate the solvent in the silicon oxide polymer solution. Subsequently, the heat-treated silicon oxide polymer layer is irradiated with ultrasound for a preset duration to form a porous silicon layer containing silicon hydroxide bonds. An oxidizing gas is provided to the porous silicon layer, and the oxidizing gas reacts with the hydroxide bonds in the porous silicon layer to form a borosilicate glass film. The borosilicate glass film fills the trenches. In this way, the formation of the borosilicate glass film can be achieved by using an ultrasound-assisted oxidation method without the need for a vaporization device and high-temperature heating. This reduces the process temperature of the semiconductor structure, thereby reducing the fabrication cost of the semiconductor structure and improving the quality and reliability of the borosilicate glass film.

[0113] The various embodiments or implementation methods described in this specification are presented in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referred to each other.

[0114] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for preparing a semiconductor structure, comprising: providing a substrate having a trench formed therein; providing a siloxane polymer solution to a surface of the substrate, the siloxane polymer solution including a dopant element, the dopant element including boron and phosphorus; spin coating the siloxane polymer solution to form a siloxane polymer layer using a spin-on dielectric process; performing a thermal treatment on the siloxane polymer layer, the thermal treatment having a temperature threshold of 120-150 °C; irradiating the siloxane polymer layer with ultrasonic waves for a predetermined time period to form a porous silicon layer having a silicon hydroxide bond; and providing an oxidizing gas to the porous silicon layer, the oxidizing gas reacting with the silicon hydroxide bond in the porous silicon layer to form a borophosphosilicate glass film, the borophosphosilicate glass film filling the trench.

2. The method of claim 1, wherein the temperature threshold of the thermal treatment on the siloxane polymer layer is 130 °C.

3. The method of claim 1, wherein the siloxane polymer solution includes polysiloxane, triethylboron, triethyl phosphate, and a solvent.

4. The method of claim 3, wherein the concentration of the polysiloxane is 5-20%.

5. The method of any one of claims 1-4, wherein the oxidizing gas includes at least one of ozone, oxygen, nitroxyl, dinitrogen oxide, nitrogen dioxide, and carbon oxide.

6. The method of claim 5, wherein the oxidizing gas includes ozone.

7. The method of claim 6, wherein the concentration of the ozone is 5-15%.

8. The method of any one of claims 1-4, wherein the spin-on dielectric process has a spin speed of 500-1500 rpm.

9. The method of any one of claims 1-4, wherein the ultrasonic waves have a frequency of 40-60 kHz and / or a power of 500-600 W.

10. The method of any one of claims 1-4, wherein the siloxane polymer layer is irradiated with the ultrasonic waves for a time period of 3 min or less.

11. A semiconductor structure, comprising: a substrate having a trench formed therein; and a borophosphosilicate glass film filling the trench, the semiconductor structure being prepared using the method of any one of claims 1-10.

12. An apparatus for preparing a semiconductor structure, the apparatus being configured to perform the method of any one of claims 1-10, comprising: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ A first chamber, a spin-on dielectric device and a heating machine table are arranged in the first chamber, the spin-on dielectric device comprises a spin-on machine table and a spin-on head, the spin-on head is above the spin-on machine table and can rotate around a vertical axis of the spin-on machine table relative to the spin-on machine table; wherein the spin-on machine table is configured to carry a substrate, the spin-on head is configured to spin-on a silicon-oxygen polymer solution on the surface of the substrate; the heating machine table is configured to heat the substrate on the spin-on machine table; A second chamber, a carrying table and an ultrasonic device above the carrying table are arranged in the second chamber, the carrying table is configured to carry the substrate, and the ultrasonic device is configured to irradiate ultrasonic waves to the substrate; A gas channel is in communication with the second chamber, and the gas channel is configured to provide an oxidizing gas into the second chamber.

13. The device for preparing a semiconductor structure according to claim 12, wherein, A conveying device is further arranged between the first chamber and the second chamber, and the conveying device is configured to convey the substrate in the first chamber into the second chamber.

14. The device for preparing a semiconductor structure according to claim 12, wherein, An exhaust device is further arranged, and the second chamber has an exhaust channel, and the exhaust device is configured to exhaust by-product gas generated in the second chamber through the exhaust channel.

15. The device for preparing a semiconductor structure according to claim 12, wherein, The heating machine table and the spin-on machine table are an integrated structure, and the heating machine table is configured to be electrically connected with a power supply.

Images