A method and apparatus for smoothing and patterning diamond based on catalytic energy field assisted etching

Abstract

The application discloses a diamond smoothing and patterning method and device based on catalysis energy field assisted etching, belongs to the technical field of diamond smoothing and patterning, and realizes the smoothing or patterning of diamond through the joint action of a catalyst and an energy field. The part of the diamond in contact with the catalyst disk is subjected to catalysis of the catalyst, so that the part of the diamond in contact with the catalyst is subjected to etching reaction or graphitization reaction with oxygen atoms, the part of the diamond not in contact with the catalyst disk is hardly subjected to reaction, and then the diamond generates a structure corresponding to the surface of the catalyst disk. The material removal rate of the diamond is remarkably improved, and damage to the surface and subsurface of the diamond is avoided.

Description

Technical Field

[0001] This invention belongs to the field of diamond smoothing and patterning technology, specifically relating to a method and apparatus for diamond smoothing and patterning based on catalytic energy field assisted etching. Background Technology

[0002] Diamond, due to its unique crystal structure, possesses excellent electrical, mechanical, thermal, and optical properties, demonstrating immense application value in the semiconductor, machining tool, heat sink, and laser side window fields. Single-crystal diamond, with its wide bandgap, high electron and hole mobility, high breakdown electric field, low dielectric constant, and high thermal conductivity, is an ideal material for high-frequency, high-power electronic devices in the semiconductor field. In the machining tool field, the high hardness and wear resistance of polycrystalline diamond make it a superior choice for manufacturing cutting tools and abrasives. In the heat sink field, diamond's extremely high thermal conductivity and low coefficient of thermal expansion make it suitable as a heat sink material for high-power semiconductors, microwave devices, and integrated circuits. Furthermore, diamond's excellent light transmission and good mechanical properties also make it valuable for applications such as laser side windows and infrared optical windows.

[0003] However, diamond's extremely high hardness and chemical stability make it extremely difficult to process, and traditional processing methods are insufficient for its effective handling. Furthermore, diamond requires an ultra-smooth surface to meet the demands of certain applications. In semiconductor device manufacturing, damage or scratches on the diamond surface can severely impair carrier transport, increase device power consumption, and reduce performance and reliability. In optical applications, scratches or uneven surfaces can cause laser scattering, reducing the transmittance and imaging quality of optical components. Typically, for high-precision semiconductor and optical applications, diamond surface roughness must reach the nanometer level, and surface accuracy must reach sub-micrometer or even higher standards to meet increasingly stringent application requirements.

[0004] Currently, various diamond processing methods have many limitations. Machining methods often damage the subsurface of diamond, and the processed diamond surface is prone to scratches and cracks. Chemical machining has low material removal rates, high chemical reagent costs, and environmental pollution; it also requires stringent processing environments and easily results in uneven surfaces. Plasma processing equipment is expensive, uneven energy distribution leads to scratches and pits on the surface, requires strict gas control, and has limited processing area. Thermal processing easily induces phase transformations in diamond, resulting in low processing accuracy and high energy consumption. Laser processing equipment has high costs and maintenance expenses, is prone to thermal stress causing surface microcracks, and requires highly skilled operators. Summary of the Invention

[0005] This invention provides a method and apparatus for smoothing and patterning diamond based on catalytic energy field-assisted etching, which improves processing efficiency while reducing surface and subsurface damage to diamond.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for diamond smoothing and patterning based on catalytic energy field-assisted etching, comprising:

[0008] The diamond surface to be processed is tightly bonded to an ultra-smooth or patterned catalyst disk, maintaining uniform pressure between the two. The diamond and catalyst disk are placed in an oxygen-filled container and an energy field is applied. Under the influence of the energy field and the catalytic action of the catalyst, the portion of the diamond in contact with the catalyst disk undergoes an etching or graphitization reaction with oxygen atoms, resulting in a structure on the diamond corresponding to the surface of the catalyst disk. The ultra-smooth catalyst disk is used to smooth the diamond surface, while the patterned catalyst disk is used to pattern the diamond surface.

[0009] Furthermore, the energy field is a thermal field, a combination of a thermal field and a plasma field, or a combination of a thermal field and an ultraviolet light field, wherein the temperature of the thermal field is 300℃~800℃.

[0010] Furthermore, this includes the following steps:

[0011] SA1. Fix the diamond and catalyst disk in the fixture so that the diamond surface to be processed is in close contact with the ultra-smooth or patterned catalyst disk, and the pressure between the diamond and the catalyst disk is uniform and stable.

[0012] SA2. Place the assembled fixture into the container, seal the container and evacuate it.

[0013] SA3. Introduce oxygen into the container;

[0014] SA4. Heat the container to 300–800°C and maintain this temperature. The unpaired electrons present in the catalyst disk interact with the carbon atoms on the diamond surface, promoting the sp... 3 diamond-to-sp structure 2 The graphitization of the structure; simultaneously, the catalyst undergoes an oxidation reaction with oxygen, generating reactive oxygen species; graphitization or sp... 3 To sp 2 During the phase transition process, carbon atoms on the surface of diamond react chemically with active oxygen to generate carbon dioxide or carbon monoxide gas, thus achieving the smoothing or patterning of the diamond.

[0015] Furthermore, in the SA3, when oxygen is introduced into the container, the oxygen flow rate is 0.1 mL / min - 1 L / min.

[0016] Furthermore, this includes the following steps:

[0017] SB1. Fix the diamond and catalyst disk in the fixture so that the diamond surface to be processed is in close contact with the ultra-smooth or patterned catalyst disk, and the pressure between the diamond and the catalyst disk is uniform and stable.

[0018] SB2. Place the assembled fixture between the upper and lower electrode plates in the container, seal the container and evacuate it; the upper electrode plate is connected to the radio frequency power supply, and the lower electrode plate is grounded;

[0019] SB3. Introduce gas into the container, wherein the gas is oxygen and argon / helium, or a mixture of oxygen, nitrogen and argon / helium;

[0020] SB4. Heat the container to 300-800°C and maintain the temperature; turn on the radio frequency power supply to form an alternating electric field between the upper and lower plates;

[0021] The alternating electric field causes free electrons in the gas to generate charged particles and active free radicals. These charged particles oscillate continuously in the electric field and collide with gas molecules, forming a self-sustaining discharge phenomenon. The capacitive coupling between the upper and lower electrode surfaces causes electrons and ions to respond alternately within the electric field cycle, forming a sheath and maintaining plasma stability. During plasma generation, electrons collide with oxygen molecules, exciting and decomposing them to generate oxygen free radicals. Under the catalysis of the catalyst, sp... 3 diamond-to-sp structure 2 Graphitization or sp. of the structure 3 To sp 2 During the phase transition process, carbon atoms on the surface of diamond react with oxygen free radicals in the plasma to generate carbon dioxide or carbon monoxide gas, which then evaporates, thus achieving smoothing or patterning of the diamond in a plasma atmosphere.

[0022] Furthermore, this includes the following steps:

[0023] SC1. Fix the diamond and catalyst disk in the fixture so that the diamond surface to be processed is in close contact with the ultra-smooth or patterned catalyst disk, and the pressure between the diamond and the catalyst disk is uniform and stable.

[0024] SC2. Place the assembled fixture into a container, seal the container and evacuate it; the container is equipped with an ultraviolet lamp, and the ultraviolet light emitted by the ultraviolet lamp has a wavelength of less than 225nm;

[0025] SC3. Introduce oxygen into the container;

[0026] SC4. Turn on the ultraviolet lamp and heat the container to 300-800°C and maintain this temperature; irradiate the diamond surface with ultraviolet light to promote the reaction between the carbon atoms of the diamond and active oxygen; simultaneously, the ultraviolet light promotes the reaction of diamond sp... 3 carbon to sp 2 Graphite phase transformation, graphitization or sp 3 To sp 2 During the phase transition process, carbon atoms react with active oxygen. In addition, ultraviolet light excites oxygen molecules in the vacuum chamber to produce highly active oxygen, which promotes the reaction between oxygen and diamond, generating carbon dioxide or carbon monoxide gas that evaporates. Under the catalytic action of the metal catalyst, and in conjunction with the ultra-smooth or patterned surface of the catalyst disk, smoothing or patterning is achieved.

[0027] Secondly, the present invention provides a diamond smoothing and patterning apparatus based on catalytic energy field-assisted etching, comprising:

[0028] The fixture is used to fit the surface of the diamond to be processed against the surface of the catalyst disk and to maintain uniform and stable pressure between the surface of the diamond to be processed and the catalyst disk.

[0029] Catalytic disks are used for etching or graphitization reactions of diamond.

[0030] A container used to provide a sealed reaction space for diamonds;

[0031] A heating device for heating and controlling the temperature of the container.

[0032] Furthermore, the container is equipped with an ultraviolet lamp or an electrode plate.

[0033] Furthermore, the clamp includes an upper clamp and a lower clamp, and the upper clamp has several through-holes for light transmission.

[0034] Furthermore, it also includes a pressure gauge used to monitor the internal pressure of the container.

[0035] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0036] This paragraph has been deleted because it's a duplicate of the next paragraph. The next paragraph is a revised version of this one.

[0037] This invention provides a diamond smoothing and patterning method based on catalytic energy field-assisted etching. Under three energy field atmospheres—thermal oxygen, plasma, and ultraviolet light thermal oxygen—the metal catalyst of the catalyst disk catalyzes the graphitization of diamond and promotes the generation of active oxygen. The active oxygen reacts rapidly with the diamond during graphitization or phase transition to generate volatile gases, significantly improving the diamond material removal rate. Unlike chemical mechanical processing, which requires expensive chemical reagents, and inductively coupled plasma and laser processing, which require costly equipment and high maintenance fees, this method avoids these high-cost factors, effectively reducing processing costs. This method achieves surface etching through close contact between the catalyst disk and the diamond, effectively avoiding scratches and cracks caused by mechanical processing and preventing damage to the diamond surface and subsurface. By selecting catalyst disks with different structures and adjusting the energy field parameters, this method can flexibly achieve diamond smoothing and patterning.

[0038] The invention provides a diamond smoothing and patterning device based on catalytic energy field-assisted etching, comprising a catalyst disk and a device for providing the energy field. The catalytic action of the catalyst disk promotes diamond graphitization, and combined with the synergistic effect of a thermal field, plasma field, or ultraviolet light field, processing efficiency can be significantly improved. This device can flexibly achieve diamond surface smoothing or complex patterning by replacing the ultra-smooth or differently patterned catalyst disks and adjusting parameters such as energy field type (thermal oxidation, plasma, ultraviolet photothermal oxidation), temperature, and gas flow rate. This device does not rely on high-cost chemical reagents, complex plasma sources, or laser systems; it has a simple structure and low maintenance costs, making it suitable for large-scale industrial applications. Attached Figure Description

[0039] Figure 1 This is a flowchart of a diamond smoothing and patterning method based on catalytic energy field assisted etching according to an embodiment of the present invention;

[0040] Figure 2 This is a schematic diagram of the clamp that holds the diamond and the catalyst disk according to an embodiment of the present invention;

[0041] Figure 3 This is a schematic diagram illustrating the diamond smoothing and patterning principle according to an embodiment of the present invention;

[0042] Figure 4 This is a schematic diagram of a device for diamond processing in a hot and oxygen atmosphere according to an embodiment of the present invention;

[0043] Figure 5 This is a schematic diagram of a device for diamond processing in a plasma atmosphere according to an embodiment of the present invention;

[0044] Figure 6 This is a schematic diagram of a device for diamond processing under ultraviolet light, heat, and oxygen atmosphere according to an embodiment of the present invention;

[0045] Figure 7This is a schematic diagram of the upper clamp according to an embodiment of the present invention;

[0046] Figure 8 This is a schematic diagram of the lower clamp according to an embodiment of the present invention;

[0047] Figure 9 SEM image of the diamond surface in its initial state;

[0048] Figure 10 The image is a smoothed SEM image obtained under a hot and oxygen-rich atmosphere.

[0049] Figure 11 White light interference image of the initial state of the diamond surface;

[0050] Figure 12 White light interference image of a diamond surface after treatment at 500℃ for 2 hours in an oxygen atmosphere;

[0051] Figure 13 White light interference image of a diamond surface after treatment at 600℃ for 2 hours in an oxygen atmosphere;

[0052] Figure 14 White light interference image of a diamond surface after treatment at 700℃ for 2 hours in an oxygen atmosphere.

[0053] Figure label:

[0054] 1-Clamping fixture; 2-Diamond; 3-Catalyst plate; 4-Vacuum tube; 5-Vacuum chamber; 61-Upper electrode plate; 62-Lower electrode plate; 7-UV lamp; 8-Heating furnace; 9-Vacuum pump; 10-Pressure gauge; 11-Upper clamping fixture; 12-Lower clamping fixture; 13-Light transmission hole; 14-RF power supply; 15-Oxygen cylinder; 16-Argon cylinder; 17-Nitrogen cylinder; 18-Mass flow meter; 19-Temperature controller. Detailed Implementation

[0055] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0056] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0057] It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or may be interposed with another element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or may be interposed with another element. The terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., used herein to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention.

[0058] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0059] Diamond, due to its strong chemical inertness, requires relatively harsh environments (such as extremely high temperatures) to react with oxygen. (See reference) Figure 1 A method for smoothing and patterning diamond based on catalytic energy field-assisted etching, the specific process of which is shown in the attached instruction manual. Figure 1 As shown. The specific solution is as follows:

[0060] Using a jig 1, the surface of the diamond 2 to be processed is tightly bonded to an ultra-smooth or patterned catalyst disk 3 under uniform pressure. Placed in an oxygen atmosphere, under the influence of a corresponding energy field (thermal field, plasma field, ultraviolet light field), due to the catalytic effect of the catalyst, the portion of the diamond 2 in contact with the catalyst undergoes an etching or graphitization reaction with oxygen atoms, while the portion not in contact with the catalyst hardly reacts, thus generating a structure corresponding to the surface of the catalyst disk 3. Therefore, by using an ultra-smooth planar catalyst disk 3, the diamond 2 substrate can be smoothed; and by using a patterned surface of the catalyst disk 3, the surface of the diamond 2 can be patterned.

[0061] The etching reaction of diamond 2 can be catalyzed in the following three atmospheric environments.

[0062] Thermo-oxygen atmosphere: The clamp 1 that holds the diamond 2 and the catalyst disk 3 is placed in a heatable vacuum tube 4, oxygen is introduced, and the heating temperature is increased, with the temperature range controlled between 300 and 800°C.

[0063] Plasma Atmosphere: The clamp 1 is placed in a heatable vacuum chamber 5, gas is introduced and heated, and a high-frequency alternating voltage is applied between two electrodes 6 installed in the vacuum chamber 5. Electrons in the gas respond to the electric field and gain energy, becoming excited and generating a uniform plasma between the two electrodes 6. The capacitively coupled plasma contains a large number of oxygen free radicals and can also promote an increase in ambient temperature. The gas is oxygen and argon / helium, or a mixture of oxygen, nitrogen, and argon / helium.

[0064] Ultraviolet light, heat, and oxygen atmosphere: The fixture 1 is placed in a heatable vacuum chamber 5, oxygen is introduced and heated, and the ultraviolet lamp 7 installed on the top of the vacuum chamber is turned on to irradiate the diamond 2.

[0065] All three different atmospheres can promote the activation reaction between diamond 2 and catalyst disk 3, thereby achieving the smoothing and patterning of diamond 2.

[0066] refer to Figure 2 and Figure 7 The clamp 1 plays a crucial role. It clamps the diamond 2 and the catalyst disk 3, fixing them in the correct position and ensuring contact between them, allowing the catalyst disk 3 to assist in the etching process of the diamond 2. The clamp 1 includes an upper clamp 11 made of stainless steel, a lower clamp 12 made of stainless steel, and bolts and nuts. The upper clamp 11 has multiple through-holes 13 with a diameter of 1mm-5mm, distributed above the diamond 2 clamped by the clamp 1. In an ultraviolet-heat-oxygen atmosphere, these through-holes increase the area of ​​the diamond 2's upper surface exposed to ultraviolet light. Because diamond is chemically inert, it requires energy to promote its activation reaction with the catalyst disk 3. More ultraviolet light exposure means that the diamond 2 can absorb more energy, accelerating its etching with oxygen atoms.

[0067] refer to Figure 8 The lower clamp 12 has a groove in the middle that fits with the catalyst disk 3, which can fix the catalyst disk 3 in the correct position. By controlling the fixing torque of the bolt and nut with a torque wrench, the upper clamp 11 and the lower clamp 12 are pressed evenly, so that the clamp 1 can clamp the diamond 2 and the catalyst disk 3. This creates a uniform and stable pressure between the surface of the diamond 2 to be processed and the catalyst disk 3, ensuring that the catalyst disk 3 effectively plays an auxiliary role in the etching reaction, while achieving uniform etching on the surface of the diamond 2.

[0068] The metal catalyst material used in catalyst disk 3 is an iron-based, nickel-based, chromium-based, or cobalt-based metal material. During diamond etching, the metal catalyst plays two roles: first, it catalyzes the graphitization of diamond; as a transition metal, the unpaired d electrons of the metal catalyst can lower the energy barrier for the transformation of diamond to graphite, accelerating the graphitization process. Second, the metal catalyst promotes the generation of reactive oxygen species; the metal catalyst can be catalytically oxidized to produce highly reactive oxygen species, which readily react with graphitized or sp... 3 To sp 2 Diamond reaction during phase transition.

[0069] The auxiliary etching reaction of catalyst disk 3 during the etching process is as follows: the metal catalyst (represented by element M) can catalyze the graphitization of diamond. Graphitized diamond is more likely to react with highly reactive oxygen species, which is beneficial for diamond removal. The principle of metal catalyst catalyzing diamond graphitization can be explained as follows: the d orbitals of metal catalyst materials such as iron and nickel contain unpaired electrons. These unpaired electrons are highly reactive and easily interact with the carbon atoms of diamond to form chemical bonds, thereby breaking the sp atoms of diamond. 3 Structure, prompting diamond to refract into sp 2 Graphite structural transformation. Simultaneously, the metal catalyst can be catalytically oxidized, generating highly reactive oxygen species, which readily react with graphitized or sp... 3 To sp 2 The diamond reaction during phase transition. The metal catalyst M undergoes an oxidation reaction in a hot, oxygen-rich atmosphere, combining with oxygen to form a metal oxide MO. x The reaction equation is aM + bO2 → MaO 2b For example, when MO is generated, the reaction is 2M + O₂ → 2MO. After the metal oxide is formed, its surface can adsorb and dissociate oxygen molecules, producing highly reactive oxygen species, with the reaction being MaO. 2b +n / 2O2→MaO 2b ·n[O*], where O* represents surface active oxygen. During the diamond etching stage, active oxygen readily attacks graphitized or sp... 3 To sp 2 During the phase transition process, diamond forms CO or CO2, with the reaction formula being C(diamond) + MaO. 2b ·n[O*]→CO n ↑+MaO 2b-n For example, if CO2 is generated, the reaction is C + 2[O*] → CO2↑. Reactive oxygen species react with graphitization or sp... 3 To sp 2 The reaction rate of diamond during the phase transition is much faster than that of sp. 3 The diamond structure. The generated CO or CO2 gas evaporates, thus achieving efficient etching of diamond 2.

[0070] Reference Figure 3 The ultra-smooth catalyst disk 3 can smooth the diamond 2, while the catalyst disk 3 with a certain pattern structure can pattern the diamond 2, that is, to create a concave pattern on the surface of the diamond 2 that matches the raised pattern of the catalyst disk 3. Specifically, during the smoothing process, the ultra-smooth surface of the catalyst disk 3 is tightly attached to the rough surface of the diamond 2 under the action of the clamp 1. The protrusions on the rough surface of the diamond 2 come into contact with the metal catalyst. Under the catalytic action of the catalyst, the carbon atoms in the protrusions undergo etching or graphitization reactions with oxygen, while the carbon atoms that are not in contact with the catalyst hardly react, so the protrusions are gradually removed, thereby achieving the smoothing of the diamond 2. During the patterning process, the raised pattern of the catalyst disk 3 with a certain pattern structure comes into contact with the diamond 2 and reacts, forming a corresponding concave pattern on the surface of the diamond 2. Other parts hardly react, thereby achieving the patterning of the diamond 2.

[0071] The following are specific embodiments. It should be noted that these embodiments are preferred examples of the present invention and are intended for those skilled in the art to understand the present invention, but the present invention is not limited to these embodiments.

[0072] Example 1

[0073] This embodiment describes a smoothing and patterning scheme for diamond 2 in a hot and oxygen atmosphere. A schematic diagram of the equipment for smoothing and patterning diamond 2 in a hot and oxygen atmosphere is shown below. Figure 4 As shown. The equipment mainly consists of a heatable vacuum tube 4, a heating furnace 8, a mass flow meter 18, an oxygen cylinder 15, a vacuum pump 9, and a pressure gauge 10. The main body of the equipment is composed of the heating furnace 8 and the vacuum tube 4. A temperature controller 19 is installed on the heating furnace 8. The vacuum tube 4 passes through the heating furnace 8, with the mass flow meter 18 and the oxygen cylinder 15 connected sequentially on the left side via pipes, and the pressure gauge 10 and the vacuum pump 9 connected sequentially on the right side. The heatable vacuum tube 4 provides a sealed environment for the reaction, ensuring that the smoothing and patterning process of diamond 2 proceeds smoothly without external interference. The temperature controller 19 controls the temperature of the hot oxygen atmosphere, keeping the reaction in a high-temperature environment. The mass flow meter controls the oxygen flow rate, providing an oxygen atmosphere for the reaction environment. The pressure gauge monitors the internal pressure of the heatable vacuum tube 4.

[0074] A smoothing and patterning method under a hot and oxidative atmosphere includes the following steps:

[0075] The diamond 2 to be smoothed or patterned is fixed on the fixture 1, ensuring its surface to be processed is tightly fitted to the ultra-smooth or patterned catalyst disk 3. Using bolts and nuts, the fixing torque is adjusted uniformly with a torque wrench to ensure consistent pressure between the diamond 2 and the catalyst disk 3. The assembled fixture 1 is placed in the middle of a heatable vacuum tube 4, and the heating tube is sealed. The vacuum pump is turned on, and the pressure gauge reading is observed to be less than 100 Pa to ensure a vacuum environment is achieved. Oxygen is introduced, and the oxygen flow rate is controlled at 0.1 mL / min-1 L / min using a mass flow meter. The heating furnace 8 is turned on, and the heating temperature is set to 300-800℃, preferably 500℃, using the temperature controller 19 of the heating furnace 8. The gas pressure during the reaction process is monitored by a pressure gauge. If the pressure fluctuation is too large, the oxygen flow rate or vacuum pump power is adjusted to maintain pressure stability. Maintaining this temperature for 1-2 hours allows for the smoothing and patterning of the diamond 2 in a hot oxygen atmosphere.

[0076] In this embodiment, parameters such as temperature and gas flow rate can be adjusted by controlling the mass flow meter 18 and the temperature controller 19 to achieve different degrees of smoothing and patterning of diamond 2. Different oxygen flow rates will change the oxygen concentration in the reaction system: at low flow rates, the oxygen concentration is low, and the etching reaction is relatively mild. At high flow rates, the oxygen concentration is high, and the etching reaction is more intense, removing more material in a short time. A suitable flow rate can be selected according to the specific smoothing and patterning requirements of diamond 2. The temperature is controlled at 300-800℃ because diamond 2 has high chemical stability, and this temperature range can provide activation energy for its reaction with oxygen, allowing the reaction to proceed; at the same time, this temperature range is suitable for the catalytic activity of metal catalysts, which can effectively promote the graphitization and etching reaction of diamond 2; under different atmospheres such as thermal oxygen, plasma, and ultraviolet thermal oxygen, this temperature can synergistically promote the reaction; in addition, it can avoid problems such as phase transformation of diamond 2 and excessive oxidation of catalyst caused by excessively high temperature, and slow reaction and accumulation of intermediate products caused by excessively low temperature. The oxidation time is controlled between 1 and 2 hours, mainly determined by the desired surface roughness of the diamond or the etching depth required for patterning. The longer the oxidation time, the greater the degree of surface oxidation, and the surface roughness initially decreases and then increases with time. The etching depth increases with increasing oxidation time.

[0077] Under a thermo-oxidative atmosphere, the main mechanism for the smoothing and patterning of diamond 2 is the catalytic effect of the metal catalyst and the synergistic reaction of the thermo-oxidative environment. Metal catalysts, such as transition metals like iron and nickel, possess unpaired electrons in their d orbitals. These electrons interact with carbon atoms on the diamond surface, promoting the smoothing and patterning of sp... 3 diamond-to-sp structure 2The graphitization transformation of the structure lowers the activation energy of the diamond-oxygen reaction. Simultaneously, in an oxygen-rich environment, the metal catalyst undergoes an oxidation reaction with oxygen to generate oxides, which can further produce highly reactive oxygen species readily reacting with diamond. In a high-temperature and oxygen-rich environment of 300–800℃, graphitization or sp... 3 To sp 2 During the phase transition process, carbon atoms on the diamond surface react chemically with active oxygen to generate carbon dioxide or carbon monoxide gas, which then evaporates, thus removing diamond 2. Because the catalyst disk 3 is ultra-smooth or has a certain pattern, carbon atoms on the diamond 2 surface in contact with the catalyst react preferentially, while carbon atoms on other uncontacted parts hardly react. As the etching reaction continues, the surface of diamond 2 is eventually smoothed or patterned.

[0078] Figure 9 The image shows the initial SEM image of the diamond surface. The image also shows the SEM image after the diamond has been smoothed by being treated in a 500℃ hot oxygen atmosphere for 2 hours. Figure 10 As shown, by Figure 10 As can be seen, the scratches have been completely removed, achieving surface flattening.

[0079] Figure 11 A white light interference image of the diamond surface before smoothing, from Figure 11 As can be seen, the initial surface was uneven, with a surface roughness Sa of 3.519 nm. After being treated in a hot-oxygen atmosphere at 500℃ for 2 hours, the white light interference image is as follows. Figure 12 As shown, the surface roughness decreased to 1.251 nm Sa.

[0080] The white light interference image after treatment in a thermo-oxygen atmosphere at 600℃ for 2 hours is as follows. Figure 13 As shown, although the surface roughness decreased slightly, the surface quality was worse than that obtained after treatment at 500℃; the white light interferometry image after treatment at 700℃ in a hot oxygen atmosphere for 2 hours is shown below. Figure 14 As shown, the surface etching degree increases, and the roughness increases significantly.

[0081] Example 2

[0082] This embodiment describes a method for smoothing and patterning diamond 2 in a plasma atmosphere. A schematic diagram of the equipment for smoothing and patterning diamond 2 in a plasma atmosphere is shown below. Figure 5As shown. The experimental apparatus includes a heatable vacuum chamber 5, an upper electrode plate 61 and a lower electrode plate 62, a radio frequency power supply 14, a temperature controller, a mass flow meter 18, an oxygen cylinder 15, an argon cylinder 16, a nitrogen cylinder 17 or a mixed gas source, a vacuum pump 9, and a pressure gauge 10. The main body of the equipment consists of the vacuum chamber 5. The upper electrode plate 61 and the lower electrode plate 62 are installed inside the vacuum chamber 5. The upper electrode plate 61 is connected to the radio frequency power supply, and the lower electrode plate 62 is grounded. A temperature controller is installed outside the vacuum chamber 5. There is a channel on each side of the bottom plate of the vacuum chamber 5. The left channel connects to the mass flow meter and the oxygen cylinder 15, argon cylinder 16, and nitrogen cylinder 17 via pipes. The right channel connects to the pressure gauge 10 and the vacuum pump 9 in sequence. The vacuum chamber 5 has good sealing and high-temperature resistance, providing a vacuum-sealed environment for the reaction and reducing interference from external impurities. The upper and lower electrode plates are made of materials with good electrical conductivity and are installed inside the vacuum chamber 5. When a high-frequency alternating voltage is applied between the upper and lower electrodes, the gas is ionized to generate plasma. Parameters such as the shape, size, and spacing of the upper and lower electrodes affect the distribution and uniformity of the plasma, thus influencing the etching effect on diamond 2. The radio frequency power supply 14 provides a high-frequency alternating voltage of 13.56 MHz to provide energy for plasma generation. By adjusting the output power of the radio frequency power supply, the energy and quantity of electrons in the plasma can be changed, thereby affecting the concentration of active particles such as oxygen free radicals and achieving different etching effects on diamond 2. Oxygen cylinders, argon cylinders, nitrogen cylinders, or mixed gas sources serve as gas supply sources, providing the necessary reactive and auxiliary gases for the plasma environment. The heating temperature of the vacuum chamber 5 is 300–800℃, and the gas flow rate is controlled at 0.1 mL / min–1 L / min.

[0083] In specific operation, the clamp 1 holding the diamond 2 and the catalyst disk 3 is placed between the upper and lower electrodes installed in the vacuum chamber 5. After closing the vacuum chamber 5 and evacuating it, gas is introduced in a certain proportion. The gas is oxygen and argon / helium, or oxygen, nitrogen and argon / helium. The radio frequency power supply 14 is turned on, and a high-frequency alternating voltage of 13.56MHz is applied. The voltage intensity is controlled by the radio frequency power supply. At the same time, the temperature inside the vacuum chamber 5 is controlled at 300-800℃ using a temperature controller.

[0084] In a plasma atmosphere, the mechanism for achieving smoothing and patterning of diamond 2 involves the generation of capacitively coupled plasma, the formation of reactive oxygen species, and the catalytic effect of metal catalysts.

[0085] The principle of capacitively coupled plasma generation: When a high-frequency alternating voltage of 13.56 MHz is applied between the upper and lower plates of the vacuum chamber 5, an alternating electric field is formed between the plates. When gas is introduced, the electric field accelerates the movement of free electrons in the gas, giving them sufficient kinetic energy to collide with neutral gas molecules, initiating ionization, excitation, or dissociation processes, generating a large number of charged particles (electrons and ions) and active free radicals (such as oxygen free radicals). These charged particles continuously oscillate and collide with gas molecules in the electric field, forming a self-sustaining discharge phenomenon. The capacitive coupling effect on the surfaces of the upper and lower plates causes electrons and ions to respond alternately within the electric field period. Electrons, due to their small mass, respond rapidly, while ions, due to their large mass, move with lag, resulting in the formation of a sheath and maintaining plasma stability. During plasma generation, high-energy electrons collide with oxygen molecules, exciting and decomposing the oxygen molecules, thereby generating a large number of oxygen free radicals. Simultaneously, the capacitively coupled plasma generation process also promotes the temperature rise within vacuum chamber 5, keeping the entire vacuum chamber 5 at a relatively high reaction temperature (still below 800℃), ensuring the effective execution of the diamond etching reaction. Under the catalysis of the metal catalyst, sp... 3 diamond-to-sp structure 2 The graphitization of the structure. These graphitizations, or sp... 3 To sp 2 During the phase transition process, carbon atoms on the surface of diamond react with a large number of oxygen free radicals in the plasma to generate carbon dioxide or carbon monoxide gas that evaporates, thus removing diamond 2 under the plasma atmosphere. Combined with an ultra-smooth or patterned catalyst disk 3, the smoothing and patterning of diamond 2 can be achieved.

[0086] Example 3

[0087] This embodiment describes a method for smoothing and patterning diamond 2 under ultraviolet light, heat, and oxygen atmosphere. A schematic diagram of the equipment for smoothing and patterning diamond 2 under ultraviolet light, heat, and oxygen atmosphere is shown below. Figure 6 As shown. The experimental setup mainly consists of a heatable vacuum chamber 5, an ultraviolet lamp 7, a temperature controller 19, a mass flow meter 18, and an oxygen cylinder 15. The main body of the equipment is the heatable vacuum chamber 5. An ultraviolet lamp 7 is installed in the upper part of the vacuum chamber 5. A temperature controller is installed outside the vacuum chamber 5. There are two channels on the lower left and right sides of the vacuum chamber 5. The left channel is connected to the mass flow meter 18 and the oxygen cylinder 15 via pipes, and the right channel is connected to a pressure gauge and a vacuum pump. Similar to a plasma atmosphere, the vacuum chamber 5 provides a vacuum-sealed environment for the reaction, reducing interference from external impurities. The temperature of the hot oxygen atmosphere is controlled at 300–800℃ by the temperature controller 19, keeping the reaction in a high-temperature environment. The oxygen flow rate is controlled at 0.1 mL / min–1 L / min by the mass flow meter, providing an oxygen atmosphere for the reaction. The ultraviolet lamp 7 emits ultraviolet light to promote the generation of reactive oxygen species and the reaction of diamond sp.3 carbon to sp 2 The graphite phase transition occurs when the wavelength of ultraviolet light is less than 225 nm.

[0088] In practice, the clamp 1 holding the diamond 2 and the catalyst plate 3 is placed below the ultraviolet lamp 7 installed in the vacuum chamber 5, ensuring that the side of the clamp 1 with the through-hole 13 faces the ultraviolet lamp 7. After closing the vacuum chamber 5 and evacuating it, oxygen is introduced; the ultraviolet lamp 7 is turned on, and the ultraviolet light intensity is adjusted so that the ultraviolet light wavelength is less than 225nm. The temperature of the vacuum chamber 5 is maintained at 300-800℃ using the temperature controller 19.

[0089] The mechanism of smoothing and patterning of diamond under ultraviolet light and a thermo-oxidative atmosphere can be summarized as the effect of ultraviolet light and the catalytic effect of metal catalysts. Ultraviolet light can excite the carbon atoms in diamond and promote the smoothing and patterning of diamond sp atoms. 3 carbon to sp 2 Graphite phase transformation and the promotion of reactive oxygen species (ROS) generation. Diamond has a band gap energy of 5.45 eV. According to the photon energy formula E = h * c / λ (where E is the photon energy, h is Planck's constant, c is the speed of light, and λ is the wavelength of light), when the wavelength of light is less than 225 nm, the photon energy is sufficient to induce electron transitions in diamond, forming electron-hole pairs. Therefore, irradiating the surface of diamond with ultraviolet light with a wavelength less than 225 nm can excite the carbon atoms in diamond, promoting their reaction with reactive oxygen species. Simultaneously, ultraviolet light can also promote the sp(s) phase transition in diamond. 3 carbon to sp 2 Graphite phase transformation, graphitization or sp 3 To sp 2 Carbon atoms in the phase transition process react more readily with reactive oxygen species. Furthermore, ultraviolet light can excite oxygen molecules in the vacuum chamber, generating highly reactive oxygen species such as oxygen free radicals, thereby promoting the reaction between oxygen and diamond, producing carbon dioxide or carbon monoxide gases that evaporate. Under the catalytic action of the metal catalyst, and in conjunction with the ultra-smooth or patterned surface of the catalyst disk 3, the diamond 2 can achieve smoothing and patterning under ultraviolet light-heated oxygen atmosphere.

[0090] In summary, this invention provides a method and apparatus for diamond smoothing and patterning based on catalytic energy field-assisted etching. This method utilizes the assisted etching effect of an ultra-smooth or patterned catalytic disk to achieve diamond etching in a thermo-oxygen atmosphere, a plasma energy field, and an ultraviolet light energy field. This effectively reduces processing costs, avoids damage to the diamond surface and subsurface, and allows for flexible diamond smoothing and patterning by adjusting the energy field parameters.

[0091] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

[0092] The term "constituting of" in describing a combination should include the identified elements, components, parts, or steps, as well as other elements, components, parts, or steps that do not substantially affect the essential novel features of the combination. The use of the terms "comprising" or "including" to describe combinations of elements, components, parts, or steps herein also contemplates embodiments that are essentially composed of such elements, components, parts, or steps. The use of the term "may" herein is intended to indicate that any described attribute included by "may" is optional.

[0093] Multiple elements, components, parts, or steps can be provided by a single integrated element, component, part, or step. Alternatively, a single integrated element, component, part, or step can be divided into multiple separate elements, components, parts, or steps. The use of "a" or "an" to describe an element, component, part, or step does not imply the exclusion of other elements, components, parts, or steps.

[0094] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this teaching should not be determined by reference to the above description, but rather by reference to the foregoing claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed inventive subject matter.

Claims

1. A method for smoothing and patterning diamond based on catalytic energy field-assisted etching, characterized in that, Includes the following steps: SA1. Fix the diamond (2) and the catalyst disk (3) in the fixture (1) so that the surface of the diamond (2) to be processed is in close contact with the ultra-smooth or patterned catalyst disk (3) and the pressure between the diamond (2) and the catalyst disk (3) is uniform and stable. SA2. Place the assembled fixture (1) into the container, seal the container and evacuate it; SA3. Introduce oxygen into the container; SA4. Heat the container to 300~800℃ and maintain it. The unpaired electrons in the catalyst disk (3) interact with the carbon atoms on the diamond surface, causing the sp³ structure diamond to transform into sp² structure graphite. At the same time, the catalyst reacts with oxygen to produce active oxygen. During the graphitization or sp³ to sp² phase transition, the carbon atoms on the diamond surface react with active oxygen to produce carbon dioxide or carbon monoxide gas, thus achieving the smoothing or patterning of the diamond (2).

2. A method for smoothing and patterning diamond based on catalytic energy field-assisted etching, characterized in that, Includes the following steps: SB1. Fix the diamond (2) and the catalyst disk (3) in the fixture (1) so that the surface of the diamond (2) to be processed is in close contact with the ultra-smooth or patterned catalyst disk (3) and the pressure between the diamond (2) and the catalyst disk (3) is uniform and stable. SB2. Place the assembled fixture (1) between the upper electrode plate (61) and the lower electrode plate (62) in the container, seal the container and evacuate it; the upper electrode plate (61) is connected to the radio frequency power supply (14), and the lower electrode plate (62) is grounded; SB3. A gas is introduced into the container, wherein the gas is oxygen and argon, oxygen and helium, a mixture of oxygen, nitrogen and argon, or a mixture of oxygen, nitrogen and helium. SB4. Heat the container to 300~800℃ and maintain it; turn on the radio frequency power supply (14) to form an alternating electric field between the upper electrode (61) and the lower electrode (62); The alternating electric field causes free electrons in the gas to generate charged particles and active free radicals. The charged particles continuously oscillate and collide with gas molecules in the electric field, forming a self-sustaining discharge phenomenon. The capacitive coupling between the upper electrode (61) and the lower electrode (62) causes electrons and ions to respond alternately within the electric field period, forming a sheath and maintaining plasma stability. During the plasma generation process, electrons collide with oxygen molecules, and oxygen molecules are excited and decomposed, thereby generating oxygen free radicals. Under the catalysis of the catalyst, sp³ structure diamond is transformed into sp² structure graphite. The carbon atoms on the surface of diamond during the graphitization or sp³ to sp² phase transition process react with oxygen free radicals in the plasma to generate carbon dioxide or carbon monoxide gas and volatilize, realizing the smoothing or patterning of diamond (2) in the plasma atmosphere.

3. A method for smoothing and patterning diamond based on catalytic energy field-assisted etching, characterized in that, Includes the following steps: SC1. Fix the diamond (2) and the catalyst disk (3) in the fixture (1) so that the surface of the diamond (2) to be processed is in close contact with the ultra-smooth or patterned catalyst disk (3) and the pressure between the diamond (2) and the catalyst disk (3) is uniform and stable. SC2. Place the assembled fixture (1) into the container, seal the container and evacuate it; the container is equipped with an ultraviolet lamp (7), and the ultraviolet light emitted by the ultraviolet lamp (7) has a wavelength of less than 225nm; SC3. Introduce oxygen into the container; SC4. Turn on the ultraviolet lamp (7) and heat the container to 300~800℃ and maintain it; use ultraviolet light to irradiate the diamond surface to promote the reaction of diamond carbon atoms with active oxygen; at the same time, ultraviolet light promotes the transformation of diamond sp³ carbon to sp² graphite phase, and the carbon atoms in the graphitization or sp³ to sp² phase transformation process react with active oxygen; in addition, ultraviolet light excites oxygen molecules in the vacuum cavity to produce highly active oxygen, promotes the reaction of oxygen with diamond, and generates carbon dioxide or carbon monoxide gas to evaporate. Under the catalytic action of the metal catalyst, in conjunction with the ultra-smooth or patterned surface of the catalyst disk (3), smoothing or patterning is achieved.

4. The diamond smoothing and patterning method based on catalytic energy field-assisted etching according to claim 1, characterized in that, In the SA3, when oxygen is introduced into the container, the oxygen flow rate is 0.1 mL / min - 1 L / min.

5. A diamond smoothing and patterning apparatus based on catalytic energy field-assisted etching, used to implement the method described in any one of claims 1-3, characterized in that, include: The fixture (1) is used to make the surface of the diamond (2) to be processed fit with the surface of the catalyst disk (3) and to keep the pressure of the surface of the diamond (2) to be processed and the catalyst disk (3) uniform and stable. Catalyst disk (3) is used for etching or graphitization of diamond (2); A container used to provide a closed reaction space for the diamond (2); A heating device for heating and controlling the temperature of the container; The container is equipped with an ultraviolet lamp (7) or an electrode plate; The clamp (1) includes an upper clamp (11) and a lower clamp (12), and the upper clamp has several through light-transmitting holes (13).

6. The diamond smoothing and patterning device based on catalytic energy field-assisted etching according to claim 5, characterized in that, It also includes a pressure gauge (10) for monitoring the internal pressure of the container.

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