Method and apparatus for etching a sample

Abstract

A method (200) and apparatus for etching a sample are disclosed. The method (200) includes cooling (201) a surface of the sample, wherein the surface of the sample is covered with a layer of etchant material or covered with an etchant material to form a layer of etchant material on the surface of the sample. The surface of the sample and the layer of etchant material are cooled to a cooling temperature that is below an activation temperature of the etchant material. Further, the method (200) includes heating (203) (i.e., activating) the cooled (i.e., non-active) layer of etchant material and the surface of the sample at one or more selected locations to activate the etchant material and etch the surface of the sample at the one or more selected locations with the activated etchant material. The method (200) can enable micro- or nano-fabrication and enable precise control of structures in locally etched samples without the need to use photoresist material or lift-off processes because the layer of etchant material is a non-active, solid film at low temperature conditions.

Description

Technical Field

[0001] This invention relates to material preparation and processing. More specifically, this invention relates to a method and apparatus for etching samples (e.g., semiconductor material samples). Background Technology

[0002] Traditional semiconductor device fabrication techniques typically involve etching processes, which usually require a photolithography process prior to etching to define the etch pattern on a photoresist layer. After a lift-off process removes (or retains) the exposed positive (or negative) photoresist, wet or dry etching is performed, with controllable etching depth. In material micromachining, laser shaping or laser-assisted etching is used to perform 3D processing. Due to the intense localized heating induced by lasers, samples can be physically or chemically processed with micrometer-scale spatial resolution.

[0003] Laser etching is a process that creates markings on parts and products by melting their surfaces. Laser etching falls under the broader category of laser marking, which also includes laser engraving and laser annealing. Laser etching is very versatile and can be used on most metals. To create raised markings, a laser beam delivers a large amount of energy to a small area, causing the material surface to melt and expand, resulting in a black, white, or gray color. For laser etching and / or engraving, the resolution is typically greater than 10 μm, and the process is limited to metallic materials.

[0004] Wet etching is an economical and simple process, but it is isotropic in most cases, making it difficult to obtain etched profiles with high aspect ratios. Dry etching is anisotropic, thus enabling higher aspect ratios, but it is more complex and expensive. Both wet and dry etching are based on photolithography and therefore rely on photoresist materials.

[0005] Laser-assisted selective etching (LSE) benefits from the significant difference in etching rates between the laser-heated and unexposed areas, where the surface of the unexposed area is still slightly etched. Thermal diffusion in the liquid also makes the etching resolution inferior to optical resolution. LSE is generally only applicable to a few glass materials because it requires that the sample material hardly undergoes any chemical reaction at room temperature. Furthermore, the sample surface can be damaged even if it is not exposed to the laser. Third, laser-induced heating has a significant diffusion length, thus the etching resolution is significantly inferior to optical resolution. Summary of the Invention

[0006] The purpose of this invention is to provide an improved method and apparatus for etching samples such as semiconductor material samples.

[0007] The above and other objectives are achieved by the subject matter claimed in the independent claims. Other implementations are apparent from the dependent claims, the specification, and the drawings.

[0008] According to a first aspect, a method for etching a sample is provided. The method according to the first aspect includes the step of cooling the surface of the sample, wherein the surface of the sample is covered with an etchant material layer or covered with an etchant material to form an etchant material layer on the surface of the sample. The surface of the sample and the etchant material layer are cooled to a cooling temperature below the activation temperature of the etchant material.

[0009] Furthermore, the method according to the first aspect includes the steps of heating (i.e. activating) a cooled (i.e., inactive) etchant material layer and the surface of the sample at one or more selected locations to activate the etchant material, and etching the surface of the sample at one or more selected locations with the activated etchant material.

[0010] The method according to the first aspect supports the execution of micro- or nano-fabrication to precisely control the structure in locally etched samples without the use of photoresist materials or stripping processes, because the etchant material layer is an inactive solid film under low-temperature conditions. The method according to the first aspect can be used for micro- and nano-fabrication of chip-level products, such as electronic chips, photonic chips, laser chips, waveguide chips, super-optics, nano / microelectromechanical systems, micro-LED arrays, holographic optical elements, Fresnel optics, etc.

[0011] In another possible implementation, the step of heating (i.e., activating) the surface of a cooled (i.e., inactive) etchant material layer and sample at one or more selected locations includes: heating (i.e. activating) the surface of the cooled (i.e., inactive) etchant material layer and sample at one or more selected locations via heat transfer using a heating tip (e.g., an atomic force microscope (AFM) or any scanning probe microscope heating tip). This supports the efficient heating and activation of the surface of the cooled (i.e., inactive) etchant material layer and sample at one or more selected locations, for example, achieving a resolution below 10 nm.

[0012] In another possible implementation, the method also includes measuring the etching depth in real time, for example, using atomic force microscopy or any scanning probe microscopy technique. This allows for precise real-time monitoring and control of the etching depth, achieving, for example, accuracy below 1 nm.

[0013] In another possible implementation, the method further includes controlling one or more of the following parameters: the distance from the surface of the etchant material layer to the tip; the etching depth; the heating duration; the tip temperature; the heating power used to heat the tip; and / or the tip scanning rate. This allows for control of the etching rate and adjustment of the etching resolution as needed.

[0014] In another possible implementation, the method also includes scanning the heated tip along one or more selected locations, for example, using atomic force microscopy or any scanning probe microscopy technique. This allows for etching any selected location of the sample at a specified etching depth.

[0015] In another possible implementation, the step of heating (i.e. activating) the surface of a cooled (i.e., inactive) etchant material layer and a sample at one or more selected locations includes: heating (i.e. activating) the surface of the cooled (i.e., inactive) etchant material layer and the sample at one or more selected locations using laser radiation from a laser. This supports remotely heating and activating the surface of the cooled (i.e., inactive) etchant material layer and the sample at one or more selected locations.

[0016] In another possible implementation, the method further includes guiding (i.e. focusing) laser radiation from a laser to one or more selected locations via optical components to heat the surface of a cooled (i.e., inactive) etchant material layer and a sample at one or more selected locations. This enables efficient heating and activation of the cooled (i.e., inactive) etchant material layer and sample surface at one or more selected locations, achieving, for example, resolution on the order of 100 nm.

[0017] In another possible implementation, the method also includes measuring the etching depth in real time using optical components such as an optical interferometer. This supports real-time monitoring and precise control of the etching depth, achieving, for example, an accuracy of less than 10 nm.

[0018] In another possible implementation, directing laser radiation from a laser to one or more selected locations on the surface of a cooled etchant material layer and a sample comprises: projecting laser radiation from a laser through an etching pattern or etching mask onto one or more selected locations on the surface of the cooled etchant material layer and the sample. It should be understood that the etching pattern or etching mask need not be in contact with the surface of the sample or the etchant material layer. As used herein, projecting laser radiation through an etching pattern or etching mask means directing the laser onto the etching mask, which only allows selected portions of the laser to irradiate the surface of the etchant material layer and the sample at one or more selected locations.

[0019] In another possible implementation, the method further includes controlling one or more of the following parameters: laser radiation power; laser radiation exposure time; laser radiation beam size; laser radiation beam shape; laser radiation pulse shape; laser radiation pulse repetition rate; and / or laser radiation power density. This allows for control of the etching rate and adjustment of the etching resolution as needed.

[0020] In another possible implementation, directing laser radiation from the laser to one or more selected locations on the surface of the cooled (i.e., inactive) etchant material layer and the sample involves scanning one or more selected locations on the surface of the etchant material layer and the sample with laser radiation from the laser. This allows for etching any selected location of the sample at a specified etching depth.

[0021] In another possible implementation, the method according to the first aspect also includes controlling the cooling temperature.

[0022] In another possible implementation, cooling the sample surface and the etchant material layer to a cooling temperature below the activation temperature of the etchant material includes using a cryostat, particularly a liquid or cold nitrogen cryostat, a liquid or cold helium cryostat, or a thermoelectric cryostat, to cool the sample surface (covered or to be covered by the etchant material layer) to a cooling temperature below the activation temperature of the etchant material.

[0023] In another possible implementation, the sample includes semiconductor sample material, metal sample material, alloy sample material, glass sample material, solid sample material and / or any combination of these materials.

[0024] In another possible implementation, the surface of the sample is covered with an etchant material to form an etchant material layer on the sample surface by evaporating the etchant material and guiding the evaporated etchant material to the sample surface through a feedthrough (if needed), thereby depositing the etchant material on the cooled surface of the sample.

[0025] In another possible implementation, an etchant material layer is formed on the sample surface by spraying etchant material onto the sample surface and covering the sample surface with etchant material.

[0026] In another possible implementation, the etchant material includes acidic etchant materials and / or alkaline etchant materials.

[0027] In another possible implementation, the step of heating the cooling etchant material layer and the surface of the sample at one or more selected locations to activate the cooling etchant material and etching the surface of the sample at one or more selected locations with the activated etchant material includes: heating the cooling etchant material layer and the surface of the sample at one or more selected locations to activate the cooling etchant material and performing anisotropic etching on the surface of the sample at one or more selected locations with the activated etchant material.

[0028] According to a second aspect, an apparatus for etching a sample is provided. The apparatus according to the second aspect includes a cooling device for cooling the surface of the sample, wherein the surface of the sample is covered with an etchant material layer or covered with an etchant material to form an etchant material layer on the surface of the sample, and wherein the surface of the sample and the etchant material layer are cooled by the cooling device to a cooling temperature below the activation temperature of the etchant material.

[0029] Furthermore, the apparatus according to the second aspect includes a heating device for heating (i.e. activating) a cooled (i.e., inactive) etchant material layer and the surface of a sample at one or more selected locations to activate the etchant material and etch the surface of the sample at one or more selected locations with the activated etchant material.

[0030] The apparatus according to the second aspect supports the performance of micro- or nano-fabrication to precisely control the local etching of structures in samples without the use of photoresist materials or stripping processes, because the etchant material layer is an inactive solid film at low temperatures. The apparatus according to the second aspect can be used for micro- and nano-fabrication of chip-level products such as electronic chips, photonic chips, laser chips, waveguide chips, super-optics, nano / microelectromechanical systems, micro-LED arrays, holographic optical elements, Fresnel optics, etc.

[0031] In another possible implementation, the heating device includes a heating tip for heating (i.e. activating) a cooled (i.e., inactive) etchant material layer and the sample surface at one or more selected locations via heat transfer. The heating tip could be an atomic force microscopy (AFM) heating tip.

[0032] In another possible implementation, the device also includes a sensor device for measuring the etching depth in real time using an atomic force microscope or any scanning probe microscope technique.

[0033] In another possible implementation, the device also includes a control unit for controlling one or more of the following parameters: distance from the etchant surface to the tip; etching depth; heating duration; tip temperature; tip heating power; and / or scan rate.

[0034] In another possible implementation, the apparatus includes a device for scanning a heated tip along one or more selected locations using atomic force microscopy or any scanning probe microscopy technique. This allows for etching any selected location of the sample at a specified etching depth.

[0035] In another possible implementation, the heating device includes a laser for heating (i.e. activating) the cooled (i.e., inactive) etchant material layer and the surface of the sample at one or more selected locations by laser radiation from the laser.

[0036] In another possible implementation, the device also includes optical components for guiding (i.e. focusing) laser radiation from the laser to one or more selected locations on the surface of the cooled etchant material layer and the sample, so as to heat the cooled (i.e. inactive) etchant material layer and the surface of the sample at one or more selected locations.

[0037] In another possible implementation, the device also includes a sensor device for measuring the etching depth in real time using optical components such as an optical interferometer.

[0038] In another possible implementation, the device includes a control unit for controlling one or more of the following parameters: the power of the laser radiation; the exposure time of the laser radiation; the beam size of the laser radiation; the beam shape of the laser radiation; the pulse shape of the laser radiation; the pulse repetition rate of the laser radiation; and / or the power density of the laser radiation.

[0039] In another possible implementation, optical components are used to scan one or more selected locations of the etchant material layer and the surface of the sample with laser radiation from the laser.

[0040] In another possible implementation, optical components are used to project laser radiation from the laser through an etched pattern onto one or more selected locations in the etchant material layer and onto the surface of the sample.

[0041] In another possible implementation, the device includes a control unit for controlling the cooling temperature.

[0042] In another possible implementation, the cooling device includes a cryostat, particularly a liquid or cold nitrogen cryostat, a liquid or cold helium cryostat, or a thermoelectric cryostat, for cooling the surface of the sample and the layer of etchant material to a cooling temperature below the activation temperature of the etchant material.

[0043] In another possible implementation, the sample includes semiconductor sample material, metal sample material, alloy sample material, glass sample material, solid sample material and / or any combination of these materials.

[0044] In another possible implementation, the apparatus includes a deposition apparatus for covering the surface of a sample with an etchant material to form an etchant material layer on the surface of the sample by evaporating the etchant material and guiding the evaporated etchant material onto the surface of the sample through a feedthrough.

[0045] In another possible implementation, the apparatus includes a deposition device for forming an etchant material layer on the surface of the sample by spraying etchant material onto the surface of the sample and covering the surface of the sample with etchant material.

[0046] In another possible implementation, the etchant material includes acidic etchant materials and / or alkaline etchant materials.

[0047] In another possible implementation, a heating device is used to heat (i.e. activate) a cooled (i.e. inactive) etchant material layer and the surface of the sample at one or more selected locations to activate the etchant material and perform anisotropic etching on the surface of the sample at one or more selected locations with the activated etchant material.

[0048] One or more embodiments will be described in detail in the accompanying drawings and the following description. Other features, objects, and advantages will be apparent from the specification, drawings, and claims. Attached Figure Description

[0049] The embodiments of the present invention will now be described in more detail with reference to the accompanying drawings, in which: Figure 1a A schematic diagram of an apparatus for etching a sample is shown in one embodiment, the etching being based on activating an etchant material by laser radiation; Figure 1b A schematic diagram of an apparatus for etching a sample, provided in another embodiment, is shown, wherein the etching is based on activating an etchant material by laser radiation; Figure 1c A schematic diagram of an apparatus for etching a sample, provided in another embodiment, is shown, the etching being based on activating an etchant material by heating a tip; Figure 2 A flowchart of a method for etching a sample, provided in one embodiment, is shown.

[0050] In the following text, the same reference numerals refer to the same or at least functionally equivalent features. Detailed Implementation

[0051] In the following description, reference is made to the accompanying drawings, which form part of this invention, illustrating by way of description specific aspects of embodiments of the invention or specific aspects in which embodiments of the invention may be used. It is understood that embodiments of the invention can be used in other aspects and include structural or logical variations not shown in the drawings. Therefore, the following detailed description is not intended to be limiting, and the scope of the invention is defined by the appended claims.

[0052] For example, it should be understood that the disclosure relating to the described method also applies to the corresponding apparatus or system for performing the method, and vice versa. For instance, if one or more specific method steps are described, the corresponding apparatus may include one or more units, such as functional units for performing the described one or more method steps (e.g., a unit performing one or more steps; or multiple units, each performing one or more of the multiple steps), even if such one or more units are not explicitly described or shown in the drawings. Furthermore, for example, if a specific apparatus is described based on one or more units (e.g., functional units), the corresponding method may include a step for performing the function of one or more units (e.g., a step performing the function of one or more units; or multiple steps, each performing the function of one or more of the multiple units), even if such one or more steps are not explicitly described or shown in the drawings. Further, it is understood that, unless otherwise explicitly stated, features of the various exemplary embodiments and / or aspects described herein may be combined with each other.

[0053] Figure 1a A schematic diagram of an apparatus 100 for etching a sample 150 is shown in one embodiment. In one embodiment, the sample 150 may include semiconductor sample materials, such as silicon wafers, metal sample materials, alloy sample materials, glass sample materials, and / or solid sample materials.

[0054] like Figure 1a As shown, the apparatus 100 includes a cooling device 110 for cooling at least one surface of the sample 150, preferably the entire sample 150. Figure 1aIn the illustrated embodiment, the cooling device 110 includes: a cryostat cooling device 110 having a cooling unit 110a for generating a cooling temperature; and a cooling chamber or sample chamber 110b for housing the sample 150. In one embodiment, the cryostat cooling device 110 may be a low-vibration cryostat cooling device 110 with amplitudes significantly lower than the etching resolution. In one embodiment, for example, the cryostat cooling device 110 may include a liquid or cold nitrogen cryostat 110, a liquid or cold helium cryostat 110, or a thermoelectric cryostat 110, for generating cooling temperatures, for example, as low as about 77 Kelvin and about 4 Kelvin, respectively. As will be described in more detail below, at least one surface of the sample 150 is covered with an etchant material layer 140 and / or covered with etchant material to form an etchant material layer 140 on the surface of the sample 150. The surface of the sample 150 and the etchant material layer 140 are cooled by the cooling device 110 to a cooling temperature below the activation temperature of the etchant material. In one embodiment, the etchant material may include an acidic etchant material and / or an alkaline etchant material. A possible etchant material for the silicon sample 150 is a 45% KOH solution with a melting point of 243 Kelvin. A possible etchant material for the GaAs sample is a 75% H3PO4 solution with a melting point of 255.8 Kelvin. In one embodiment, the activation temperature of the etchant material may be its melting point.

[0055] like Figure 1a As shown, the apparatus 100 also includes a heating device 120, in the form of a laser 120, for generating laser radiation, i.e., a highly focused laser beam 120a. The heating device 120 (e.g., the laser 120) is used to locally heat (i.e., activate) the cooled (i.e., solid and inactive) etchant material layer 140 and the surface of the sample 150 at one or more selected locations by laser radiation, to activate the etchant material, for example by locally converting the etchant material into a liquid phase, and to locally etch the surface of the sample 150 at one or more selected locations with the activated (e.g., liquefied) etchant material. This activates the local etching process while leaving adjacent non-exposed areas completely unaffected or minimally affected. Thus, in one embodiment, due to local heating and continuous cooling of the surrounding material, the apparatus 100 can perform anisotropic etching on the surface of the sample 150, thereby enabling the etching of structures with very high aspect ratios, which in the semiconductor industry can only be performed on most semiconductor materials using dry etching.

[0056] It should be understood that conventional anisotropic etching is known to use materials such as SiO2, Si3N4, GaAs, InGaAs, AlGaAs, Al2O3, and Si [amorphous (100) crystalline]. These materials are typically very expensive and cannot be wet-etched, requiring only dry etching, which further necessitates RIE equipment and photolithography systems. Therefore, a complete conventional anisotropic etching system can often cost millions of euros. The embodiments disclosed herein can significantly reduce these costs while still providing anisotropic etching because cheaper wet etching materials, such as any chemical liquid solvent, are available, a photolithography system is not required, and / or maintenance is eliminated, avoiding the use of large amounts of toxic gases and safety concerns.

[0057] exist Figure 1a In the illustrated embodiment, device 100 further includes a cryogenic optical component 130, such as an objective lens 130, for guiding (i.e. focusing) laser radiation 120a from laser 120 onto one or more selected locations on the surface of sample 150 and / or the cooled etchant material layer 140, to locally heat the surface of sample 150 and / or the cooled (i.e., solid and inactive) etchant material layer 140 at one or more selected locations with laser radiation 120a. In one embodiment, optical component 130 may include one or more optical elements, such as lenses or objectives, and is located inside or outside the cooling chamber 110b of cooling device 110.

[0058] exist Figure 1a In one embodiment, the optical component 130 is used, for example, to scan one or more selected locations on the surface of the sample 150 and / or the etchant material layer 140 with laser radiation 120a from the laser 120 by tilting and / or moving the optical component 130 and / or the laser 120 relative to the sample 150. Figure 1b A variation of this embodiment is shown for etching sample material to achieve a desired pattern on the surface of sample 150, wherein laser 120 and / or optical components 130 are used to project laser radiation 120a from laser 120 through etching pattern 125 onto one or more selected locations on the surface of sample 150 and / or etchant material layer 140. In other words, by projecting laser radiation 120a through etching pattern 125, the projected laser radiation 120a has a high energy density, which can heat the etchant material layer 140 to a liquid phase, thereby etching the projected structure, such as... Figure 1bAs shown. Since etching is thermally activated, the etching depth can be controlled by adjusting the laser power or exposure time. After the etching stage described above, the etched surface of sample 150 can be rinsed with deionized water (DI water) at room temperature. Since the unexposed portions of the surface of sample 140 are protected by the remaining solid (i.e., frozen etchant material) layer 140, which is chemically non-reactive, no residual contamination will occur due to rinsing.

[0059] Although Figure 1a and Figure 1b In the illustrated embodiment, localized heating is achieved through laser radiation 120a generated by laser 120 and absorbed by sample 150 and / or etchant material layer 140, but... Figure 1c In another embodiment shown, the heating device may include a heating tip 121, a device 122 for moving the heating tip 121 (i.e., for vertically adjusting the height of the heating tip 121 and / or horizontally scanning the heating tip 121 along selected locations on the surface of the sample 150 and the etchant material layer 140), and a unit 123 for heating the heating tip 121. In other words, in Figure 1c In the illustrated embodiment, heating is performed on selected locations on the surfaces of the etchant material layer 140 and the sample 150, based on heat transfer with the heating tip 121, for example via atomic force microscopy (AFM). The heating tip 121 is used to locally heat (i.e., activate) the cooled (i.e., solid and inactive) surfaces of the etchant material layer 140 and the sample 150 at one or more selected locations via heat transfer. In this embodiment, the heating tip 121 can be applied (i.e., near or in the environment) to the etchant material layer 140 to locally heat it to a liquid phase. This activates the local etching process while keeping adjacent non-melting areas completely unaffected, which remain cooled by the cooling device 110. The etching thickness can be measured in real time and controlled by the control unit 160 of the device 100 based on atomic force measurement or any other scanning probe technology (e.g., magnetic force microscopy, tunneling microscopy, Kelvin force microscopy, etc.). By performing scanning motion of the heating tip 121 (due to the action of device 122) and controlling the depth, a specific etched sample material pattern can be formed within the sample 150. Manufacturing can be completed by coating another protective layer on the surface of sample 150 and rinsing the surface of sample 150.

[0060] like Figures 1a to 1cAs shown and as described above, in this embodiment, the apparatus 100 may further include a control unit 160 for controlling one or more of the following parameters: the power of the laser radiation 120a; the exposure time of the laser radiation 120a; the beam size of the laser radiation 120a; the beam shape of the laser radiation 120a; the pulse shape of the laser radiation 120a; the pulse repetition rate of the laser radiation 120a; and / or the power density of the laser radiation 120a. Therefore, by means of the control unit 160, for example, the beam size, shape, pulse shape, pulse repetition rate, and power density of the laser radiation 120a can be optimized for any given target structure to achieve optimal fidelity of the etching result. In one embodiment, the control unit 160 may also be used to control the cooling temperature generated by the cooling device 100. Figure 1c In the illustrated embodiment, the control unit 160 may be used to control one or more of the following parameters: the distance from the surface of the etchant material layer 140 to the tip 121; the etching depth; the heating duration; the tip temperature; the heating power used to heat the tip 121; and / or the scanning rate of the tip 121.

[0061] It should be understood that the etching technique disclosed herein has the following advantages compared to traditional photolithography-based etching techniques. First, it eliminates the need for a mask, thus eliminating the need for photoresist. This avoids all associated photolithography processes, including photolithography, photoresist development, and stripping. Second, the etching technique disclosed herein allows for flexible definition and adjustment of the etching pattern, whereas in traditional etching techniques, the etching pattern is defined during the photolithography process and cannot be modified afterwards. Third, using the etching technique disclosed herein, the etching depth can be controlled at different sample locations, and the etching depth can be monitored locally in real time during the etching process. In traditional etching techniques, the etching depth is determined by the etching formula and plan, where all parameters are defined, and the etching depth cannot be changed. Furthermore, the etching rate is the same throughout the sample. Traditional etching techniques cannot achieve different etching depths at different sample locations, while the etching technique disclosed herein can.

[0062] For in Figure 1a and Figure 1b The laser-activated etching technique described in this context can achieve resolutions on the order of hundreds of nanometers. Scanning speeds can reach 10 micrometers per microsecond, and etching patterns can be directly projected to perform pattern-level etching in a single pass. Therefore, this etching technique is particularly suitable for large-scale chip production.

[0063] Regarding the above Figure 1cThe heated tip-activated etching technique described in this context can achieve a resolution better than 10 nm. The achievable scanning speed may be slower than laser-activated etching, for example, around 1 micrometer / second, and the etched pattern can be achieved by scanning the tip from one location to another. Therefore, this etching technique is particularly suitable for producing devices requiring extremely high spatial resolution and precision, i.e., single-electron / molecular quantum devices or other devices that cannot be achieved using optical / SEM lithography.

[0064] exist Figure 1a , Figure 1b and Figure 1c In the illustrated embodiment, apparatus 100 further includes a deposition apparatus for covering the surface of sample 150 with an etchant material to form an etchant material layer 140 on the surface of sample 150. This is achieved by evaporating liquid etchant material, for example, by heating the liquid etchant material to room temperature and guiding the evaporated etchant material onto the surface of sample 150 via feedthrough 115 or another type of capillary system. The evaporated etchant material rapidly solidifies into an etched film, i.e., the etchant material layer 140 on the cold surface of sample 150. In another embodiment, the deposition apparatus may be used to cover the surface of sample 150 with etchant material by spraying it onto the surface of sample 150 to form the etchant material layer 140 on the surface of sample 150. It should be understood that as long as these processes can deactivate the etchant material through freezing, thereby inhibiting the chemical reaction, whether by reaching a temperature below the activation temperature (i.e., thermal activation energy) or by inhibiting the transport of active material to the boundary layer between the etchant material layer 140 and the surface of the sample 150, the etchant material can be deposited as layer 140 on the surface of the sample 150. In one embodiment, the control unit 160 of the apparatus 100 can be used to control the deposition equipment to control the thickness of the etchant material layer 140 on the surface of the sample 150. In one embodiment, adjusting the thickness of the etchant material layer 140 by the control unit 160 can be used to limit the etching process, particularly to achieve a certain etching depth by depleting the etchant material.

[0065] In one embodiment, for example, the deposition of etchant material onto the surface of sample 150 using the deposition apparatus described above can be performed before, during, or after this stage of cooling the surface of sample 150. In one embodiment, the order of these processing stages can depend on the characteristics of the selected etchant material. For example, dry etchant materials can be deposited before the cooling stage, while liquid etchant materials can be deposited after sample 150 has cooled, by means of vapor-phase crystallization and / or spraying, etc. However, it should be understood that different possible sequences of deposition and cooling stages should ensure that the final surface of sample 150 and etchant material layer 140 are cooled below the activation temperature of the etchant material.

[0066] In one embodiment, another material layer, such as a protective layer or a high optical absorption material, may be disposed between the surface of sample 150 and etchant material layer 140 to increase the optical absorption of laser radiation, thereby increasing localized heating. It should be understood that for semiconductor chips, a "protective" or "protective" layer can be used to protect or enhance certain properties of the wafer surface (e.g., adhesion) during processing. The "protective" layer can be organic or inorganic, and can be insulating, semi-insulating, or conductive. Typically, such layers may include materials such as HMDS, MgO, and Al2O3.

[0067] Figure 2 An embodiment for etching is shown. Figure 1a and Figure 1b A flowchart of method 200 for sample 150 is shown. Method 200 includes a step 201 of cooling the surface of sample 150, wherein the surface of sample 150 is covered with an etchant material layer 140 and / or covered with etchant material to form an etchant material layer 140 on the surface of sample 150. As described above, the surface of sample 150 and etchant material layer 140 are cooled to a cooling temperature below the activation temperature of the etchant material. Furthermore, method 200 includes a step 203: locally heating (i.e. activating) the cooled (i.e., solid and inactive) etchant material layer 140 and the surface of sample 150 at one or more selected locations to activate the etchant material, and locally etching the surface of sample 150 at one or more selected locations with the activated etchant material.

[0068] Method 200 can be performed by device 100. Therefore, further features of method 200 come directly from the functionality of device 100 and its various embodiments described above and below.

[0069] Those skilled in the art will understand that the “blocks” (“units”) in the various figures (methods and apparatuses) represent or describe the functionality of embodiments of the invention (and are not necessarily individual “units” in hardware or software), thereby equivalently describing the functionality or features (unit = step) of apparatus embodiments and method embodiments.

[0070] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the embodiments of the described apparatus are merely exemplary. For example, the unit division is merely a logical functional division, and in actual implementation, it can be another division. For example, multiple units or components can be merged or integrated into another system, or some features can be ignored or not performed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed can be implemented by using some interface. Indirect coupling or communication connection between devices or units can be implemented electronically, mechanically, or otherwise.

[0071] The units described as discrete components may or may not be physically separate. The components shown as units may or may not be physical units, and may be located in one location or distributed across multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0072] Furthermore, in the embodiments of the present invention, the functional units can be integrated into a processing unit, or each unit can exist physically independently, or two or more units can be integrated into a unit.

Claims

1. A method (200) for etching a sample (150), characterized in that, The method (200) includes: Cooling (201) the surface of the sample (150), wherein the surface of the sample (150) is covered with an etchant material layer (140) and / or covered with an etchant material to form an etchant material layer (140) on the surface of the sample (150), and wherein the surface of the sample (150) and the etchant material layer (140) are cooled to a cooling temperature below the activation temperature of the etchant material; The etchant material layer (140) and the surface of the sample (150) are heated (203) at one or more selected locations to activate the etchant material, and the activated etchant material is used to etch the surface of the sample (150) at the one or more selected locations.

2. The method (200) according to claim 1, characterized in that, Heating (201) the surfaces of the etchant material layer (140) and the sample (150) at one or more selected locations includes heating the surfaces of the etchant material layer (140) and the sample (150) at one or more selected locations by heat transfer using a heating tip (121).

3. The method (200) according to claim 2, characterized in that, The method (200) also includes measuring the etching depth in real time using scanning probe microscopy.

4. The method (200) according to claim 2 or 3, characterized in that, The method (200) further includes controlling one or more of the following parameters: the distance from the surface of the etchant material layer (140) to the heating tip (121); the etching depth; and the heating duration; The temperature of the heating tip (121); the heating power for the heating tip (121); the scanning rate of the heating tip (121).

5. The method (200) according to any one of claims 2 to 4, characterized in that, The method also includes scanning the heated tip (121) along the one or more selected locations using scanning probe microscopy.

6. The method (200) according to any one of claims 1 to 5, characterized in that, Heating (201) the surfaces of the etchant material layer (140) and the sample (150) at one or more selected locations includes heating the surfaces of the etchant material layer (140) and the sample (150) at one or more selected locations with laser radiation (120a) from a laser (120).

7. The method (200) according to claim 6, characterized in that, The method (200) further includes guiding the laser radiation (120a) from the laser (120) to one or more selected locations of the cooling etchant material layer (140) via an optical component (130).

8. The method (200) according to claim 7, characterized in that, Directing the laser radiation (120a) from the laser (120) to one or more selected locations of the cooling etchant material layer (140) includes scanning the one or more selected locations of the cooling etchant material layer (140) with the laser radiation (120a) from the laser (120).

9. The method (200) according to claim 7, characterized in that, Directing the laser radiation (120a) from the laser (120) to one or more selected locations of the cooling etchant material layer (140) includes projecting the laser radiation (120a) from the laser (120) through an etching pattern (125) onto one or more selected locations of the cooling etchant material layer (140).

10. The method (200) according to any one of claims 6 to 9, characterized in that, The method (200) further includes controlling one or more of the following: the power of the laser radiation (120a); the exposure time of the laser radiation (120a); the beam size of the laser radiation (120a); the beam shape of the laser radiation (120a); the pulse shape of the laser radiation (120a); the pulse repetition rate of the laser radiation (120a); and / or the power density of the laser radiation (120a).

11. The method (200) according to any one of claims 1 to 10, characterized in that, The method (200) further includes controlling the cooling temperature.

12. The method (200) according to any one of claims 1 to 11, characterized in that, Cooling the surface of the sample (150) and the etchant material layer (140) to a cooling temperature below the activation temperature of the etchant material includes: cooling the surface of the sample (150) and the etchant material layer (140) to a cooling temperature below the activation temperature of the etchant material using a cryostat (110).

13. The method (200) according to any one of claims 1 to 12, characterized in that, The sample (150) includes semiconductor sample material, metal sample material, alloy sample material, glass sample material and / or solid sample material.

14. The method (200) according to any one of claims 1 to 13, characterized in that, The etchant material is evaporated and guided to the surface of the sample (150) through a feedthrough (115) to form an etchant material layer (140) on the surface of the sample (150).

15. The method (200) according to any one of claims 1 to 14, characterized in that, The etchant material is sprayed onto the surface of the sample (150) to cover the surface of the sample (150) with the etchant material, thereby forming the etchant material layer on the surface of the sample (150).

16. The method (200) according to any one of claims 1 to 15, characterized in that, The etchant material includes acidic etchant materials and / or alkaline etchant materials.

17. The method (200) according to any one of claims 1 to 16, characterized in that, Heating (203) the surface of the cooling etchant material layer (140) and the sample (150) at one or more selected locations to activate the cooling etchant material, and etching the surface of the sample (150) at one or more selected locations with the activated etchant material comprises: heating the surface of the cooling etchant material layer (140) and the sample (150) at one or more selected locations to activate the cooling etchant material, and performing anisotropic etching on the surface of the sample (150) at one or more selected locations with the activated etchant material.

18. The method (200) according to any one of claims 1 to 17, characterized in that, The method also includes measuring the etching depth in real time using an optical sensor device.

19. An apparatus (100) for etching a sample (150), characterized in that, The device (100) includes: A cooling device (110) is provided for cooling the surface of the sample (150), wherein the surface of the sample (150) is covered with an etchant material layer (140) and / or covered with the etchant material to form an etchant material layer (140) on the surface of the sample (150), and wherein the surface of the sample (150) and the etchant material layer (140) are cooled by the cooling device (110) to a cooling temperature below the activation temperature of the etchant material; Heating devices (120, 121) are used to heat the etchant material layer (140) and the surface of the sample (150) at one or more selected locations to activate the etchant material and etch the surface of the sample (150) at the one or more selected locations with the activated etchant material.

20. The apparatus (100) according to claim 19, characterized in that, The heating device (120, 121) includes a heating tip (121) for heating the surface of the etchant material layer (140) and the sample (150) by heat transfer at one or more selected locations.

21. The apparatus (100) according to claim 20, characterized in that, The device (100) includes a device (122) for scanning the heating tip (121) along the one or more selected locations.

22. The apparatus (100) according to claim 20 or 21, characterized in that, The device (100) also includes a sensor device for measuring the etching depth in real time using scanning probe microscopy.

23. The apparatus (100) according to any one of claims 20 to 22, characterized in that, The device (100) further includes a control unit (160) for controlling one or more of the following parameters: the distance from the surface of the etchant material layer (140) to the heating tip (121); the etching depth; and the heating duration; The temperature of the heating tip (121); the heating power for the heating tip (121); the scanning rate of the heating tip (121).

24. The apparatus (100) according to any one of claims 19 to 23, characterized in that, The heating device (120, 121) includes a laser (120) for heating the etchant material layer (140) and the surface of the sample (150) at one or more selected locations by laser radiation (120a) from the laser (120).

25. The apparatus (100) according to claim 24, characterized in that, The device (100) further includes an optical component (130) for directing the laser radiation (120a) from the laser (120) to one or more selected locations on the surface of the etchant material layer (140) and the sample (150).

26. The apparatus (100) according to claim 25, characterized in that, The optical component (130) is used to scan one or more selected locations on the surface of the etchant material layer (140) and the sample (150) with the laser radiation (120a) from the laser (120).

27. The apparatus (100) according to claim 25, characterized in that, The optical component (130) is used to project the laser radiation (120a) from the laser (120) through an etched pattern (125) onto one or more selected locations on the surface of the etchant material layer (140) and the sample (150).

28. The apparatus (100) according to any one of claims 24 to 27, characterized in that, The device (100) includes a control unit (160) for controlling one or more of the following: the power of the laser radiation (120a); the exposure time of the laser radiation (120a); the beam size of the laser radiation (120a); the beam shape of the laser radiation (120a); the pulse shape of the laser radiation (120a); the pulse repetition rate of the laser radiation (120a); and / or the power density of the laser radiation (120a).

29. The apparatus (100) according to any one of claims 19 to 28, characterized in that, The device (100) includes a control unit (160) for controlling the cooling temperature.

30. The apparatus (100) according to any one of claims 19 to 29, characterized in that, The cooling device (110) includes a cryostat (110) for cooling the surface of the sample (150) and the etchant material layer (140) to a cooling temperature below the activation temperature of the etchant material.

31. The apparatus (100) according to any one of claims 19 to 30, characterized in that, The sample (150) includes semiconductor sample material, metal sample material, alloy sample material, glass sample material and / or solid sample material.

32. The apparatus (100) according to any one of claims 19 to 31, characterized in that, The apparatus (100) includes a deposition apparatus for covering the surface of the sample (150) with the etchant material to form an etchant material layer (140) on the surface of the sample (150) by evaporating the etchant material and guiding the etchant material onto the surface of the sample (150) through a feedthrough (115).

33. The apparatus (100) according to any one of claims 19 to 32, characterized in that, The apparatus (100) includes a deposition apparatus for forming an etchant material layer (140) on the surface of the sample (150) by spraying the etchant material onto the surface of the sample (150).

34. The apparatus (100) according to any one of claims 19 to 33, characterized in that, The etchant material includes acidic etchant materials and / or alkaline etchant materials.

35. The apparatus (100) according to any one of claims 19 to 34, characterized in that, The heating devices (120, 121) are used to heat the etchant material layer (140) and the surface of the sample (150) at one or more selected locations to activate the etchant material and perform anisotropic etching on the surface of the sample (150) at one or more selected locations with the activated etchant material.

36. The apparatus (100) according to any one of claims 19 to 35, characterized in that, The device (100) further includes an optical sensor device for measuring the etching depth in real time.

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