Method for manufacturing mask plate by using deep silicon etching technology and method for preparing halide perovskite array pattern by using mask plate

Abstract

The invention discloses a method for manufacturing a mask plate by using a deep silicon etching technology. The method comprises the following steps of: a, pretreating a silicon substrate; b, coating photoresist on the silicon substrate pretreated in the step a, performing soft baking, standing, exposing, developing, fixing and post-baking, and forming a required pattern on the silicon substrate; and c, etching and cleaning the silicon substrate in the step b to obtain the mask plate. Meanwhile, the invention provides a method for preparing a perovskite array pattern by using the mask plate. According to the method, the perovskite array pattern is prepared by adopting dry etching, the perovskite is etched by utilizing a reactive ion beam process, the process is simple, reactive ion beam etching equipment is simple in structure, low in cost and compatible with all MEMS scale manufacturing factories, the manufacturing cost is reduced to a great extent, a new process strategy is provided for a perovskite array patterning scheme, and the method has a wide application prospect. The method reduces side corrosion, improves the patterning precision, and is suitable for micron-order pattern etching.

Description

Technical Field

[0001] The invention belongs to the technical field of perovskite array patterning, and specifically relates to a method for manufacturing a mask plate by using a deep silicon etching technology and a method for preparing a halide perovskite array pattern by using the mask plate. Background Art

[0002] Halide perovskite (hereinafter referred to as "perovskite") materials have the advantages of suitable band gap, high carrier mobility, high absorption coefficient, low exciton binding energy, long carrier lifetime, etc. Among them, quantum dots, nanowires and other structural materials based on perovskites have also become a new generation of optoelectronic functional materials, and have achieved rapid development in the fields of light-emitting diodes, solar cells, resistive memristors, etc. Therefore, they have also received extensive attention in the fields of communications, displays, photovoltaics, etc. The efficient, precise and large-scale construction of perovskite microstructure arrays on the substrate is an important prerequisite for the device application of perovskite materials.

[0003] At present, in the manufacture of MEMS devices, the array patterning production scheme is completed by using photolithography technology. For example, photolithography technology is first used to perform hydrophilic-hydrophobic patterning on a special substrate, such as a polyethylene terephthalate flexible substrate or a silicon-based substrate with silicon dioxide. The perovskite precursor solution can be only infiltrated in the hydrophilic area. After degradation and the formation of perovskite crystals, a perovskite patterned pattern is obtained. In the above-mentioned photolithography technology, the steps of coating, developing, and degumming require the use of a large amount of solution containing polar solvents, and polar solvents will corrode perovskites, so photolithography technology cannot be used to produce perovskite thin film array patterning.

[0004] In recent years, all the perovskite patterning schemes developed are hydrophilic-hydrophobic template methods, that is, after the substrate on which the perovskite is deposited is patterned, the perovskite is deposited and grown in the hydrophilic area to finally obtain a pattern. This scheme has many disadvantages, such as: 1. The types of perovskites are limited: There are many types of perovskites, and they are used for designated functional devices, such as light-emitting diodes, memristors, light sensors and other materials. Perovskites with specific photoelectric effects need to be selected as active materials, but in the perovskite family, there are films that are not suitable for the hydrophilic-hydrophobic template method. 2. There are irregularities at the edges of the pattern: When the resolution level of the perovskite array point pattern is tens of nanometers to several microns, the perovskite array points are not easy to control within the pattern, because the hydrophilic-hydrophobic template method is to limit the pattern to which the perovskite precursor liquid is attached, and then the perovskite continues to grow on the pattern. Usually, the perovskite grain size is tens to hundreds of microns, which can easily exceed the edge of the pattern, resulting in the problem that the edge and size of the perovskite film pattern cannot be completely consistent with the pattern. 3. High technical requirements: There are certain requirements for the substrate material. In order to realize the photolithography process of the hydrophilic-hydrophobic layer, the substrate generally needs to be covered with special coating materials (ITO, FTO, ZnO, TiO2). 4. Complex process: The hydrophilic-hydrophobic template method process requires the coating of a hydrophilic film and photoresist, and the use of photolithography technology, which leads to a complex overall process and very high technical requirements, which is not conducive to the large-scale development and manufacturing of MEMS electronic devices. Summary of the invention

[0005] The object of the present invention is to provide a method for manufacturing a mask plate using deep silicon etching technology. At the same time, providing a method for preparing a halide perovskite array pattern using a mask plate is another invention object of the present invention.

[0006] Based on the above purpose, the present invention adopts the following technical solutions: The method for manufacturing a mask plate using deep silicon etching technology comprises the following steps: a. Pretreatment of silicon substrate; b. coating photoresist on the silicon substrate pretreated in step a, soft-baking, standing, exposing, developing, fixing, and post-baking to form a desired pattern on the silicon substrate; c. Etch and clean the silicon substrate in step b to obtain a mask plate.

[0007] In step c, the etching adopts the Bosch etching process, which specifically includes a deposition-first etching-second etching cycle, and the deposition conditions are: the main RF gas is C4F8, the flow rate is 100-600 sccm; the secondary RF gas is C4F8, the flow rate is 50-200 sccm, the total chamber pressure is set to 10-60 mTorr, and the deposition time is 0.5-3 s; The first etching conditions are as follows: the lower electrode power is 50-90 W, the main RF gas is SF6, the flow rate is 100-600 sccm, the total chamber pressure is set to 10-60 mTorr, and the etching time is 0.5-3 s; The second etching conditions are as follows: the lower electrode power is 15-20 W, the main RF gas is SF6, the flow rate is 100-600 sccm, the total chamber pressure is set to 10-60 mTorr, and the etching time is 0.5-3 s.

[0008] In step c, the number of deposition-first etching-second etching cycles is 300-800 times, and the main RF incident power used in the Bosch etching process cycle is 1500-2400 W, and the secondary RF incident power is 200-800 W.

[0009] Step c, before etching, the silicon substrate is cleaned with oxygen plasma for 13-17s at a main RF incident power of 2200-2700 W, an O2 flow rate of 180-220 sccm, a chamber pressure of 22-28 mTorr, and a lower electrode power of 70-90 W.

[0010] In step b, a photoresist is coated on the silicon substrate pretreated in step a, and the photoresist is baked at a soft baking temperature of 90-110° C. for 8-12 min. After standing for 3-8 h, the photoresist is exposed and developed, and the photoresist is baked at a post-baking temperature of 110-130° C. for 12-18 min to form a desired pattern on the silicon substrate.

[0011] In step b, the photoresist is negative photoresist AZ4620, and the thickness of the photoresist on the silicon substrate is 7-9 μm. The exposure adopts a laser direct writing lithography system; when developing, the silicon substrate is immersed in S319 developer for 4-8 minutes, taken out, and rinsed with deionized water.

[0012] In step a, the silicon substrate is pretreated by using a cleaning solution to clean the silicon substrate under ultrasonic conditions and then drying it; the thickness of the silicon substrate is 50-100 µm. The silicon substrate is made of a double-polished silicon wafer, and the cleaning solution is acetone, deionized water, isopropyl alcohol or anhydrous ethanol.

[0013] Silicon substrate pretreatment method: Place the silicon substrate in acetone, deionized water, and isopropanol in turn, ultrasonically clean them for 5 minutes respectively, take out the silicon substrate, and blow dry it with a nitrogen gun.

[0014] The method for preparing a halide perovskite array pattern using the mask plate prepared by the above method is characterized by comprising the following steps: 1) Preparation of halide perovskite thin films; 2) Dry etching array pattern: A mask is covered on the halide perovskite film in step 1), and the pattern formed by the mask corresponds to the halide perovskite array pattern. After etching using reactive ion etching technology and inductively coupled plasma etching technology, respectively, the mask is removed to form a halide perovskite film array pattern.

[0015] In step 2), the mask plate includes a first mask plate and a second mask plate, and the pattern formed by the combination of the first mask plate and the second mask plate corresponds to the halide perovskite array pattern; the reactive ion etching technology adopts a reactive ion etching system, and the inductively coupled plasma etching technology adopts an inductively coupled plasma etching system.

[0016] In step 2), the etching method comprises the following steps: a. First, a first mask is covered on the halide perovskite film, and after being fixed in position, the film is placed in a reaction chamber of a reactive ion etching system, and after etching under vacuum conditions, the halide perovskite film and the first mask are taken out; b. Place the halide perovskite film and the first mask in the fast sample chamber of the inductively coupled plasma etching system under vacuum (the vacuum degree is 1.0e during the transfer process). -2 Pa), transfer the halide perovskite film and the first mask into the etching chamber, and the vacuum degree is 1.0 e -7 -1.0 e -9 Pa, etching is performed, and after etching is completed, the halide perovskite film and the first mask are transferred back to the fast sample injection chamber, taken out, and the first mask is removed; c. Cover the halide perovskite film with a second mask plate, fix it in place, and then place it in the reaction chamber of the reactive ion etching system and the etching chamber of the inductively coupled plasma etching system in turn for etching. After etching, the halide perovskite film and the second mask plate are transferred back to the fast sample injection chamber, taken out, and the second mask plate is removed.

[0017] In step 2), the etching conditions in step a are as follows: the reaction chamber is evacuated to 10 -5 Pa, the etching gas is a combination of CF4 and CHF3, the flow rate of CF4 is 20-40 sccm, the flow rate of CHF3 is 5-20 sccm, the gas pressure is 1-8 Pa, the plasma excitation RF power is 50-100 W, and the etching time is 5-10 min; Etching conditions in step b: upper electrode power is 200-800 W, lower electrode power is 20-80 W, etching gas is a combined atmosphere of chlorine and argon, gas pressure is 2-6 mTorr, chlorine flow rate is 10-15 sccm, argon flow rate is 7-10 sccm, etching time is 1-2 min.

[0018] There are many types of perovskite film materials, each with different photoelectric properties. In the dry etching method of the present invention, there is no restriction on the type, element, morphology and structure of the perovskite film. It is applicable to traditional perovskite films and also to perovskite films with modified element positions (A / B / X). The morphology of the perovskite film can be a crystal particle covering layer, a line or a mesh.

[0019] Perovskite thin film materials can be made of ABX3 type materials, where A can be NH4 + 、[(CH3)NH4] + 、[(CH2)3NH2] + 、[NH2(CH)NH2] + 、[(CH3)2NH2] + 、[(C2H5)NH3] + 、[C(NH2)3] + 、[(CH3)4N] + Single or multiple organic groups, or Cs + , Rb + , K + One or more metal ions; B is Pb 2+ Sn 2+ One or more heavy metal ions; X is a halide ion, Cl - Br - ,I - One or more of .

[0020] The method for preparing a perovskite film comprises the following steps: 1. Substrate / base cleaning; 2. Perovskite film deposition: one-step spin coating or two-step spin coating.

[0021] In step 1, the cleaning method is: first use a detergent prepared with deionized water (deionized water and detergent powder are conventionally prepared, and there is no special requirement for the ratio) to clean (ultrasonic cleaning method can be used) one or two times, rinse with deionized water and blow dry; then clean with acetone (ultrasonic cleaning method can be used), blow dry; then clean with alcohol (ultrasonic cleaning method can be used), blow dry; O2 or Ar plasma can be used to remove organic impurities on the surface of the substrate / base; the material of the substrate can be Si-based wafer, sapphire (Al2O3), ITO, glass, polyethylene, polyethylene terephthalate (PET) or polyimide (PI) and other materials.

[0022] The one-step spin coating method is to nucleate and grow the perovskite film in the precursor solution containing all the compounds of the perovskite. The specific method is as follows: 1) Prepare the perovskite precursor solution: mix the ABX3 compound with the solvent to prepare the precursor solution; 2) Spin coating: adsorb the cleaned substrate or substrate on a spin coater or a spin coater, cover the surface of the substrate or substrate with the perovskite precursor solution, pre-run at a speed of 300-500 rpm for 3-10 seconds, and then run at a speed of 2000-3000 rpm for 30-60 seconds; 3) Place the substrate or substrate with the spin-coated perovskite precursor solution on a hot plate at 100-180° for annealing to evaporate the solvent and crystallize to form a perovskite film.

[0023] Preparation of CH3NH3PbI3 thin film: 1) preparing perovskite precursor solution: mixing a certain amount of CH3NH3I and PbI2 in a molar ratio of 1:1 in an organic solvent, wherein the total molar concentration of CH3NH3I and PbI2 is 1-100 mol / mL; 2) Spin coating process can be used: adsorb the substrate or substrate on the spin coater or coater, cover the surface of the substrate or substrate with the perovskite precursor solution, pre-run at a speed of 300-500 rpm for 3-10 s, and then run at a speed of 2000-3000 rpm for 30-60 s; 3) Place the substrate or substrate on which the perovskite precursor solution is spin-coated on a heating plate at 100-180° for annealing to evaporate the solvent and crystallize to form a perovskite film. The organic solvent is one or a mixed solvent of two or more of N,N-dimethylformamide (DMF), gamma-butyrolactone (GBL), and dimethyl sulfoxide (DMSO).

[0024] The difference from the preparation of CH3NH3PbI3 film is that in the preparation of [(CH2)3NH2]PbI3 film, the perovskite precursor solution is prepared by preparing a mixed salt solution of [(CH2)3NH2]I and PbI2 of a certain concentration according to the proportion and molar mass, the molar ratio of [(CH2)3NH2]I and PbI2 is 1:1, and the total molar concentration of [(CH2)3NH2]I and PbI2 is 1-100 mol / L.

[0025] To prepare [CH3NH3]PbBr3 thin film, a mixed salt solution of [CH3NH3]Br and PbBr2 of a certain concentration is prepared according to the proportion and molar mass, the molar ratio of [CH3NH3]Br and PbBr2 is 1:1, and the total molar concentration is 1-100 mol / L.

[0026] To prepare [CH3NH3]SnI3 thin film, a mixed salt solution of [(CH2)3NH2]I and SnI2 of a certain concentration is prepared according to the proportion and molar mass, the molar ratio of [(CH2)3NH2]I and SnI2 is 1:1, and the total molar concentration is 1-100 mol / L.

[0027] Other similar to [(CH2)3NH2]PbBr 3-a-b I a Cl b The perovskite with mixed element components at the A, B or X positions can be prepared according to the above and so on, and the corresponding salt mixed solution can be prepared. The solvents used to prepare the precursor solution can be one or more mixed solvents of DMF, GBL and DMSO.

[0028] The two-step spin coating method is suitable for the case where the perovskite film material is two or more compounds. The specific method is to mix two or more compounds separately to form precursor solvents respectively, and then gradually deposit each precursor solution, and then perform heating annealing treatment to evaporate the solvent and crystallize to form a perovskite film.

[0029] The CH3NH3PbI3 thin film was prepared by a two-step method, and the specific method is as follows: 1) preparing the perovskite precursor solution separately, dissolving a certain amount of CH3NH3I salt in isopropyl alcohol (IPA) to prepare a solution with a concentration of 1-100 mol / mL, and dissolving PbI2 in DMF solvent to prepare a solution with a concentration of 1-100 mol / mL; 2) Step-by-step deposition, the PbI2 film layer can be deposited on the substrate or base by spin coating process, pre-running at a speed of 300-500 rpm for 3-10 s, then running at a speed of 2000-3000 rpm for 30-60 s, and then depositing CH3NH3I salt by immersion or spin coating, wherein the immersion method is to place the substrate or base in the salt solution for a few seconds, and the spin coating method is the same as the above method; 3) Place the substrate or substrate on a hot plate at 100-180° for annealing to evaporate the solvent and crystallize to form a perovskite film.

[0030] To prepare [(CH2)3NH2]PbI3 thin film, the perovskite precursor solution is prepared with [(CH2)3NH2]I and PbI2 salt solutions according to certain dosage and concentration. To prepare [CH3NH3]PbBr3 thin film, the perovskite precursor solution is prepared with [CH3NH3]Br and PbBr2 salt solutions according to certain dosage and concentration. To prepare [CH3NH3]SnI3 thin film, the precursor solution is prepared with [(CH2)3NH2]I and SnI2 salt solutions according to certain dosage and concentration. Other similar [(CH2)3NH2]PbBr 3-a-b I a Cl b The perovskite with mixed element components at the A, B or X positions can be prepared by analogy as above, and the corresponding two salt solutions can be prepared. The solvents used to prepare the precursor solution can be one or more mixed solvents of IPA, DMF, GBL and DMSO. Steps 2) and 3) refer to the above two-step method for preparing CH3NH3PbI3 thin film.

[0031] Compared with the prior art, the present invention has the following beneficial effects: 1) The present invention uses a deep silicon etching (Bosch) process to produce a silicon-based hollow plate as a dry etching mask tool for patterning perovskite arrays (ten micrometers and above); 2) Dry etching is used to prepare the perovskite display pattern, and the perovskite is etched using a reactive ion beam and inductively coupled process. The process is simple, the reactive ion beam etching equipment has a simple structure, the equipment is cheap, and it is compatible with all MEMS scale manufacturing plants, which greatly reduces the manufacturing cost and proposes a new process strategy for the perovskite array patterning solution, which reduces side corrosion and improves patterning accuracy. It is suitable for micron-level pattern etching. 3) It avoids the situation where perovskite is corroded by solvents and is not restricted by the type of perovskite. It is suitable for all types of perovskite thin film materials, such as glass with ITO, FTO, ZnO, TiO2 substrates or plastic substrates such as PET, which expands the compatibility of manufacturing various functional materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a SEM photo of the cross section of the halide perovskite film of Example 1; Figure 2 This is a cross-sectional SEM photograph of the halide perovskite array of Example 1; Figure 3 This is an optical photograph of a perovskite pattern with a line width of 100 microns in halide perovskite etching in Example 1; Figure 4 This is an optical photograph of a perovskite pattern with a line width of 100 microns etched using reactive ion beam etching technology in the comparative example of Example 4; Figure 5 This is a schematic structural diagram of the first mask plate of Example 1; Figure 6 This is a schematic structural diagram of the second mask plate of Example 1. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention is described in detail below, but the following embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by those skilled in the art without making creative work belong to the scope of protection of the present invention.

[0034] Example 1 The method of making a mask plate using deep silicon etching technology is to etch a 500 nm thick (Cs x (CH3NH2) y (CH3NH3) 1-x-y)Pb(I 1-z Br z )3 thin film array pattern, comprising the following steps: a. Pretreatment of silicon substrate: The thickness of the silicon substrate is 100 µm. The silicon substrate is made of double-polished silicon wafer. The silicon substrate is placed in acetone, deionized water, and isopropanol in sequence, and ultrasonically cleaned for 5 min respectively. The silicon substrate is taken out and blown dry with a nitrogen gun; b. coating photoresist on the silicon substrate pretreated in step a, soft-baking, standing, exposing, developing, fixing, and post-baking to form a desired pattern on the silicon substrate; In step b, a photoresist (negative photoresist AZ4620) is coated on the silicon substrate pretreated in step a, the thickness of the coated photoresist is 9 μm, and the substrate is baked at a soft baking temperature of 100°C for 10 min. After standing for 6 h, a laser direct writing lithography system is used for exposure, development and fixing. The silicon substrate is placed in an S319 developer for 6 min, taken out, rinsed with deionized water, and placed on a 120°C hot plate for post-baking for 15 min. c. Adhere the silicon substrate prepared in step b to the sample tray using high-temperature thermal conductive silicone oil, place the tray into the automatic injection chamber of the deep silicon etching system (SPTS Omega LPX rapier), set the sample stage temperature in the reaction chamber to 10 °C, set the back helium pressure to 15 Torr, use oxygen plasma to clean the silicon substrate for 15 s at the main RF incident power of 2400 W, the O2 flow rate of 200 sccm, the chamber pressure of 25 mTorr, and the lower electrode power of 78 W; Then, the silicon substrate in step b is etched using a Bosch etching process, specifically including a deposition-first etching-second etching cycle, with the number of cycles being 326 times. The main RF incident power used in the Bosch etching process cycle is 2200 W, and the secondary RF incident power is 500 W. Deposition conditions: the lower electrode power was set to 0 W, the main RF gas was C4F8 with a flow rate of 360 sccm; the secondary RF gas was C4F8 with a flow rate of 120 sccm, the total chamber pressure was set to 35 mTorr, and the deposition time was 1.4 s; The first etching conditions were as follows: the lower electrode power was 80 W, the main RF gas was SF6, the flow rate was 300 sccm, the total chamber pressure was set to 25 mTorr, and the etching time was 1.3 s; The second etching conditions were as follows: the lower electrode power was 17 W, the main RF gas was SF6, the flow rate was 400 sccm, the total chamber pressure was set to 35 mTorr, and the etching time was 1.5 s. After the Bosch process is completed, the silicon substrate is taken out and immersed in isopropyl alcohol (IPA) to clean the silicone oil at the bottom of the silicon substrate. It is blown dry with an N2 gun and then immersed in acetone to clean the residual photoresist on the surface of the silicon substrate. It is blown dry with an N2 gun to obtain a mask plate.

[0035] The perovskite array pattern takes an n=20 (columns) × m=20 (rows) array as an example. The dot matrix is ​​a square with a side length of a = b = 100 μm, and the row and column resolution is c = d = 100 μm.

[0036] The mask plate is divided into a first mask plate and a second mask plate, and a pattern formed by the combination of the first mask plate and the second mask plate corresponds to the halide perovskite array pattern.

[0037] 1. The structure formed by the first mask plate is a hollow grid-shaped horizontal stripe mask plate, such as Figure 5 As shown, the length and width of the transverse stripes are n*d and b respectively, the longitudinal spacing between the transverse stripes and the adjacent stripes is c, and there are m stripes in total, which can ensure that the size accuracy of the grating stripes is better than 1 μm.

[0038] 2. The structure formed by the second mask plate is a hollow grid-like vertical stripe mask plate, such as Figure 6 As shown, the length and width of the vertical stripes are m*c and a respectively, the lateral spacing between the vertical stripes and the adjacent stripes is d, and there are n stripes in total. The stripe size accuracy can be guaranteed to be better than 1 μm.

[0039] The method for preparing a halide perovskite array pattern using the mask plate prepared by the above method is characterized by comprising the following steps: 1) Preparation of halide perovskite film (select 500 nm thick (Cs x (CH3NH2) y (CH3NH3) 1-x-y )Pb(I 1- z Br z )3 Thin film, one-step method): a. Substrate cleaning: first use a detergent prepared with deionized water (prepared with deionized water and detergent powder at a mass ratio of 15:1) to ultrasonically clean twice, rinse with deionized water and blow dry; then use acetone to ultrasonically clean once, blow dry; then use alcohol to ultrasonically clean once, blow dry; O2 plasma can be used to remove organic impurities on the surface of the Si-based wafer substrate; b. Perovskite film deposition: (1) Preparation of perovskite precursor solution: a certain amount of CH3NH2I, CH3NH3Br, PbI2 and PbBr2 were mixed in a mixture of DMF and DMSO (DMF and DMSO were in equal volumes), CsI was dissolved in the DMF solution, and the molar concentration of each substance was prepared to be 1 mol / L. Then the above five solvent substances were mixed in an equimolar ratio; (2) Spin coating: The substrate is adsorbed on the spin coater, the perovskite precursor solution is covered on the substrate surface, and the spin coater is pre-run at a speed of 300 rpm for 5 s, and then run at a speed of 2000 rpm for 30 s; (3) Place the substrate with the spin-coated perovskite precursor solution on a hot plate at 100° for annealing to evaporate the solvent and crystallize to form a perovskite film. The SEM photo of the film cross section is shown in the figure. Figure 1 shown.

[0040] 2) Dry etching array pattern: a. First, on the halide perovskite film (Cs x (CH3NH2) y (CH3NH3) 1-x-y )Pb(I 1-z Br z )3) After covering the first mask plate and fixing it in position (using an optical microscope and a substrate transfer platform to calibrate the relative positions of the mask plate and the perovskite film, completing the alignment correction operation between the mask plate and the substrate (film and substrate), and fixing the mask plate and the perovskite film with a spring pressing device), place it in the reaction chamber of the reactive ion etching system (RIE), close the reaction chamber, and evacuate it to 10 -5 Pa, the etching gas is a combination of CF4 and CHF3, the flow rate of CF4 is 30 sccm, the flow rate of CHF3 is 10 sccm, the gas pressure is 2 Pa, the plasma excitation RF power is 80 W, and the etching is 6 min; take out the halide perovskite film and the first mask; The reaction formula is as follows: CH3NH2 + + e - → CH3NH2(g) reacts preferentially CH3NH2+e - → CHx (g) + NHx (g) Preferential reaction CH3NH3+e - → CHx(g) + NHx(g) + H + Priority Response Pb 2+ + F - → PbF2(g) Pb 2+ + F - → PbF2(s) is partially solid-phase deposited on the substrate Cs + + F - → CsF (g) Cs + + F -→ CsF (s) is partially solid-phase deposited on the substrate I - + H + → HI (g) b. Place the halide perovskite film and the first mask in the rapid sample chamber of the inductively coupled plasma etching system (ICP) under a vacuum environment (the vacuum degree is 1.0e during the transfer process). -2 Pa), transfer the halide perovskite film and the first mask into the etching chamber, and the vacuum degree is 1.0 e -7 Pa, etching was performed and the first mask was removed; etching conditions: the sample stage temperature was set to 30°C, the back He pressure was set to 10 Torr, the upper electrode power was 800 W, the lower electrode power was 50 W, the etching gas was a combined atmosphere of chlorine and argon, the gas pressure was 4 mTorr, the chlorine flow rate was 12 sccm, the argon flow rate was 9 sccm, and the etching time was 2 min; The reaction formula is as follows: Pb 2+ + Cl - → PbCl2(g) is very reactive Pb 2+ + F - → PbF2(g) Cs + + Cl - → CsCl (g) is reactive Cs + + F - → CsF (g) I - + H + → HI (g) CH3NH2 + + e - → CH3NH2(g) CH3NH3+e - → CH x (g) + NH x (g)+ H + c. Cover the halide perovskite film with a second mask plate, fix it in place, and then place it in the reaction chamber of the reactive ion etching system and the etching chamber of the inductively coupled plasma etching system in turn, and perform etching according to steps a and b (the process parameters in this step are the same as those in steps a and b). After etching, the halide perovskite film and the second mask plate are transferred back to the fast sample injection chamber, taken out, and the second mask plate can be removed.

[0041] The obtained cross-sectional SEM photos of the perovskite array are as follows: Figure 2As shown. Figure 3 shown.

[0042] Depend on Figure 2 It can be seen that the film is grown on silicon dioxide, with Si as the substrate. An array point is randomly selected, and SEM photos are taken at three positions of the array point. The SEM photos of the green frame area and the blue frame area are the edge positions of the array point, respectively. It can be seen that the edge structure of the perovskite film is clear, the area outside the array point is etched cleanly without residue, and the thickness of the array point is about 500 nm. From the SEM photo of the middle yellow frame area, the total thickness of the film cross section is about 500nm, indicating that after etching, the thickness of the array point is uniform from the edge to the center, there is no over-etching and thinning of the array point film, and there is no side etching at the edge. Figure 3 It can be seen that there is no side erosion on the side of the perovskite film pattern.

[0043] Example 2 The method for manufacturing a mask plate using deep silicon etching technology comprises the following steps: a. Pretreatment of silicon substrate: The thickness of the silicon substrate is 100 µm. The silicon substrate is made of double-polished silicon wafer. The silicon substrate is placed in acetone, deionized water, and isopropanol in sequence, and ultrasonically cleaned for 5 min respectively. The silicon substrate is taken out and blown dry with a nitrogen gun; b. coating photoresist on the silicon substrate pretreated in step a, soft-baking, standing, exposing, developing, fixing, and post-baking to form a desired pattern on the silicon substrate; In step b, a photoresist (negative photoresist AZ4620) is coated on the silicon substrate pretreated in step a, the thickness of the coated photoresist is 7 μm, and the substrate is baked at a soft baking temperature of 100°C for 10 min. After standing for 6 hours, a laser direct writing lithography system is used for exposure, development and fixing. The silicon substrate is immersed in S319 developer for 8 min, taken out, rinsed with deionized water, and baked at a post-baking temperature of 130°C for 12 min. c. Adhere the silicon substrate prepared in step b to the sample tray using high-temperature thermal conductive silicone oil, place the tray into the automatic sampling chamber of the deep silicon etching system (SPTS Omega LPX rapier), set the sample stage temperature in the reaction chamber to 10 °C, set the back helium pressure to 15 Torr, use oxygen plasma to clean the silicon substrate for 15 s at the main RF incident power of 2400 W, the O2 flow rate of 200 sccm, the chamber pressure of 25 mTorr, and the lower electrode power of 78 W; Then the silicon substrate in step b is etched using a Bosch etching process, specifically including a deposition-first etching-second etching cycle, the number of cycles is 300 times, the main RF incident power used in the Bosch etching process cycle is 1500 W, and the secondary RF incident power is 800 W; Deposition conditions: the lower electrode power was set to 0 W, the main RF gas was C4F8 with a flow rate of 550 sccm; the secondary RF gas was C4F8 with a flow rate of 200 sccm, the total chamber pressure was set to 50 mTorr, and the deposition time was 3 s; The first etching conditions were as follows: the lower electrode power was 90 W, the main RF gas was SF6 with a flow rate of 100 sccm, the total chamber pressure was set to 20 mTorr, and the etching time was 1 s. The second etching conditions were as follows: the lower electrode power was 15 W, the main RF gas was SF6 with a flow rate of 500 sccm, the total chamber pressure was set to 20 mTorr, and the etching time was 3 s. After the Bosch process is completed, the silicon substrate is taken out and soaked in isopropyl alcohol (IPA) to clean the silicone oil at the bottom of the silicon substrate, blown dry with an N2 gun, and then soaked in acetone to clean the photoresist remaining on the surface of the silicon substrate, blown dry with an N2 gun to obtain a mask plate. The mask plate includes a first mask plate and a second mask plate, and the pattern formed by the combination of the first mask plate and the second mask plate corresponds to the halide perovskite array pattern. The mask plate structure is the same as in Example 1.

[0044] The method for preparing a halide perovskite array pattern using the mask plate prepared by the above method comprises the following steps: 1) Preparation of halide perovskite film (select [CH3NH3]PbBr3 film, one-step method): a. Substrate cleaning: first use a detergent prepared with deionized water (prepared with deionized water and detergent powder at a mass ratio of 20:1) to ultrasonically clean twice, rinse with deionized water and blow dry; then use acetone to ultrasonically clean once, blow dry; then use alcohol to ultrasonically clean once, blow dry; use O2 plasma to remove organic impurities on the surface of the Si-based wafer substrate; b. Perovskite film deposition: (1) Preparation of perovskite precursor solution: Mix a certain amount of [CH3NH3]Br and PbBr2 in DMF at a molar ratio of 1:1, with a total molar concentration of 2 mol / L; (2) Spin coating: The substrate is adsorbed on the spin coater, the perovskite precursor solution is covered on the substrate surface, and the spin coater is pre-run at a speed of 400 rpm for 3 s, and then run at a speed of 3000 rpm for 40 s; (3) Place the substrate or wafer with the spin-coated perovskite precursor solution on a hot plate at 150° for annealing to evaporate the solvent and crystallize to form a perovskite film.

[0045] 2) Dry etching array pattern: a. First, cover the halide perovskite film ([CH3NH3]PbBr3 film) with the first mask, fix it in position (use an optical microscope and a substrate transfer platform to calibrate the relative positions of the mask and the perovskite film, complete the alignment correction operation of the mask and the substrate (film and substrate), and use a spring press device to fix the mask and the perovskite film), then place it in the reaction chamber of the reactive ion etching system (RIE), close the reaction chamber, and evacuate it to 10 -5 Pa, the etching gas is a combination of CF4 and CHF3, the flow rate of CF4 is 35 sccm, the flow rate of CHF3 is 7 sccm, the gas pressure is 3 Pa, the plasma excitation RF power is 100 W, and the etching is 10 min; take out the halide perovskite film and the first mask; The reaction formula is as follows: CH3NH2 + + e - → CH3NH2(g) reacts preferentially CH3NH2+e - → CHx (g) + NHx (g) Preferential reaction CH3NH3+e - → CHx(g) + NHx(g) + H + Priority Response Pb 2+ + F - → PbF2(g) Pb 2+ + F - → PbF2(s) is partially solid-phase deposited on the substrate b. Place the halide perovskite film and the first mask in the rapid sample chamber of the inductively coupled plasma etching system (ICP) under a vacuum environment (the vacuum degree is 1.0e during the transfer process). -2 Pa), transfer the halide perovskite film and the first mask into the etching chamber, and the vacuum degree is 1.0 e -9 Pa, etching was performed and the first mask was removed; etching conditions: the sample stage temperature was set to 30°C, the back He pressure was set to 10 Torr, the upper electrode power was 600 W, the lower electrode power was 45 W, the etching gas was a combined atmosphere of chlorine and argon, the gas pressure was 6 mTorr, the chlorine flow rate was 15 sccm, the argon flow rate was 10 sccm, and the etching time was 2 min; The reaction formula is as follows: Pb 2+ + Cl - → PbCl2(g) is very reactive Pb2+ + F - → PbF2(g) Cs + + Cl - → CsCl (g) is reactive Cs + + F - → CsF (g) I - + H + → HI (g) CH3NH2 + + e - → CH3NH2(g) CH3NH3+e - → CH x (g) + NH x (g)+ H + c. Cover the halide perovskite film with a second mask plate, fix it in place, and place it in the reaction chamber of the reactive ion etching system and the etching chamber of the inductively coupled plasma etching system respectively. Etch it according to steps a and b (the process parameters in this step are the same as those in steps a and b). After etching, the halide perovskite film and the second mask plate are transferred back to the fast sample chamber, taken out, and the second mask plate is removed. The perovskite pattern is as follows: Figure 3 shown.

[0046] Depend on Figure 3 It can be seen that the thin film pattern of the present invention is etched according to the mask pattern, and no side etching occurs on the side of the thin film pattern.

[0047] Example 3 The method for manufacturing a mask plate using deep silicon etching technology comprises the following steps: a. Pretreatment of silicon substrate: The thickness of the silicon substrate is 50 µm. The silicon substrate is made of double-polished silicon wafer. The silicon substrate is placed in acetone, deionized water, and isopropanol in sequence, and ultrasonically cleaned for 5 min respectively. The silicon substrate is taken out and blown dry with a nitrogen gun; b. coating photoresist on the silicon substrate pretreated in step a, soft-baking, standing, exposing, developing, fixing, and post-baking to form a desired pattern on the silicon substrate; In step b, a photoresist (negative photoresist AZ4620) is coated on the silicon substrate pretreated in step a, the thickness of the coated photoresist is 9 μm, and the substrate is baked at a soft baking temperature of 100°C for 10 min. After standing for 6 h, a laser direct writing lithography system is used for exposure, development and fixing. The silicon substrate is immersed in S319 developer for 4 min, taken out, rinsed with deionized water, and baked at a post-baking temperature of 110°C for 18 min. c. Adhere the silicon substrate prepared in step b to the sample tray using high-temperature thermal conductive silicone oil, place the tray into the automatic sampling chamber of the deep silicon etching system (SPTS Omega LPX rapier), set the sample stage temperature in the reaction chamber to 10 °C, set the helium pressure to 15 Torr, use oxygen plasma to clean the silicon substrate for 15 s at the main RF incident power of 2500 W, the O2 flow rate of 200 sccm, the chamber pressure of 25 mTorr, and the lower electrode power of 78 W; Then the silicon substrate in step b is etched using a Bosch etching process, specifically including a deposition-first etching-second etching cycle, the number of cycles is 450 times, the main RF incident power used in the Bosch etching process cycle is 2400 W, and the secondary RF incident power is 800 W; Deposition conditions: the lower electrode power was set to 0 W, the main RF gas was C4F8 with a flow rate of 550 sccm; the secondary RF gas was C4F8 with a flow rate of 100 sccm, the total chamber pressure was set to 55 mTorr, and the deposition time was 1.5 s; The first etching conditions were as follows: the lower electrode power was 90 W, the main RF gas was SF6, the flow rate was 330 sccm, the total chamber pressure was set to 60 mTorr, and the etching time was 2 s; The second etching conditions were as follows: the lower electrode power was 20 W, the main RF gas was SF6, the flow rate was 440 sccm, the total chamber pressure was set to 40 mTorr, and the etching time was 3 s. After the Bosch process is completed, the silicon substrate is taken out and soaked in isopropyl alcohol (IPA) to clean the silicone oil at the bottom of the silicon substrate, blown dry with an N2 gun, and then soaked in acetone to clean the photoresist remaining on the surface of the silicon substrate, and blown dry with an N2 gun to obtain a mask plate. The mask plate structure is the same as in Example 1.

[0048] The method for preparing a halide perovskite array pattern using the mask plate prepared by the above method is characterized by comprising the following steps: Preparation of halide perovskite film ([C2H5NH3]PbI3), one-step method): a. Substrate cleaning: first use a detergent prepared with deionized water (prepared with deionized water and detergent powder at a mass ratio of 25:1) to ultrasonically clean twice, rinse with deionized water and blow dry; then use acetone to ultrasonically clean once, blow dry; then use alcohol to ultrasonically clean once, blow dry; Ar plasma can be used to remove organic impurities on the surface of the Si-based wafer substrate; b. Perovskite film deposition: (1) Preparation of perovskite precursor solution: Mix a certain amount of C2H5NH3I and PbI2 in DMF solvent, with each substance prepared to a molar concentration of 5 mol / L, and then mix the above two solvent substances in equal proportions; (2) Spin coating: The substrate is adsorbed on the spin coater, the perovskite precursor solution is covered on the substrate surface, and the spin coater is pre-run at a speed of 300 rpm for 5 s, and then run at a speed of 5000 rpm for 30 s; (3) Place the substrate with the spin-coated perovskite precursor solution on a hot plate at 100° for annealing to evaporate the solvent and crystallize to form a perovskite film.

[0049] 2) Dry etching array pattern: a. First, cover the halide perovskite film ([C2H5NH3]PbI3 film) with the first mask, fix it in position (use an optical microscope and a substrate transfer platform to calibrate the relative position of the mask and the perovskite film, complete the alignment correction operation of the mask and the substrate (film and substrate), and use a spring press device to fix the mask and the perovskite film), then place it in the reaction chamber of the reactive ion etching system (RIE), close the reaction chamber, and evacuate it to 10 -5 Pa, the etching gas is a combination of CF4 and CHF3, the flow rate of CF4 is 40 sccm, the flow rate of CHF3 is 5 sccm, the gas pressure is 8 Pa, the plasma excitation RF power is 100 W, and the etching is 5 min; the halide perovskite film and the first mask are taken out; The reaction formula is as follows: C2H5NH3 + + e - → C2H5NH3(g) preferentially reacts C2H5NH3 + + e - → CH x (g) + NH x (g) Priority response C2H5NH3+e - → CH x (g) + NH x (g)+ H + Priority Response Pb 2+ + F - → PbF2(g) Pb 2+ + F - → PbF2(s) is partially solid-phase deposited on the substrate I - + H + → HI (g) b. Place the halide perovskite film and the first mask in the rapid sample chamber of the inductively coupled plasma etching system (ICP) under a vacuum environment (the vacuum degree is 1.0e during the transfer process). -2Pa), transfer the halide perovskite film and the first mask into the etching chamber, and the vacuum degree is 1.0 e -9 Pa, etching was performed and the first mask was removed; etching conditions: the sample stage temperature was set to 30°C, the back He pressure was set to 10 Torr, the upper electrode power was 600 W, the lower electrode power was 45 W, the etching gas was a combined atmosphere of chlorine and argon, the gas pressure was 6 mTorr, the chlorine flow rate was 15 sccm, the argon flow rate was 10 sccm, and the etching time was 2 min; The reaction formula is as follows: Pb 2+ + Cl - → PbCl2(g) is very reactive Pb 2+ + F - → PbF2(g) I - + H + → HI (g) C2H5NH2 + + e - → CH3NH2(g) C2H5NH3+e - → CH x (g) + NH x (g)+ H + c. Cover the halide perovskite film with a second mask plate, fix it in position, and place it in the reaction chamber of the reactive ion etching system and the etching chamber of the inductively coupled plasma etching system respectively, and perform etching according to steps a and b (the process parameters in this step are the same as those in steps a and b). After etching, the halide perovskite film and the second mask plate are transferred back to the fast sample injection chamber, taken out, and the second mask plate is removed.

[0050] RIE was used for the first time, and plasma excited the CF4 and CHF3 gas combination, and the main active ion excited was F - , because the perovskite film components are composed of C, H, N, Pb, the main components of the A position include C, H, N. Among them, Pb is easy to react with F - The ions combine to form PbF2, but the molecular weight is large, so a certain amount of it will be deposited on the substrate in the solid phase, and it is difficult to be re-excited to the gas phase and leave the substrate. Therefore, when using RIE to etch a thicker perovskite film for the first time, the reaction byproducts will be deposited on the substrate surface in the etched area.

[0051] In order to improve the process quality, ICP can be used again to etch away the byproducts deposited on the substrate. The atmosphere used in the ICP process is a combination of Cl2 and Ar. Due to the effect of the lower electrode under the sample plate in the reaction chamber, ion traction perpendicular to the sample direction can be formed inside the reaction chamber. The solid phase PbCl2 deposited on the surface of the substrate is bombarded by electrons or Ar ions to form free Pb 2+ ions, and the Cl excited in the reaction chamber - Reaction to generate gaseous PbCl2, which is simultaneously discharged from the reaction chamber.

[0052] Example 4 Comparative Experiment Comparative Example: The difference from Example 1 is that in the method for preparing a halide perovskite array pattern using the mask plate prepared by the above method, step 2) dry etching the array pattern: only reactive ion etching is used, etching for 8 min, and the obtained perovskite pattern is as follows Figure 4 shown.

[0053] Depend on Figure 4 It can be seen that in the comparative example, only reactive ion beam etching is used. After etching cleanly, there is side corrosion at the edge of the pattern (10-30 µm). The reason is that only reactive ion beam etching is used. For organic element ions at position A, etching is fast, but for elements with relatively large mass such as Pb ions at position B or Cs at position A, the film thickness is large, or the pattern is small (within 100 µm) (the mask gap is small, and etching will be slow). In order to etch cleanly, the etching time can only be extended, but a long etching time will lead to side corrosion. For high-precision patterns (within 100 µm of side length), side corrosion will have a great impact on the size. Therefore, when reactive ion beam etching reaches a certain extent, that is, when side corrosion has not occurred, it is replaced with inductive coupling etching. Cl ions in inductive coupling are extremely effective in etching Pb, and because the lower electrode is added during the etching process, it has a vertical downward guiding effect on the active reactive ions, which can make the remaining Pb quickly etched away without side corrosion.

Claims

1. A method for manufacturing a mask plate using deep silicon etching technology, characterized in that: The following steps are involved: a. Pretreatment of silicon substrate; b. coating photoresist on the silicon substrate pretreated in step a, soft-baking, standing, exposing, developing, and post-baking to form a desired pattern on the silicon substrate; c. Etch and clean the silicon substrate in step b to obtain a mask plate.

2. The method for manufacturing a mask plate using deep silicon etching technology according to claim 1, characterized in that: In step c, the etching adopts the Bosch etching process, which specifically includes a deposition-first etching-second etching cycle, and the deposition conditions are: the main RF gas is C4F8, the flow rate is 100-600 sccm; the secondary RF gas is C4F8, the flow rate is 50-200 sccm, the total pressure of the chamber is set to 10-60 mTorr, and the deposition time is 0.5-3 s; The first etching conditions are as follows: the lower electrode power is 50-90 W, the main RF gas is SF6, the flow rate is 100-600 sccm, the total chamber pressure is set to 10-60 mTorr, and the etching time is 0.5-3 s; The second etching conditions are as follows: the lower electrode power is 15-20 W, the main RF gas is SF6, the flow rate is 100-600 sccm, the total chamber pressure is set to 10-60 mTorr, and the etching time is 0.5-3 s.

3. The method for manufacturing a mask plate using deep silicon etching technology according to claim 2, characterized in that: In step c, the number of deposition-first etching-second etching cycles is 300-800 times, and the main RF incident power used in the Bosch etching process cycle is 1500-2400 W, and the secondary RF incident power is 200-800 W.

4. The method for manufacturing a mask plate using deep silicon etching technology according to claim 3, characterized in that: In step b, a photoresist is coated on the silicon substrate pretreated in step a, and the photoresist is baked at a soft baking temperature of 90-110° C. for 8-12 min. After standing for 3-8 hours, the photoresist is exposed, developed, and fixed, and the photoresist is baked at a post-baking temperature of 110-130° C. for 12-18 min to form a desired pattern on the silicon substrate.

5. The method for manufacturing a mask plate using deep silicon etching technology according to claim 4, characterized in that: In step a, the silicon substrate is pretreated by using a cleaning solution to clean the silicon substrate under ultrasonic conditions and then drying the silicon substrate; the thickness of the silicon substrate is 50-100 µm.

6. A method for preparing a halide perovskite array pattern using a mask plate prepared by the method according to any one of claims 1 to 5, characterized in that: The following steps are involved: 1) Preparation of halide perovskite thin films; 2) Dry etching array pattern: A mask is covered on the halide perovskite film in step 1), and the pattern formed by the mask corresponds to the halide perovskite array pattern. After etching using reactive ion etching technology and inductively coupled plasma etching technology, respectively, the mask is removed to form a halide perovskite film array pattern.

7. The method for preparing a halide perovskite array pattern using a mask plate according to claim 6, characterized in that: In step 2), the mask plate includes a first mask plate and a second mask plate, and the pattern formed by the combination of the first mask plate and the second mask plate corresponds to the halide perovskite array pattern; the reactive ion etching technology adopts a reactive ion etching system, and the inductively coupled plasma etching technology adopts an inductively coupled plasma etching system.

8. The method for preparing a halide perovskite array pattern using a mask plate according to claim 7, characterized in that: In step 2), the etching method comprises the following steps: a. First, a first mask is covered on the halide perovskite film, and after being fixed in position, the film is placed in a reaction chamber of a reactive ion etching system, and after etching under vacuum conditions, the halide perovskite film and the first mask are taken out; b. placing the halide perovskite film and the first mask plate in a fast sample introduction chamber of an inductively coupled plasma etching system, and transferring the halide perovskite film and the first mask plate to the etching chamber under a vacuum environment for etching. After etching, the halide perovskite film and the first mask plate are transferred back to the fast sample introduction chamber, taken out, and the first mask plate is removed; c. Cover the halide perovskite film with a second mask plate, fix it in place, and then place it in the reaction chamber of the reactive ion etching system and the etching chamber of the inductively coupled plasma etching system in turn for etching. After etching, the halide perovskite film and the second mask plate are transferred back to the fast sample injection chamber, taken out, and the second mask plate is removed.

9. The method for preparing a halide perovskite array pattern using a mask plate according to claim 8, characterized in that: In step 2), the etching conditions of step a are as follows: the etching gas is a combined atmosphere of CF4 and CHF3, the flow rate of CF4 is 20-40 sccm, the flow rate of CHF3 is 5-20 sccm, the gas pressure is 1-8 Pa, the plasma excitation RF power is 50-100 W, and the etching time is 5-10 min; Etching conditions in step b: upper electrode power is 200-800 W, lower electrode power is 20-80 W, etching gas is a combined atmosphere of chlorine and argon, gas pressure is 2-6 mTorr, chlorine flow rate is 10-15 sccm, argon flow rate is 7-10 sccm, etching time is 1-2 min.

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