Method for area-selectively forming thin films and method for manufacturing memory device

Abstract

According to an embodiment of the present invention, a method for area-selectively forming thin films comprises: a step of providing a substrate on which oxide films and nitride films are alternately stacked; an inhibition film forming step of selectively forming inhibition films on the nitride films; a selective oxide film forming step of selectively forming selective oxide films on the oxide films; and an inhibition film etching step of removing the inhibition films.

Description

Method for forming a region-selective thin film and method for manufacturing a memory device including the same

[0001] The present invention relates to a method for forming a region-selective thin film and a method for manufacturing a memory device including the same, and more specifically, to a thin film processing method including a step of forming and etching a suppressor film and a method for manufacturing a memory device including the same.

[0002] As the miniaturization of NAND flash devices accelerates, they have evolved from the existing planar structure to a cylindrical structure, and from the cylindrical structure to a 3D structure with stacked layers.

[0003]

[0004] 3D NAND Flash is a structure in which cells are stacked vertically to overcome the scaling limitations of 2D NAND Flash. 3D NAND Flash increases integration density by increasing the number of stacked insulating and charge storage layers. It is relatively free in terms of space scaling because it can secure sufficient storage capacity with the charge storage layer while ensuring cell-to-cell space depending on the thickness of the insulating layer.

[0005]

[0006] However, due to extreme scaling, device manufacturing technology requires more sophisticated deposition and patterning techniques. Current 3D NAND Flash utilizes a structure where "Trap-continuous" charge trap layers are interconnected, resulting in charge loss occurring in the horizontal direction through these connected layers. While "Trap-cut" structures, in which the storage layers between cells are separated, are attracting attention as a method to improve this, there are difficulties in realizing the complete area-selective thin film formation (AS-ALD) required for manufacturing them. There is a limitation where thin films remain on unwanted surfaces even after repeated deposition and etching, and advanced process technology is required to achieve uniform deposition and etching characteristics across all cells in ultra-high stacking.

[0007]

[0008] Furthermore, conventional etching methods using fluorine and strong acids require overall improvement because the high etching speeds lead to reduced precision, damage to the film, and degradation of device characteristics due to residual impurities.

[0009] The objective of the present invention is to provide a method for forming a completely region-selective thin film and a method for manufacturing a memory device including the same.

[0010] Another objective of the present invention is to provide a region-selective thin film formation method capable of forming a uniform thin film through an atomic layer deposition and etching process, and a method for manufacturing a memory device including the same.

[0011] Another objective of the present invention is to provide a region-selective thin film formation method capable of maintaining thin film characteristics without leaving impurities, and a method for manufacturing a memory device including the same.

[0012] Other objects of the present invention will become more apparent from the following detailed description.

[0013] According to one embodiment of the present invention, a region-selective thin film forming method comprises: providing a substrate having oxide films and nitride films alternately stacked on the substrate; a suppression film forming step of selectively forming a suppression film on the nitride film; a selective oxide film forming step of selectively forming a selective oxide film on the oxide film; and a suppression film etching step of removing the suppression film.

[0014] The above oxide film may include silicon.

[0015] The above nitride film may be a silicon nitride film or a silicon oxynitride film.

[0016] The above inhibition film formation step may include a surface treatment agent supply step of supplying a surface treatment agent into the interior of a chamber on which the substrate is placed; a surface treatment agent purging step of purging the interior of the chamber; a step of supplying a first precursor into the interior of the chamber to selectively adsorb it onto the nitride film; and a first precursor purging step of purging the interior of the chamber.

[0017] The above inhibition film formation step may further include a reaction material supply step for supplying a reaction material inside the chamber after the first precursor purge step.

[0018] The above surface treatment agent supply step and the above surface treatment agent purging step, the above first precursor adsorption step and the above first precursor purging step can each be repeated two or more times.

[0019] The above surface treatment agent may contain the element chlorine.

[0020] The above surface treatment agent can be represented by the following <Chemical Formula 1>.

[0021] <Chemical Formula 1>

[0022]

[0023] In the above <Chemical Formula 1>,

[0024] X1 and X2 may each be the same or different from each other and are independently selected from hydrogen, a chlorine element, and a chloroalkyl group having 1 to 5 carbon atoms, and

[0025] R1 and R2 may each be the same or different from each other and are independently selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxyl group having 0 to 4 carbon atoms, and an alkoxy group having 0 to 4 carbon atoms.

[0026] The above surface treatment agent can be represented by the following <Chemical Formula 2>.

[0027] <Chemical Formula 2>

[0028]

[0029] In the above <Chemical Formula 2>,

[0030] n is independently selected from integers 1 to 4, and

[0031] R may be the same or different from each other and is selected from hydrogen atoms, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, and substituted alkyl cyclopentadienyl groups.

[0032] The above inhibitory film may be a metal-containing film having one of a trivalent metal, a tetravalent metal, or a pentavalent metal as a central element.

[0033] The above first precursor can be represented by the following <Chemical Formula 3>.

[0034] <Chemical Formula 3>

[0035]

[0036] In the above <Chemical Formula 3>, n is selected from integers 1 to 3, M0 is selected from trivalent metal elements including Al, Ga, and In, and L0 and X0 may be the same or different from each other and are independently selected from hydrogen atoms, alkyl groups having 1 to 6 carbon atoms, dialkylamines, cycloamine groups, alkoxy groups, or halogen elements.

[0037] The above first precursor can be represented by the following <Chemical Formula 4>.

[0038] <Chemical Formula 4>

[0039]

[0040] In the above <Chemical Formula 4>, n is selected from integers 1 to 4, and

[0041] M1 is selected from tetravalent metal elements including Ti, Hf, and Zr, X1 is selected from halogen elements, and L1 may be the same or different from each other and is selected from hydrogen atoms, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, substituted alkyl cyclopentadienyl groups, alkoxy groups having 1 to 5 carbon atoms, alkylamino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, alkylimido groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, and aralkyl groups having 7 to 13 carbon atoms.

[0042] The above first precursor can be represented by the following <Chemical Formula 5>.

[0043] <Chemical Formula 5>

[0044]

[0045] In the above <Chemical Formula 5>, n is selected from integers 1 to 5, and

[0046] M2 is selected from pentavalent metal elements including V, Nb, and Ta, X2 is selected from halogen elements, and L2 may be the same or different from each other and is selected from hydrogen atoms, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, substituted alkyl cyclopentadienyl groups, alkoxy groups having 1 to 5 carbon atoms, alkylamino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, alkylimido groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, and aralkyl groups having 7 to 13 carbon atoms.

[0047] The selective oxide film formation step may include the step of supplying a selectivity agent to the interior of the chamber; the step of purging the interior of the chamber; the step of supplying a second precursor to the interior of the chamber; the step of purging the interior of the chamber; and the step of supplying a reaction material to the interior of the chamber to react with the silicon precursor and form the selective oxide film.

[0048] The above selectivity agent can be represented by the following <Chemical Formula 6>.

[0049] <Chemical Formula 6>

[0050]

[0051] In the above <Chemical Formula 6>, n is each independently selected from integers from 0 to 5, X1 to X3 are each independently selected from an alkoxy group having 1 to 5 carbon atoms and a dialkylamine group having 1 to 5 carbon atoms, and R is selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and a dialkylamine group having 1 to 5 carbon atoms.

[0052] The above second precursor can be represented by the following <Chemical Formula 7>.

[0053] <Chemical Formula 7>

[0054]

[0055] In the above <Chemical Formula 7>,

[0056] L may be the same or different from each other and is selected from hydrogen atoms, halogen elements, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, substituted alkyl cyclopentadienyl groups, alkoxy groups having 1 to 5 carbon atoms, alkylamino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, alkylimido groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, and aralkyl groups having 7 to 13 carbon atoms.

[0057] The above inhibitor film etching step may include: a step of supplying an etching initiator to the interior of the chamber; a step of purging the interior of the chamber; a step of supplying a reaction material to the interior of the chamber; and a step of purging the interior of the chamber.

[0058] The above etching initiator can be represented by the following <Chemical Formula 8>.

[0059] <Chemical Formula 8>

[0060]

[0061] In the above <Chemical Formula 8>, n is each independently selected from integers from 0 to 5, X1 to X3 are each independently selected from an alkoxy group having 1 to 5 carbon atoms and a dialkylamine group having 1 to 5 carbon atoms, and R is selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and a dialkylamine group having 1 to 5 carbon atoms.

[0062] The above etching initiator can be represented by the following <Chemical Formula 9>.

[0063] <Chemical Formula 9>

[0064]

[0065] In the above <Chemical Formula 9>,

[0066] X1 and X2 may each be the same or different from each other and are independently selected from hydrogen, a chlorine element, and a chloroalkyl group having 1 to 5 carbon atoms, and

[0067] R1 and R2 may each be the same or different from each other and are independently selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxyl group having 0 to 4 carbon atoms, and an alkoxy group having 0 to 4 carbon atoms.

[0068] The above inhibition film and the above selective oxide film can be formed by atomic layer deposition (ALD).

[0069] The above inhibitor film can be removed by atomic layer etching (ALE).

[0070] The above method may further include a inhibition film etching step for removing an inhibition film formed on the oxide films between the inhibition film forming step and the selective oxide film forming step.

[0071] The above inhibition film formation step comprises: a surface treatment agent supply step of supplying a surface treatment agent into the interior of a chamber on which the substrate is placed; a surface treatment agent purging step of purging the interior of the chamber; a step of supplying a first precursor into the interior of the chamber to selectively adsorb it onto the nitride film; and a first precursor purging step of purging the interior of the chamber, wherein the surface treatment agent may be supplied selectively.

[0072] According to an embodiment of the present invention, a method for manufacturing a memory device may include the thin film formation method described above.

[0073] According to one embodiment of the present invention, complete region-selective thin film formation is possible, and a silicon oxide film can be selectively formed only on the oxide film.

[0074] In addition, it is possible to form region-selective thin films free of impurities, and to suppress the diffusion of charges trapped in the charge storage film in memory devices in vertical and horizontal directions.

[0075] In addition, charge retention characteristics in memory devices can be improved.

[0076] FIG. 1 is a diagram schematically illustrating a thin film formation process according to an embodiment of the present invention.

[0077] FIG. 2 is a graph schematically showing the supply cycle according to an embodiment of the present invention.

[0078] FIG. 3 is a graph schematically showing a supply cycle according to another embodiment of the present invention.

[0079] Figure 4 is a graph showing the Nb content of a substrate according to a comparative example and an embodiment of the present invention.

[0080] Figure 5 is a graph showing the result of selectively depositing a silicon precursor through a selectivity agent according to an embodiment of the present invention.

[0081] Figure 6 is a graph showing the result of selectively etching a metal oxide film using an etching initiator according to an embodiment of the present invention.

[0082] FIG. 7 is a diagram schematically illustrating a thin film formation process according to another embodiment of the present invention.

[0083] FIG. 8 is a graph schematically showing a supply cycle according to another embodiment of the present invention.

[0084] FIG. 9 is a graph schematically showing a supply cycle according to another embodiment of the present invention.

[0085] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the attached FIGS. 1 through 9. Embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be interpreted as being limited to the embodiments described below. These embodiments are provided to further explain the present invention in detail to those skilled in the art to which the invention pertains. Accordingly, the shape of each element shown in the drawings may be exaggerated to emphasize a clearer explanation.

[0086]

[0087] FIG. 1 is a diagram schematically illustrating a thin film formation process according to an embodiment of the present invention. FIG. 2 is a graph schematically illustrating a supply cycle according to an embodiment of the present invention, and FIG. 3 is a graph schematically illustrating a supply cycle according to another embodiment of the present invention.

[0088]

[0089] The substrate is loaded into the interior of the process chamber, and the following process conditions are adjusted. The substrate may be one of a material having semiconductor properties, an insulating material, a semiconductor covered by an insulating material, or a conductor. As illustrated in FIG. 1, the substrate has alternately stacked silicon oxide films and silicon nitride films (or silicon oxynitride films), and the oxide films and nitride films alternately stacked on the substrate may include structures formed in a vertical and horizontal direction on the upper surface of the substrate.

[0090]

[0091] Process conditions may include the temperature of the substrate or process chamber, chamber pressure, and gas flow rate. The substrate is exposed to a surface treatment agent supplied inside the chamber, and the surface treatment agent is adsorbed onto the substrate.

[0092]

[0093] Meanwhile, as illustrated in FIGS. 2 and 3, the first precursor can be adsorbed onto the substrate to form an inhibitory film, and the supply of the reaction material can be omitted. Additionally, when the surface treatment agent supply step and the purge step are considered as one subcycle (x) and the first precursor supply step and the purge step are considered as one subcycle (y), each subcycle can be repeated two or more times, and the number of repetitions may differ from each other. Similarly, when the reaction material supply step and the purge step are considered as one subcycle (z), the subcycle can be repeated, and the number of repetitions may differ from other subcycles (x,y).

[0094]

[0095] Specifically, the surface treatment agent can be represented by the following <Chemical Formula 1>.

[0096] <Chemical Formula 1>

[0097]

[0098] In the above <Chemical Formula 1>,

[0099] X1 and X2 may each be the same or different from each other and are independently selected from hydrogen, a chlorine element, and a chloroalkyl group having 1 to 5 carbon atoms, and

[0100] R1 and R2 may each be the same or different from each other and are independently selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxyl group having 0 to 4 carbon atoms, and an alkoxy group having 0 to 4 carbon atoms.

[0101]

[0102] In addition, the surface treatment agent can be represented by the following <Chemical Formula 2>.

[0103] <Chemical Formula 2>

[0104]

[0105] In the above <Chemical Formula 2>,

[0106] n is independently selected from integers 1 to 4, and

[0107] R may be the same or different from each other and is selected from hydrogen atoms, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, and substituted alkyl cyclopentadienyl groups.

[0108]

[0109] In addition, the surface treatment agent may contain the element chlorine.

[0110]

[0111] Subsequently, a purge gas (e.g., an inert gas such as Ar) is supplied to the inside of the chamber to remove or purify unadsorbed surface treatment agents or byproducts.

[0112]

[0113] Subsequently, the substrate is exposed to a first precursor supplied to the inside of the chamber, and the first precursor is adsorbed onto the substrate.

[0114]

[0115] Specifically, the first precursor can be represented by the following <Chemical Formula 3>.

[0116] <Chemical Formula 3>

[0117]

[0118] In the above <Chemical Formula 3>, n is selected from integers 1 to 3, M0 is selected from trivalent metal elements including Al, Ga, and In, and L0 and X0 may be the same or different from each other and are independently selected from hydrogen atoms, alkyl groups having 1 to 6 carbon atoms, dialkylamines, cycloamine groups, alkoxy groups, or halogen elements.

[0119]

[0120] In addition, the first precursor can be represented by the following <Chemical Formula 4>.

[0121] <Chemical Formula 4>

[0122]

[0123] In the above <Chemical Formula 4>, n is selected from integers 1 to 4, and

[0124] M1 is selected from tetravalent metal elements including Ti, Hf, and Zr, X1 is selected from halogen elements, and L1 may be the same or different from each other and is selected from hydrogen atoms, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, substituted alkyl cyclopentadienyl groups, alkoxy groups having 1 to 5 carbon atoms, alkylamino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, alkylimido groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, and aralkyl groups having 7 to 13 carbon atoms.

[0125]

[0126] In addition, the first precursor can be represented by the following <Chemical Formula 5>.

[0127] <Chemical Formula 5>

[0128]

[0129] In the above <Chemical Formula 5>, n is selected from integers 1 to 5, and

[0130] M2 is selected from pentavalent metal elements including V, Nb, and Ta, X2 is selected from halogen elements, and L2 may be the same or different from each other and is selected from hydrogen atoms, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, substituted alkyl cyclopentadienyl groups, alkoxy groups having 1 to 5 carbon atoms, alkylamino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, alkylimido groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, and aralkyl groups having 7 to 13 carbon atoms.

[0131]

[0132] Subsequently, a purge gas (e.g., an inert gas such as Ar) is supplied to the inside of the chamber to remove or purify unadsorbed precursors or byproducts.

[0133]

[0134] Subsequently, the substrate is exposed to a reaction material supplied to the inside of the chamber, and the reaction material reacts with the first precursor to form an inhibitory film. At this time, the reaction material may be any one of O3, O2, H2O, H2O2, N2O, or NH3. In addition, the inhibitory film may be a metal-containing film having one of a trivalent metal, a tetravalent metal, or a pentavalent metal as a central element.

[0135]

[0136] Subsequently, a purge gas (e.g., an inert gas such as Ar) is supplied to the inside of the chamber to remove or purify residual reaction materials or byproducts.

[0137]

[0138] Subsequently, the substrate is exposed to a selectivity agent supplied inside the chamber, and the selectivity agent is adsorbed onto the substrate.

[0139]

[0140] Specifically, the selectivity agent can be represented by the following <Chemical Formula 6>.

[0141] <Chemical Formula 6>

[0142]

[0143] In the above <Chemical Formula 6>, n is each independently selected from integers from 0 to 5, X1 to X3 are each independently selected from an alkoxy group having 1 to 5 carbon atoms and a dialkylamine group having 1 to 5 carbon atoms, and R is selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and a dialkylamine group having 1 to 5 carbon atoms.

[0144]

[0145] Subsequently, a purge gas (e.g., an inert gas such as Ar) is supplied to the inside of the chamber to remove or purify unadsorbed selectivity imparters or byproducts.

[0146]

[0147] Subsequently, the substrate is exposed to a second precursor supplied inside the chamber, and the second precursor is adsorbed onto the substrate. Specifically, the second precursor can be represented by the following <Chemical Formula 7>.

[0148] <Chemical Formula 7>

[0149]

[0150] In the above <Chemical Formula 7>,

[0151] L may be the same or different from each other and is selected from hydrogen atoms, halogen elements, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, substituted alkyl cyclopentadienyl groups, alkoxy groups having 1 to 5 carbon atoms, alkylamino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, alkylimido groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, and aralkyl groups having 7 to 13 carbon atoms.

[0152]

[0153] Subsequently, a purge gas (e.g., an inert gas such as Ar) is supplied to the inside of the chamber to remove or purify unadsorbed precursors or byproducts.

[0154]

[0155] Subsequently, the substrate is exposed to a reaction material supplied to the inside of the chamber, and the reaction material reacts with the second precursor to form a selective oxide film. At this time, the reaction material may be any one of O3, O2, H2O, H2O2, N2O, or NH3.

[0156]

[0157] Subsequently, a purge gas (e.g., an inert gas such as Ar) is supplied to the inside of the chamber to remove or purify residual reaction materials or byproducts.

[0158]

[0159] Subsequently, the substrate is exposed to an etching initiator supplied inside the chamber, and the etching initiator is adsorbed onto the substrate. Specifically, the etching initiator can be represented by the following <Chemical Formula 8>.

[0160] <Chemical Formula 8>

[0161]

[0162] In the above <Chemical Formula 8>, n is each independently selected from integers from 0 to 5, X1 to X3 are each independently selected from an alkoxy group having 1 to 5 carbon atoms and a dialkylamine group having 1 to 5 carbon atoms, and R is selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and a dialkylamine group having 1 to 5 carbon atoms.

[0163]

[0164] In addition, the etching initiator can be represented by the following <Chemical Formula 9>.

[0165] <Chemical Formula 9>

[0166]

[0167] In the above <Chemical Formula 8>,

[0168] X1 and X2 may each be the same or different from each other and are independently selected from hydrogen, a chlorine element, and a chloroalkyl group having 1 to 5 carbon atoms, and

[0169] R1 and R2 may each be the same or different from each other and are independently selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxyl group having 0 to 4 carbon atoms, and an alkoxy group having 0 to 4 carbon atoms.

[0170]

[0171] Subsequently, a purge gas (e.g., an inert gas such as Ar) is supplied to the inside of the chamber to remove or purify unadsorbed etching initiators or byproducts.

[0172]

[0173] Subsequently, the substrate is exposed to a reaction material supplied inside the chamber, and the reaction material reacts with an etching initiator to etch the inhibition film. At this time, the reaction material may be any one of O3, O2, H2O, H2O2, N2O, or NH3.

[0174]

[0175] Subsequently, a purge gas (e.g., an inert gas such as Ar) is supplied to the inside of the chamber to remove or purify residual reaction materials or byproducts. Etching is repeated until the inhibitor film is completely removed.

[0176]

[0177] Comparative Example - Formation of Inhibitory Film

[0178] EtMeCp-Nb=NtBu(Cl)2 was used as the first precursor to form the inhibition film. The inhibition film formation process is as follows, and the process was repeated 100 cycles at a process temperature of 300°C. The Nb content of each substrate with the inhibition film formed was analyzed by XPS.

[0179]

[0180] 1) Simultaneously loading a substrate with a silicon oxide film and a substrate with a silicon nitride film into the chamber

[0181] 2) Supply a first precursor into the reaction chamber using Ar as a carrier gas.

[0182] 3) Supply Ar gas into the reaction chamber to remove unadsorbed precursors or byproducts

[0183]

[0184] Example - Formation of inhibition film after surface treatment

[0185] Dichloromethyl methyl ether was used as a surface treatment agent, and the inhibition film formation process of Example 1 was carried out in the same manner as in Example 1, except that the following process was performed for one cycle at a process temperature of 300°C. The Nb content of each substrate with the inhibition film formed was analyzed by XPS.

[0186]

[0187] 1) Simultaneously loading a substrate with a silicon oxide film and a substrate with a silicon nitride film into the chamber

[0188] 2) Supply a surface treatment agent into the reaction chamber using Ar as a carrier gas.

[0189] 3) Supply Ar gas into the reaction chamber to remove unadsorbed surface treatment agents or byproducts

[0190]

[0191] Table 1 below shows the Nb content of each substrate in the comparative example / example, and Figure 4 is a graph showing the Nb content of the substrate according to the comparative example / example of the present invention.

[0192]

[0193] Surface treatment agent supply 1 precursor supply Nb% on SiNNb% on SiO2 Comparative Example X100 cycle 0.610.29 Example 1 cycle 100 cycle 0.250

[0194] In conclusion, it was confirmed that a niobium film was selectively formed on the nitride film, and that there was no niobium film on the oxide film using the method of the example.

[0195]

[0196] A surface treatment agent is supplied to increase the surface energy difference between the silicon oxide film and the silicon nitride (or silicon oxynitride) substrate; however, as the supply cycle of the surface treatment agent increases, the amount of agent adsorbed onto the substrate surface increases, causing a delay in the formation cycle of the inhibition film (incubation cycle delay).

[0197]

[0198] This weakens the surface reactivity of the oxide film relative to the nitride film due to the adsorption of the surface treatment agent, thereby reducing the adsorption amount of the subsequently supplied precursor, and consequently enables the selective formation of an inhibitory film on the surface of the nitride film.

[0199]

[0200] Furthermore, selective adsorption (Surface-dependent Adsorption) can be realized by utilizing the characteristic that the degree of precursor decomposition varies depending on the surface. On substrates with high surface energy, the precursor forms strong bonds through decomposition adsorption and is adsorbed in large quantities, whereas on substrates with low surface energy, the degree of ligand dissociation is low, forming weak bonds and adsorbing a relatively small amount.

[0201]

[0202] The surface treatment agent can be interpreted as supplying additional chlorine elements to the oxide film surface and forming strong bonds to further reduce the adsorption of the first precursor. This allows for the formation of an inhibitory film by minimizing the impact on the underlying oxide film, thereby replacing fluorine, which degrades device characteristics by damaging the thin film or causing impurity residue problems.

[0203]

[0204] Subsequent process - Formation of silicon oxide film after inhibition film formation

[0205] In the subsequent steps, the same process was applied to both the comparative example and the example.

[0206]

[0207] A substrate with a niobium oxide film and a substrate with a silicon oxide film were simultaneously loaded into a chamber to form a silicon oxide film. Diisopropylaminosilane (DIPAS) was used as the second precursor to form the silicon oxide film, and trimethyl orthoformate was used as a selectivity agent.

[0208]

[0209] The thin film formation process is as follows, and the process below was repeated for 200 cycles at a process temperature of 320°C. The thickness of the silicon oxide film formed on each substrate was analyzed.

[0210]

[0211] 1) Simultaneously loading a substrate with a niobium oxide film and a substrate with a silicon oxide film into the chamber

[0212] 2) Supply a selectivity agent into the reaction chamber and adsorb it onto the substrate.

[0213]

[0214] *3) Supply Ar gas into the reaction chamber to remove unadsorbed selectivity agents or byproducts

[0215] 4) Supply the second precursor into the reaction chamber using Ar as the carrier gas.

[0216] 5) Supply Ar gas into the reaction chamber to remove unreacted precursors or byproducts

[0217] 6) Supply O3 gas to the reaction chamber to form an oxide film.

[0218] 7) Supply Ar gas into the reaction chamber to remove unreacted materials or byproducts

[0219]

[0220] Figure 5 is a graph showing the result of selectively depositing a silicon precursor using a selectivity agent according to an embodiment of the present invention. It was confirmed that in a concurrent process, a silicon oxide film was selectively grown only on the oxide film, and that a silicon oxide film was not grown on the niobium oxide film for up to 100 cycles.

[0221]

[0222] Inhibitor film etching

[0223] A substrate with a niobium oxide film and a substrate with a silicon oxide film were simultaneously loaded into a chamber to perform an etching process. Dichloromethyl methyl ether was used as an etching initiator, and the following process was repeated 100 cycles at a process temperature of 340°C. The thickness of the oxide film on each substrate was analyzed.

[0224]

[0225] 1) Simultaneously loading a substrate with a niobium oxide film and a substrate with a silicon oxide film into the chamber

[0226] 2) Supply an etching initiator into the reaction chamber and adsorb it onto the substrate.

[0227] 3) Supply Ar gas into the reaction chamber to remove unadsorbed etching initiators or byproducts

[0228] 4) Supply O3 gas to the reaction chamber to etch the oxide film

[0229] 5) Supply Ar gas into the reaction chamber to remove unreacted materials or byproducts

[0230]

[0231] Figure 6 is a graph showing the result of selectively etching a metal oxide film using an etching initiator according to an embodiment of the present invention. It was confirmed that in a concurrently performed process, only the niobium oxide film was selectively etched and completely removed, and the thickness of the silicon oxide film was maintained at the same level as the initial state.

[0232]

[0233] FIG. 7 is a diagram schematically illustrating a thin film formation process according to another embodiment of the present invention, and FIG. 8 and FIG. 9 are graphs schematically illustrating a supply cycle according to another embodiment of the present invention.

[0234]

[0235] Unlike the embodiment described above, the inhibition film etching step may be further included after the inhibition film formation step and before the optional oxide film formation step, and the remaining process may be replaced by the description of the embodiment described above.

[0236]

[0237] Meanwhile, a surface treatment agent can be selectively supplied during the inhibition film formation stage.

[0238]

[0239] After the inhibition film formation step, a trace amount of inhibition film may be formed on the oxide films. The inhibition film etching step can remove the trace amount of inhibition film formed on the oxide films. The trace amount of inhibition film formed on the oxide films can be selectively removed using an etching initiator, and subsequently, a reaction material is supplied. Through the periodic repetition of supplying the etching initiator and the reaction material, a trap-cut structure in which the charge storage film is not connected can be formed by the selective formation of an oxide film. Therefore, the selectivity ratio can be increased by maximizing the surface difference due to the selective formation of an oxide film on the nitride film.

[0240]

[0241] Consequently, by implementing charge storage films separated between cells in a memory device, charge loss is reduced and the diffusion of charge in vertical and horizontal directions is suppressed, thereby enabling the realization of complete region-selective thin film formation (AS-ALD). In addition, charge retention characteristics in the memory device can be improved.

[0242]

[0243] Although the present invention has been described in detail through embodiments above, other forms of embodiments are also possible. Therefore, the technical concept and scope of the claims described below are not limited to the embodiments.

[0244] The present invention can be applied to various types of semiconductor manufacturing methods.

Claims

1. A step of providing a substrate having oxide films and nitride films alternately stacked on it; A step of forming an inhibitor film by selectively forming an inhibitor film on the nitride film; A selective oxide film formation step of selectively forming a selective oxide film on the oxide film; and A region-selective thin film formation method comprising a inhibition film etching step for removing the inhibition film.

2. In Paragraph 1, A method for forming a region-selective thin film, wherein the oxide film comprises silicon.

3. In Paragraph 1, A region-selective thin film formation method in which the above nitride film is a silicon nitride film or a silicon oxynitride film.

4. In Paragraph 1, The above inhibitory film formation step is, A surface treatment agent supply step of supplying a surface treatment agent into the interior of a chamber on which the above substrate is placed; A surface treatment agent purging step for purging the interior of the chamber; A step of supplying a first precursor into the interior of the chamber to selectively adsorb it onto the nitride film; and A region-selective thin film forming method comprising a first precursor purging step of purging the interior of the chamber.

5. In Paragraph 4, A region-selective thin film forming method, wherein the inhibition film forming step further comprises a reaction material supply step of supplying a reaction material to the interior of the chamber after the first precursor purging step.

6. In Paragraph 4, A region-selective thin film forming method in which the surface treatment agent supply step and the surface treatment agent purging step, the step of adsorbing the first precursor and the first precursor purging step are each repeated at least twice.

7. In Paragraph 4, The above surface treatment agent is a region-selective thin film forming method comprising a chlorine element.

8. In Paragraph 4, The above surface treatment agent is a region-selective thin film forming method represented by the following <Chemical Formula 1>. <Chemical Formula 1> In the above <Chemical Formula 1>, X1 and X2 may each be the same or different from each other and are independently selected from hydrogen, a chlorine element, and a chloroalkyl group having 1 to 5 carbon atoms, and R1 and R2 may each be the same or different from each other and are independently selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxyl group having 0 to 4 carbon atoms, and an alkoxy group having 0 to 4 carbon atoms.

9. In Paragraph 4, The above surface treatment agent is a region-selective thin film forming method represented by the following <Chemical Formula 2>. <Chemical Formula 2> In the above <Chemical Formula 2>, n is independently selected from integers 1 to 4, and R may be the same or different from each other and is selected from hydrogen atoms, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, and substituted alkyl cyclopentadienyl groups.

10. In Paragraph 1, A method for forming a region-selective thin film, wherein the above-mentioned inhibitory film is a metal-containing film having one of a trivalent metal, a tetravalent metal, or a pentavalent metal as a central element.

11. In Paragraph 4, A region-selective thin film forming method in which the first precursor is represented by the following <Chemical Formula 3>. <Chemical Formula 3> In the above <Chemical Formula 3>, n is selected from integers 1 to 3, M0 is selected from trivalent metal elements including Al, Ga, and In, and L0 and X0 may be the same or different from each other and are independently selected from hydrogen atoms, alkyl groups having 1 to 6 carbon atoms, dialkylamines, cycloamine groups, alkoxy groups, or halogen elements.

12. In Paragraph 4, A region-selective thin film forming method in which the first precursor is represented by the following <Chemical Formula 4>. <Chemical Formula 4> In the above <Chemical Formula 4>, n is selected from integers 1 to 4, and M1 is selected from tetravalent metal elements including Ti, Hf, and Zr, X1 is selected from halogen elements, and L1 may be the same or different from each other and is selected from hydrogen atoms, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, substituted alkyl cyclopentadienyl groups, alkoxy groups having 1 to 5 carbon atoms, alkylamino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, alkylimido groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, and aralkyl groups having 7 to 13 carbon atoms.

13. In Paragraph 4, A region-selective thin film forming method in which the first precursor is represented by the following <Chemical Formula 5>. <Chemical Formula 5> In the above <Chemical Formula 5>, n is selected from integers 1 to 5, and M2 is selected from pentavalent metal elements including V, Nb, and Ta, X2 is selected from halogen elements, and L2 may be the same or different from each other and is selected from hydrogen atoms, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, substituted alkyl cyclopentadienyl groups, alkoxy groups having 1 to 5 carbon atoms, alkylamino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, alkylimido groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, and aralkyl groups having 7 to 13 carbon atoms.

14. In Paragraph 1, The above selective oxide film formation step is, A step of supplying a selectivity agent to the interior of the chamber; A step of purging the interior of the above chamber; A step of supplying a second precursor to the interior of the chamber; A step of purging the interior of the above chamber; and A method for forming a region-selective thin film, comprising the step of supplying a reaction material into the interior of the chamber to react with the silicon precursor and form the selective oxide film.

15. In Paragraph 14, The above selectivity-imparting agent is a region-selective thin film forming method represented by the following <Chemical Formula 6>. <Chemical Formula 6> In the above <Chemical Formula 6>, n is each independently selected from integers from 0 to 5, X1 to X3 are each independently selected from an alkoxy group having 1 to 5 carbon atoms and a dialkylamine group having 1 to 5 carbon atoms, and R is selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and a dialkylamine group having 1 to 5 carbon atoms.

16. In Paragraph 14, The above second precursor is a region-selective thin film forming method represented by the following <Chemical Formula 7>. <Chemical Formula 7> In the above <Chemical Formula 7>, L may be the same or different from each other and is selected from hydrogen atoms, halogen elements, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, cyclopentadienyl groups, substituted alkyl cyclopentadienyl groups, alkoxy groups having 1 to 5 carbon atoms, alkylamino groups having 1 to 5 carbon atoms, dialkylamino groups having 1 to 5 carbon atoms, alkylimido groups having 1 to 5 carbon atoms, aryl groups having 6 to 12 carbon atoms, and aralkyl groups having 7 to 13 carbon atoms.

17. In Paragraph 14, The above inhibitor film etching step is, A step of supplying an etching initiator to the interior of the chamber; A step of purging the interior of the above chamber; A reaction material supply step for supplying a reaction material to the interior of the chamber; and A method for forming a region-selective thin film, comprising the step of purging the interior of the chamber.

18. In Paragraph 17, A region-selective thin film formation method in which the above etching initiator is represented by the following <Chemical Formula 8>. <Chemical Formula 8> In the above <Chemical Formula 8>, n is each independently selected from integers from 0 to 5, X1 to X3 are each independently selected from an alkoxy group having 1 to 5 carbon atoms and a dialkylamine group having 1 to 5 carbon atoms, and R is selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and a dialkylamine group having 1 to 5 carbon atoms.

19. In Paragraph 17, A region-selective thin film formation method in which the above etching initiator is represented by the following <Chemical Formula 9>. <Chemical Formula 9> In the above <Chemical Formula 9>, X1 and X2 may each be the same or different from each other and are independently selected from hydrogen, a chlorine element, and a chloroalkyl group having 1 to 5 carbon atoms, and R1 and R2 may each be the same or different from each other and are independently selected from hydrogen, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxyl group having 0 to 4 carbon atoms, and an alkoxy group having 0 to 4 carbon atoms.

20. In Paragraph 1, A method for forming a region-selective thin film, wherein the above inhibition film and the above selective oxide film are formed by atomic layer deposition (ALD).

21. In Paragraph 1, A region-selective thin film formation method in which the above-mentioned inhibitory film is removed by atomic layer etching (ALE).

22. In Paragraph 1, The above method, between the inhibition film formation step and the selective oxide film formation step, A region-selective thin film formation method further comprising a inhibition film etching step for removing an inhibition film formed on the oxide films.

23. In Paragraph 22, The above inhibitory film formation step is, A surface treatment agent supply step of supplying a surface treatment agent into the interior of a chamber on which the above substrate is placed; A surface treatment agent purging step for purging the interior of the chamber; A step of supplying a first precursor into the interior of the chamber to selectively adsorb it onto the nitride film; and It includes a first precursor purging step for purging the interior of the chamber, The above surface treatment agent is selectively supplied in a region-selective thin film formation method.

24. A method for manufacturing a memory device comprising a region-selective thin film forming method described in any one of claims 1 to 23.

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