Embedding method and substrate processing apparatus

Abstract

To improve the embeddability of a fluid film to be embedded in a recess.SOLUTION: A method for embedding a film in a recess of a substrate includes (a) preparing a substrate having a recess on a mounting table disposed in a chamber, (b) forming a fluid film inside the recess, and (c) supplying RF power to the mounting table and performing a first modification on the fluid film using the generated plasma.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an embedding method and a substrate processing apparatus.

Background Art

[0002] For example, Patent Document 1 proposes reacting an oxygen-containing silicon compound gas as a film-forming gas and a non-oxidizing hydrogen-containing gas with at least the non-oxidizing hydrogen-containing gas in a plasma state to form a fluid silanol compound on a substrate, and annealing the substrate to form an insulating film from the silanol compound.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technique capable of improving the embedding property of a fluid film embedded in a recess.

Means for Solving the Problems

[0005] According to one aspect of the present disclosure, a method for embedding a film in a recess of a substrate, comprising: (a) preparing a substrate having the recess on a stage disposed in a chamber; (b) forming a fluid film inside the recess; (c) supplying RF power to the stage to perform a first modification on the fluid film by the generated plasma. (c) above involves supplying a purge gas into the chamber after (b) above, and performing a first modification on the fluid film using the plasma of the purge gas. An embedding method is provided.

Effects of the Invention

[0006] According to one aspect, the embedding property of a fluid film embedded in a recess can be improved.

Brief Description of the Drawings

[0007] [Figure 1] A flowchart showing an example of an embedding method ST according to one embodiment. [Figure 2] A cross-sectional view of a membrane illustrating an embedding method ST according to one embodiment. [Figure 3] A diagram illustrating the failure of embedding the fluid film into the recess. [Figure 4] A diagram illustrating a reaction example when forming an SiO film by depositing and modifying a fluid film. [Figure 5] A diagram showing an example of the reaction when forming a SiN film by depositing and modifying a fluid film. [Figure 6] A diagram showing an example of the reaction when forming a BN film by depositing and modifying a fluid film. [Figure 7] A diagram showing an example of the reaction when forming a SiC film by depositing and modifying a fluid film. [Figure 8] A diagram showing an example configuration of a substrate processing apparatus according to one embodiment. [Modes for carrying out the invention]

[0008] The following describes embodiments for implementing this disclosure with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant explanations may be omitted.

[0009] In this specification, deviations in directions such as parallel, right angles, orthogonal, horizontal, vertical, up and down, and left and right are permitted to the extent that they do not impair the effects of the embodiment. The shape of the corners is not limited to right angles and may be rounded in an arc shape. Parallel, right angles, orthogonal, horizontal, vertical, circular, and coincidence may include approximately parallel, approximately right angles, approximately orthogonal, approximately horizontal, approximately vertical, approximately circular, and approximately coincidence.

[0010] [Embedding Method ST] First, an embedding method ST according to one embodiment will be described with reference to Figures 1 and 2. Figure 1 is a flowchart of an example of the embedding method ST according to one embodiment. Figure 2 is a cross-sectional view of a film for illustrating the embedding method ST according to one embodiment. In the embedding method ST of Figure 1, for example, a fluid film is embedded in a recess 101 of a substrate 100 using fluid CVD technology, as shown in Figure 2(a), and the fluid film is modified to form an insulating film or the like. This embedding process is performed, for example, by a substrate processing apparatus 1 (see Figure 8) described later. The substrate processing apparatus 1 includes a chamber 10, a mounting table 11 placed inside the chamber 10, an RF power supply 14 connected to the mounting table 11, a plasma source 2 and a control unit 130 located above the chamber 10 and supplying microwaves. The embedding method ST is controlled by the control unit 130.

[0011] (Step S1) First, in step S1 of Figure 1, the control unit 130 prepares a substrate 100 having recesses 101 on the mounting table 11. The substrate 100 to be prepared is not particularly limited, but a semiconductor substrate such as silicon is an example. The substrate 100 may have a fine three-dimensional structure on its surface. A fine three-dimensional structure is a structure on which a fine pattern is formed. The fine pattern has recesses 101, for example, as shown in Figure 2(a). The recesses 101 may be trenches or holes, for example. The substrate is not particularly limited.

[0012] The recess 101 is composed of an upper surface 101a, a bottom surface 101b, and a side surface 101c, and has an opening 101d that opens at the top of the recess 101. In step S1, the substrate 100 is loaded into the chamber 10 of the substrate processing apparatus 1.

[0013] (Step S2) Next, in step S2 of Figure 1, the control unit 130 forms a fluid film of a predetermined thickness within the recess 101. For example, as shown in Figure 2(b), a fluid film 200a of a predetermined thickness is formed within the recess 101.

[0014] As an example of the method for forming the fluid film 200a, a raw material gas, a hydrogen-containing gas, and a reaction accelerating gas are supplied into the chamber 10, microwave is supplied as an example of electromagnetic wave from the plasma source 2, plasma (also referred to as surface wave plasma) is generated above the chamber 10, and at least the reaction accelerating gas is reacted with the raw material gas and the hydrogen-containing gas in a plasma state. Thereby, the fluid film 200a is formed. In step S2, RF power is not supplied from the RF power supply 14 to the mounting table 11.

[0015] For example, a low-vapor-pressure oligomer shown in Fig. 3(a) is synthesized from tetraethoxysilane (TEOS; Si(OC2H5)4) gas, which is an example of Si raw material gas shown in Fig. 3, silane (SiH4) gas, which is an example of hydrogen-containing gas, and hydrogen gas, which is an example of reaction accelerating gas, and the fluid film 200a of the oligomer is generated. In this case, hydrogen gas is plasmaized using surface wave plasma, and the activated hydrogen radicals (H radicals: H * ) are reacted with TEOS gas, which is the raw material gas, and silane gas, which is the hydrogen-containing gas. The H radicals cut the bonds of TEOS gas and silane gas to synthesize a low-vapor-pressure oligomer as shown in Fig. 3(a).

[0016] During the film formation in step S2, the temperature inside the chamber is set to a low temperature (for example, less than 250°C) to make the fluid film 200a liquid. Utilizing the liquid property of this fluid film 200a, as shown by the arrow in Fig. 3(a), the fluid film 200a flows from the upper surface 101a of the recess 101 into the recess 101 and accumulates on the bottom surface 101b of the recess 101 as shown in Fig. 3(b).

[0017] However, when the opening 101d of the recess 101 becomes small, as shown in Fig. 3(c), the opening 101d is blocked by the fluid film 200a, void V is formed inside the recess 101, and embedding failure may occur. Also, when the viscosity of the fluid film 200a increases, this embedding failure is likely to occur. The increase in the viscosity of the fluid film 200a may be caused by cooling of the fluid film 200a on the substrate 100 controlled at a low temperature, increase in the molecular weight of the low-vapor-pressure oligomer, shortage of side-chain alkyl groups, etc.

[0018]

[0019] (Step S3) Next, in step S3 of FIG. 1, the control unit 130 supplies a purge gas into the chamber 10 to remove the raw material gas and the hydrogen-containing gas remaining in the chamber 10. As the purge gas, for example, an inert gas is used. As the inert gas, a noble gas such as Ar gas, or He gas or N2 gas is used. A gas that is likely to become plasma like Ar gas and a gas that is less likely to become plasma than Ar like N2 gas and has low reactivity and does not generate radicals may be mixed and used.

[0020] (Step S4) Next, in step S4 of FIG. 1, the control unit 130 performs a first modification on the fluid film.

[0021] In step S4, the control unit 130 supplies RF power (lower RF power) from the RF power supply 14 to the mounting table 11, and performs a first modification on the fluid film by the lower plasma of the generated purge gas. In step S4, no microwave is supplied from the plasma source 2. In step S4, in order to generate a weak plasma, low-power RF power (lower RF power) may be supplied from the RF power supply 14 to the mounting table 11.

[0022] Low-power RF power (lower RF power) refers to a power level (e.g., 500W or less) that does not decompose the molecules of the fluid film 200a. However, even if the RF power (lower RF power) is controlled to a low power level, if the raw material gas is present in the chamber 10, the RF power (lower RF power) supplied to the mounting stage 11 may decompose the raw material gas. Therefore, in step S3, the raw material gas is purged, and RF power (lower RF power) is supplied in an atmosphere such as Ar gas. This prevents the formation of a fluid film 200a with poor coverage due to the decomposition of the raw material gas in the first reforming step S4, while the fluid film 200a is pushed inward by collisions with Ar ions in the lower plasma. This improves the embedding of the fluid film 200a into the recess 101. In addition, the surface temperature of the fluid film 200a can be increased by the ionic energy of Ar ions in the lower plasma and the thermal energy from the plasma. As a result, by increasing the surface temperature of the fluid membrane 200a, the viscosity coefficient of the fluid membrane 200a can be lowered, thereby increasing the fluidity of the fluid membrane 200a. This makes it easier to push the fluid membrane 200a, which has decreased viscosity and increased fluidity, into the recess 101. In addition, the ions are attracted downward by the RF power (lower RF power). The fluid membrane 200a at the top of the recess 101 is subjected to a downward force due to the anisotropy of the kinetic energy of the ions caused by the physical collision of these ions. This allows the fluid membrane 200a, which is blocked at the opening 101d, to be pushed to the back of the recess 101 (towards the bottom surface 101b). As a result, the embedding ability of the fluid membrane 200a can be improved.

[0023] As a result, even if a highly viscous fluid film 200a is generated due to process conditions, for example, the generation of voids V can be avoided, and the embedding ability of the fluid film 200a into the recess 101 can be improved. As a result, the fluid film 200a at the opening 101d of the recess 101 shown in Figure 2(b) can be pushed into the back of the recess 101, and the upper part of the recess 101 can be opened, for example, in a V-shape, as shown in Figure 2(c).

[0024] In step S4, the RF power (lower RF power) may be a continuous wave or a pulsed wave. The microwave supplied from the plasma source 2 generates surface wave plasma at the top of the chamber 10. Therefore, it is difficult to promote the embedding of the fluid film 200a into the recess 101 of the substrate 100 located at the bottom of the chamber 10. For this reason, the supply of microwaves is stopped in step S4.

[0025] (Step S5) After step S4 in Figure 1, in step S5, the fluid film 200a is exposed to surface wave plasma to perform a second modification of the fluid film 200a.

[0026] For example, as shown in Figure 2(d), exposing the fluid film 200a to the generated surface wave plasma promotes chemical and physical reactions by radicals, electrons, and ions in the plasma, thereby modifying the fluid film 200a. As a result, the fluid film 200a changes from a liquid to a solid and is modified into a uniform film with good film properties. In the example of Figure 2(d), the substrate 100 is heated by a heating unit (heater, etc.) along with the modification by the surface wave plasma (radicals, electrons, ions). In this case, the fluid film 200a is modified by the energy of the surface wave plasma and the thermal energy from the heating unit. The formation of the fluid film 200a shown in Figure 2(b) and the first modification of the fluid film by low-power RF power (lower RF power) shown in Figure 2(c) can be performed in the same chamber 10. Furthermore, the second modification of the fluid film 200a by surface wave plasma shown in Figure 2(d) may be performed in the same chamber 10 or in a different chamber. The second modification in step S5 may be performed every time after the first modification in step S4, or at a predetermined frequency after the first modification in step S4, or it may not be performed at all.

[0027] (Step S6) Next, based on the determination made in step S6 of Figure 1, the control unit 130 repeats the processes in steps S2 to S5 a set number of times. As a result, the formation of the fluid film 200a, the first modification of the fluid film 200a, and the second modification of the fluid film 200a are repeated a set number of times, after which the process is terminated.

[0028] The method for embedding a film in the recess 101 described above includes (a) preparing a substrate having the recess 101 on the mounting table 11, (b) forming a fluid film 200a inside the recess 101, and (c) supplying RF power (lower RF power) from the RF power supply 14 to the mounting table 11 and performing a first modification of the fluid film 200a with the generated plasma.

[0029] In this embedding method, the formation of the fluid membrane 200a in (b) and the first modification of the fluid membrane 200a in (c) may be repeated to laminate multiple fluid membranes from the bottom surface 101b of the recess 101.

[0030] Furthermore, in this embedding method, after the first modification of the fluid membrane 200a in (c), a second modification may be performed on the fluid membrane 200a after the first modification by (d) electromagnetic wave energy and / or thermal energy due to heating.

[0031] Furthermore, in this embedding method, the formation of the fluid membrane 200a in (b), the first modification of the fluid membrane 200a in (c), and the second modification of the fluid membrane 200a in (d) may be repeated to laminate multiple fluid membranes from the bottom surface 101b of the recess 101. Multiple fluid membranes are collectively referred to as the fluid membrane 200a.

[0032] According to the above embedding method ST, as shown in Figure 2(e), the insulating film 300 formed by modifying each of the stacked fluid films 200a can be embedded in the recess 101 without voids. The modification of the fluid films 200a includes pressing the fluid films into the recess, solidification, and changes in film properties. After the deposition of the insulating film 300, a planarization (CMP) treatment may be performed.

[0033] Next, with reference to Figure 4, we will explain (1) the conditions for forming a fluid film, (2) the conditions for the first modification of the fluid film, and (3) the conditions for the second modification of the fluid film. Figure 4 is a diagram showing an example of the reaction when forming an SiO film by forming and modifying a fluid film. In Figure 4, we will explain using an example of forming an insulating film of SiO.

[0034] (1) Film formation conditions for fluid films (Figure 1, Step S2) (Gas type) To deposit the fluid film 200a, the chamber 10 is supplied with an oxygen-containing silicon compound gas and a non-oxidizing hydrogen-containing gas as film-depositing gases, as shown in Figure 4(a). In the example in Figure 4(a), the film-depositing gases are tetraethoxysilane (TEOS; Si(OC2H5)4) with an alkyl group (R) in a Si-O skeleton, and silane (SiH4) gas. Here, TEOS, silane (SiH4) gas, and H2 gas are supplied. TEOS is an example of an oxygen-containing silicon compound gas, and silane gas is an example of a hydrogen-containing gas.

[0035] Other examples of oxygen-containing silicon compound gases include tetramethoxysilane (TMOS; Si(OCH3)4), methyltrimethoxysilane (MTMOS; Si(OCH3)3CH3), dimethyldimethoxysilane (DMDMOS; Si(OCH3)2(CH3)2), triethoxysilane (SiH(OC2H5)3), and trimethoxysilane (SiH(O C Examples include H3)3) and trimethoxydisiloxane (Si(OCH3)3OSi(OCH3)3). These compounds may be used individually or in combination of two or more.

[0036] Other examples of hydrogen-containing gases include NH3 gas, which may be used alone or in combination of two or more. In addition to oxygen-containing silicon compounds and hydrogen-containing gases, inert gases such as He, Ne, Ar, Kr, and N2 may be supplied into the chamber. The hydrogen-containing gas may be at least one selected from H2 gas, NH3 gas, and SiH4 gas, or at least one of these may be further supplemented with at least one oxygen-containing gas such as O2 gas, NO, N2O, CO2, and H2O as an additive gas.

[0037] A plasma is generated, and the fluid film 200a is deposited by fluid CVD. The plasma generation method is not particularly limited, and various methods such as capacitively coupled plasma, inductively coupled plasma, and microwave plasma can be used. Furthermore, the plasma only needs to consist of a hydrogen-containing gas that has been plasma-generated. That is, both the film-depositing gas and the hydrogen-containing gas may be plasma-generated, or only the hydrogen-containing gas may be plasma-generated.

[0038] Here, H2 gas is converted into plasma. This plasma reaction deposits a fluid silanol compound onto the substrate as a fluid film 200a. Here, silanol compound refers to silicon-containing monomers and oligomers (multimers) having Si-OH groups.

[0039] Specifically, as shown in Figures 4(a) and (b), TEOS and silane gas generate H radicals (H) in the plasma from H2 gas. * It reacts with ), and alkyl groups and hydrogens are eliminated to form monomers of the silanol compound (e.g., orthosilicic acid or methyltriol). In addition, through reaction with plasma, a portion of the TEOS introduced as a film-forming gas polymerizes to form polysilanol oligomers, and similarly hydrocarbon groups are eliminated from the polysilanol oligomers to form oligomers of the silanol compound. The monomers and low vapor pressure oligomer silanol compounds thus generated on the substrate 100 are fluid and are embedded in the recesses 101 as a fluid film 200a.

[0040] (Temperature and pressure) From the viewpoint of ensuring the fluidity of the fluid film 200a, it is preferable to control the temperature of the substrate 100 (or the temperature of the mounting stage) to 250°C or less during the deposition of the fluid film 200a, more preferably -10°C to 100°C, and even more preferably -10°C to 50°C. Furthermore, during the deposition of the fluid film 200a, the pressure inside the chamber 10 is preferably 10 Pa to 2600 Pa.

[0041] (2) First modification conditions for the fluid membrane (Figure 1, Step S4) The RF frequency output from the RF power supply 14 is 100 Hz to 40 MHz. However, it is more preferable that the RF frequency output from the RF power supply 14 is 450 kHz to 13.56 MHz.

[0042] The RF power (lower RF power) is 10W to 500W. However, it is more preferable that the RF power (lower RF power) is 50 to 300W. Furthermore, the RF power (lower RF power) is dependent on the RF frequency, and it is preferable to lower the power as the RF frequency decreases. The pressure inside chamber 10 is 50Pa to 500Pa.

[0043] Low-power RF power (lower RF power) that satisfies the above conditions is supplied from the RF power supply 14 to the mounting stage 11. The purge gas, Ar gas, is plasma-generated by the low-power RF power (lower RF power), and the substrate 100 is exposed to the weak lower plasma formed near the mounting stage 11, thereby performing a first modification on the fluid film 200a.

[0044] Instead of supplying low-power RF power (lower RF power) to the mounting stage 11, it is conceivable to control the substrate temperature to improve the embedding ability of the fluid film 200a into the recesses 101. However, controlling the substrate temperature is time-consuming and reduces productivity. Furthermore, there may be constraints on temperature control as a process condition. This method makes it possible to improve the embedding ability of the fluid film without performing temperature control.

[0045] (3) Second modification conditions for the fluid membrane (Figure 1, Step S5) In the second modification of the fluidized film 200a, a surface wave plasma is generated to supply radicals, electrons, and ions to the fluidized film 200a. As a result, dehydration condensation and alkyl group R cleavage occur in the silanol compound, as shown in Figure 4(c). This causes excess substances such as H2O and RH to volatilize into the gas phase, forming Si-O-Si bonds and creating an SiO film with a Si-O network structure as an insulating film.

[0046] Furthermore, in the second modification, the substrate 100 is heated to modify the fluid film 200a by heat (annealing), changing the silanol compound embedded in the recesses 101 into a silicon-based insulating film. In the heat treatment, the molecules of the fluid film 200a are vibrated by thermal energy, and excess material is removed by the vibrational energy. Since heat does not involve impact by ions, etc., there is less physical damage to the structure having the recesses 101. Note that the second modification of the fluid film 200a may be performed using plasma alone or heat alone.

[0047] (Gas type) During the second reforming of the fluid film 200a, plasma may be generated using the gases used during the deposition of the fluid film 200a, excluding the source gas containing Si. For example, if a double source gas of TEOS gas and silane gas is used as the deposition gas, and hydrogen (H2) gas and argon (Ar) gas are also used during the deposition of the fluid film 200a, then during the second reforming of the fluid film 200a, H2 gas and Ar gas may be supplied to generate plasma.

[0048] (Temperature and pressure) The second modification of the fluid film 200a may be carried out in the same chamber 10 in which the fluid film 200a was deposited and the first modification was performed, or it may be carried out in a different chamber. When the second modification is carried out in a chamber different from the chamber 10 in which the first modification was performed, the temperature of the substrate in the chamber may be controlled to a temperature higher than the temperature of the substrate used when the fluid film 200a was deposited (250°C) from the viewpoint of promoting the modification.

[0049] (Types of insulating films) The insulating film 300 formed by depositing and modifying the fluid film 200a using the above embedding method ST can be an SiO film, a SiN film, a SiC film, a SiOCH film, a SiOC film, a BN film, a TiO film, or an AlO film. The raw material gas is one of a silicon-containing gas, a boron-containing gas, a titanium-containing gas, or an aluminum-containing gas.

[0050] Figure 5 shows an example of the reaction when forming a SiN film by depositing and modifying the fluid film 200a. Figure 6 shows an example of the reaction when forming a BN film by depositing and modifying the fluid film 200a. Figure 7 shows an example of the reaction when forming a SiC film by depositing and modifying the fluid film 200a.

[0051] When forming the SiN film shown in Figure 5, in order to deposit the fluid film 200a, the chamber 10 is supplied with a double-source gas as a film-forming gas, consisting of an organic aminosilane with an alkyl group (R) in a Si-N skeleton and silane (SiH4) gas, as shown in Figure 5(a). Furthermore, a hydrogen-containing gas and argon gas are supplied. Examples of organic aminosilanes include diethylaminotrimethylsilane, dimethylaminotrimethylsilane, ethylmethylaminotrimethylsilane, bis-butylaminosilane, trisdimethylaminosilane, 2,2,4,4,6,6-hexamethylcyclotrisilazane, and 1,3-diisopyramino-2,4-dimethylcyclosilazane.

[0052] As shown in Figures 5(a) and (b), the organic aminosilane reacts with a hydrogen-containing gas plasma (H and NH radicals) to form a fluidized film 200a of monomers and oligomers in which the Si-H and NR (and NC) bonds are broken and alkyl groups and hydrogen are removed.

[0053] Radicals, electrons, and ions are supplied to the chamber 10, and the fluid film 200a is exposed to the plasma for modification. The substrate 100 is also heated, and the fluid film 200a is heat-treated (annealed). As a result, as shown in Figure 5(c), cleavage of NH3 and alkyl group R occurs, and NH3 and RH volatilize into the gas phase, forming Si-N-Si bonds. Consequently, a SiN film having a Si and N network structure is formed as the insulating film 300.

[0054] When forming the BN film shown in Figure 6, in order to deposit the fluid film 200a, the chamber 10 is supplied with a double-source gas as a film-forming gas, consisting of an organic aminoborane gas with an alkyl group (R) in the BN skeleton and a diborane gas, as shown in Figure 6(a). Furthermore, a hydrogen-containing gas and an argon gas are supplied. Examples of organic aminoboranes include trisdimethylaminoborane, trisethylmethylaminoborane, and borazine.

[0055] As shown in Figures 6(a) and (b), the organic aminoborane reacts with a hydrogen-containing gas plasma (H and NH radicals), breaking the bond between BH and NR (and NC) and resulting in a fluidized film 200a of monomers and oligomers from which alkyl groups and hydrogen have been removed.

[0056] Radicals, electrons, and ions are supplied to the chamber 10, and the fluid film 200a is exposed to the plasma for modification. The substrate 100 is also heated to heat-treat (anneal) the fluid film. As a result, as shown in Figure 6(c), cleavage occurs of NH3 and alkyl groups R, causing NH3 and RH to volatilize into the gas phase, forming a BNB bond, and a BN film having a network structure of B and N is formed as the insulating film 300.

[0057] When forming the SiC film shown in Figure 7, in order to deposit the fluid film 200a, a double-source gas is supplied to the chamber 10 as the film-forming gas, as shown in Figure 7(a), and hydrogen-containing gas and argon gas are also supplied. In the example in Figure 7(a), the film-forming precursor is a double-source gas consisting of an organosilicon-containing gas with a Si-C framework and a silane gas. Examples of organosilicon-containing gases include bis-dichlorosilylmethylene and bis-trimethylsilylamine.

[0058] As shown in Figures 7(a) and (b), the organosilicon-containing gas reacts with the plasma (H radicals) of the hydrogen-containing gas, resulting in a fluidized film 200a of monomers and oligomers in which the Si-H and CH bonds are broken and hydrogen is removed.

[0059] Radicals, electrons, and ions are supplied to the fluid film 200a, and the fluid film 200a is modified by exposing it to plasma. In addition, the substrate 100 is heated to heat-treat (anneal) the fluid film. As a result, as shown in Figure 7(c), CH4 and H2 volatilize into the gas phase, C-Si-C bonds are formed, and a SiC film having a Si and C network structure is formed as the insulating film 300.

[0060] When forming a TiO film, a titanium-containing gas consisting of one of the following—a titanium compound, tetrakisdimethylaminotitanium, TiCp(NMe2)3, TiMe5Cp(NMe2)3, or titanium tetrachloride—is reacted with a hydrogen-containing gas, with at least the hydrogen-containing gas in a plasma state, to deposit a titanium compound containing fluid oxygen onto a substrate. Subsequently, the substrate is modified to use the oxygen-containing titanium compound as an insulating film.

[0061] In forming an AlO film, an aluminum-containing gas consisting of an aluminum compound, AICl3NH3, (NH4)3AIF6, or Al(i-Bu)3 is reacted with a hydrogen-containing gas, with at least the hydrogen-containing gas in a plasma state, to deposit a fluid, oxygen-containing aluminum compound onto a substrate. Subsequently, the substrate is modified to use the oxygen-containing aluminum compound as an insulating film.

[0062] [Substrate processing equipment] Next, an example of the configuration of the substrate processing apparatus 1 that performs the embedding method ST of this disclosure will be described with reference to Figure 8. Figure 8 is a diagram showing an example of the configuration of the substrate processing apparatus 1 according to one embodiment. The substrate processing apparatus 1 has a chamber 10.

[0063] The substrate processing apparatus 1 executes the embedding method ST under the control of the control unit 130, and embeds a fluid film in the recess 101 of the substrate 100 using fluid CVD technology within a chamber 10 under reduced pressure. The substrate processing apparatus 1 also performs at least a first modification on the fluid film to form an insulating film or the like. The substrate processing apparatus 1 may also perform a second modification on the fluid film after the first modification.

[0064] The configuration of the substrate processing apparatus 1 shown in Figure 8 is just one example, and the substrate processing apparatus 1 can be applied to any type of plasma processing apparatus, including Capacitively Coupled Plasma (CCP), Inductively Coupled Plasma (ICP), Micro Surface Wave Plasma, Electron Cyclotron Resonance Plasma (ECR), Helicon Wave Plasma (HWP), and Radial Line Slot Array Antenna (RLSA).

[0065] However, as shown in Figure 8, the substrate processing apparatus 1 can ensure plasma uniformity by arranging multiple independently controllable microwave plasma sources 2 in a plane. Furthermore, it can maintain the plasma over a wider pressure range compared to inductively coupled plasma (ICP). The substrate processing apparatus 1 also has a shower plate 20 structure that separates the substrate 100 from the plasma generation space, cuts out ionic components, and preferentially introduces radicals into the lower space, as well as a gas introduction structure that can supply multiple types of raw material precursors to the lower space where the substrate 100 is placed. In addition, the substrate processing apparatus 1 has a stage structure that controls the substrate to a temperature at which fluidity is exhibited. For these reasons, it is preferable to use the microwave plasma processing apparatus shown in Figure 8 as the substrate processing apparatus 1 for forming a fluid film 200a.

[0066] The substrate processing apparatus 1 comprises a substantially cylindrical, grounded chamber 10 made of a metal material such as aluminum or stainless steel, which is airtight, and a plasma source 2 for forming microwave plasma inside the chamber 10. An opening 1a is formed in the upper part of the chamber 10, and the plasma source 2 is positioned to face the inside of the chamber 10 through this opening 1a.

[0067] Inside the chamber 10, a mounting base 11 for horizontally supporting the substrate 100 is provided, supported by a cylindrical support member 12 erected in the center of the bottom surface of the chamber 10 via an insulating member 12a. Examples of materials constituting the mounting base 11 and the support member 12 include aluminum with anodized (anodic oxidation) surface treatment.

[0068] Although not shown in the diagram, the mounting table 11 is also provided with an electrostatic chuck for electrostatically adsorbing the substrate 100, a temperature control mechanism, a gas channel for supplying heat transfer gas to the back surface of the substrate 100, and lifting pins that move up and down to transport the substrate 100.

[0069] An exhaust pipe 15 is connected to the bottom of the chamber 10, and an exhaust device 16, including a vacuum pump, is connected to this exhaust pipe 15. By operating this exhaust device 16, the inside of the chamber 10 is evacuated, making it possible to rapidly reduce the pressure inside the chamber 10 to a predetermined vacuum level. In addition, an inlet / outlet 17 for loading and unloading substrates 100 and a gate valve 18 for opening and closing this inlet / outlet 17 are provided on the side wall of the chamber 10.

[0070] A shower plate 20 is horizontally positioned above the mounting base 11 inside the chamber 10. This shower plate 20 has a grid-like gas flow path 21 and numerous gas discharge holes 22 formed in this gas flow path 21, with spaces 23 between the grid-like gas flow path 21. A pipe 24 extending to the outside of the chamber 10 is connected to the gas flow path 21 of the shower plate 20, and a processing gas supply source 25 is connected to this pipe 24.

[0071] Meanwhile, a ring-shaped plasma generation gas introduction member 26 is provided along the chamber wall above the shower plate 20 of the chamber 10, and this plasma generation gas introduction member 26 has numerous gas discharge holes on its inner circumference. A plasma generation gas supply source 27, which supplies plasma generation gas (purge gas), is connected to this plasma generation gas introduction member 26 via piping 28.

[0072] Furthermore, an RF power supply 14 is electrically connected to the mounting base 11 via a matching unit 13. RF power (lower RF power) is supplied to the mounting base 11 from this RF power supply 14.

[0073] The plasma source 2 is positioned on a top plate 90 located at the top of the chamber 10. The plasma source 2 includes a microwave output unit 30 that distributes microwaves to multiple paths and outputs microwaves, and a microwave supply unit 40 that transmits the microwaves output from the microwave output unit 30 and radiates them into the chamber 10.

[0074] The microwave output unit 30 generates microwaves at a predetermined frequency (for example, 860 MHz) using, for example, a PLL oscillation. In addition to 860 MHz, the microwave frequency can be in the range of 700 MHz to 3 GHz.

[0075] The microwave supply unit 40 has multiple antenna modules 41 that guide the microwaves distributed by the distributor in the microwave output unit 30 into the chamber 10. Each antenna module 41 has an amplifier section 42 that mainly amplifies the distributed microwaves and a microwave radiating section 43. Microwaves are radiated into the chamber 10 from the antenna section of the microwave radiating section 43 in each antenna module 41. The microwave supply unit 40 has seven antenna modules 41, and the microwave radiating sections 43 of each antenna module are arranged in a circular pattern, with six in the circumference and one in the center, on a circular top plate 90.

[0076] The top plate 90 functions as a vacuum seal and microwave transmission plate and has a metal frame 90a and a dielectric member 90b made of a dielectric such as quartz, which is fitted into the frame 90a and provided to correspond to the portion where the microwave radiation section 43 is located. The top plate 90 closes the opening 1a of the chamber 10 via member 29.

[0077] The substrate processing apparatus 1 has a control unit 130. The control unit 130 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program that controls the processing of a substrate W, such as a semiconductor wafer, in the substrate processing apparatus 1. The program may be recorded on a computer-readable storage medium such as a computer-readable hard disk (HD), flexible disk (FD), compact disk (CD), magnetic optical disk (MO), or memory card, and installed from that storage medium to the control unit 130.

[0078] In the substrate processing apparatus 1 with the above configuration, when a fluid film 200a is formed, microwaves are output from the plasma source 2, and the supply of RF power (lower RF power) from the RF power supply 14 is stopped.

[0079] When forming the fluid film 200, the processing gas supplied by the processing gas supply source 25 can be the gas used to form the fluid film 200, for example, a double-source gas of TEOS gas and silane gas. Furthermore, H2 gas and Ar gas are preferably used as the plasma generation gas supplied by the plasma generation gas supply source 27. This allows the double-source gas to be kept from dissociating too much in the lower space, while the microwave surface wave plasma promotes the dissociation of H2 gas and Ar gas in the upper space.

[0080] During the first modification of the fluid film 200a, the microwave output from the plasma source 2 is stopped, and RF power (lower RF power) is supplied from the RF power supply 14. During the first modification of the fluid film 200, the supply of double source gas from the processing gas supply source 25 is stopped. Ar gas is preferably used as a purge gas from the plasma generation gas supply source 27. The supplied Ar gas is introduced into the lower space through the space 23 of the shower plate 20. The Ar gas is plasma-generated by the RF power (lower RF power) to generate the lower plasma. At this time, no surface wave plasma is generated by microwaves. Therefore, Ar ions in the lower plasma are drawn towards the substrate 100, and the first modification of the fluid film is performed.

[0081] As described above, according to the embedding method of this embodiment, the fluidity (viscosity) of the fluid membrane to be embedded in the recess 101 can be adjusted, thereby improving the embeddability of the fluid membrane.

[0082] The embedding method and substrate processing apparatus according to the embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The embodiments can be modified and improved in various ways without departing from the scope and spirit of the appended claims. The matters described in the above embodiments can be otherwise configured and combined in a non-consistent manner. [Explanation of Symbols]

[0083] 1. Substrate processing apparatus 2 Plasma source 10 Chambers 11. Mounting platform 14 RF power supply 100 circuit boards 101 Recess 101b Bottom 101d opening 200a fluid membrane 300 insulating film

Claims

1. A method for embedding a film in a recess of a substrate, (a) Prepare a substrate having the recess on a mounting platform placed inside the chamber, (b) Form a fluid film inside the recess, (c) RF power is supplied to the aforementioned stand, and the generated plasma is used to perform a first modification on the fluid film. Includes, (c) above involves supplying a purge gas into the chamber after (b) above, and performing a first modification on the fluid film using the plasma of the purge gas. Installation method.

2. (c) above performs a first modification on the fluid film using the ion energy of the plasma and the thermal energy of the plasma. The embedding method according to claim 1.

3. The process of forming the fluid film described in (b) and the first modification of the fluid film described in (c) is repeated. The embedding method according to claim 1 or 2.

4. The type of the fluid membrane is one of the following: SiO, SiN, SiC, SiOCH, SiOC, BN, TiO, or AlO membrane. The embedding method according to any one of claims 1 to 3.

5. A substrate processing apparatus having an RF power supply connected to the mounting stage and a plasma source positioned above the chamber and supplying electromagnetic waves, (b) above involves supplying a raw material gas, a hydrogen-containing gas, and a reaction-promoting gas into the chamber, and using electromagnetic waves supplied from the plasma source to react with the raw material gas and hydrogen-containing gas in a plasma state, thereby forming a fluid film, wherein the raw material gas is one of a silicon-containing gas, a boron-containing gas, an aluminum-containing gas, and a titanium-containing gas. (c) above supplies RF power from the RF power supply to the aforementioned mounting stand and performs the first modification on the fluid membrane. The embedding method according to any one of claims 1 to 4.

6. (d) The fluid film after the first modification is modified by the energy of electromagnetic waves supplied from the plasma source and / or the thermal energy from heating the stand described above. The embedding method according to claim 5.

7. A substrate processing apparatus having an RF power supply connected to the mounting stage, (b) above means stopping the supply of RF power from the RF power supply to the aforementioned mounting stand. The embedding method according to claim 4 or claim 5.

8. A substrate processing apparatus having a plasma source disposed above the chamber and supplying electromagnetic waves, (c) above is to stop the supply of electromagnetic waves from the plasma source. The embedding method according to any one of claims 4 to 6.

9. The frequency of the RF power is between 100 Hz and 40 MHz. The embedding method according to any one of claims 1 to 8.

10. The frequency of the RF power is 450 kHz to 13.56 MHz. The embedding method according to claim 9.

11. The aforementioned RF power is between 10W and 500W. The embedding method according to any one of claims 1 to 10.

12. The aforementioned RF power is between 50W and 300W. The embedding method according to claim 11.

13. The formation of the fluid film and the first modification of the fluid film are carried out in the same chamber. The embedding method according to any one of claims 1 to 12.

14. A substrate processing apparatus comprising a chamber, a mounting platform disposed within the chamber, an RF power supply and a control unit connected to the mounting platform, which performs a method of embedding a film in a recess of a substrate, The control unit controls the embedding method according to any one of claims 1 to 13. Circuit board processing equipment.

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