KR101732187B1 - METHOD OF FORMING CONFORMAL DIELECTRIC FILM HAVING Si-N BONDS BY PECVD - Google Patents

Abstract

A method for forming a conformal dielectric film having a Si-N bond on a semiconductor substrate by plasma enhanced chemical vapor deposition (PECVD) is a method for forming a conformal dielectric film having Si-N bonds on a semiconductor substrate by introducing a reactive gas containing nitrogen and hydrogen and a rare gas into a reaction space Applying RF power to the reaction space and introducing a silicon precursor pulse containing hydrogen upon plasma excitation into the reaction space to form a conformal dielectric film having Si-N bonds on the substrate.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a method of forming a conformal dielectric film having a silicon-nitrogen bond by plasma enhanced chemical vapor deposition (CVD)

The present invention relates to a method of fabricating a semiconductor integrated circuit, particularly a method of forming a conformal dielectric film such as a silicon nitride film, and a method of forming an etch of a dielectric film using an additive precursor by plasma enhanced chemical gas deposition (PECVD) Lt; / RTI >

Integrated circuits fabricated on a large scale integration semiconductor substrate require multiple levels of metal interconnections to electrically interconnect isolation layers of semiconductor devices formed on a semiconductor chip. The different levels of interconnects are separated by various insulating or dielectric layers, which are etched to form through the holes, allowing one level of metal to be connected to another metal.

Improvements in chip design continue to require faster circuitry and higher circuit densities than ever before. In fast circuits of high circuit density, certain properties require the materials used to fabricate the integrated circuit, particularly the size of the integrated circuit configuration to sub-micron dimensions. Further, in order to increase the density of the integrated circuit, a predetermined process sequence is required in the manufacture of the integrated circuit structure.

Recently, a silicon nitride layer deposited at low temperatures (less than 400 ° C) has been used in many important applications for memory devices such as, for example, passivation layers, surface protection layers and / or spacers for transistor gates. The silicon nitride film is formed by plasma enhanced chemical vapor deposition (PECVD). An important advantage of PECVD over other CVDs is its high deposition rate and ability to control a wide range of refractive indices. An additional advantage of the PECVD process is that the process is performed at a relatively low temperature, e.g., below 400 < 0 > C, while minimizing the total amount of heat treatment of the cell processing process.

However, the PECVD method of forming silicon nitride causes poor step coverage or poor conformality on low or high aspect ratio substrates. In small circuits and devices such as very large scale integration (ULSI) circuits, poor conformal coverage hinders the development of high density circuit devices and components.

Recently, atomic layer deposition (ALD) has been studied to improve the step coverage or conformality of a silicon nitride film on a substrate of small character. However, the ALD method of forming silicon nitride results in very poor deposition rates. The poor deposition rate does not reduce the manufacturing cost for developing high density circuit devices and components.

It is an object of at least one embodiment of the present invention to provide a method of forming a conformal layer having Si-N bonds and containing hydrogen, such as a silicon nitride layer, on a trench surface of an integrated circuit at low temperatures, .

It is an object of at least one embodiment of the present invention to provide a method of modifying the etch characteristics of a deposited layer, such as a wet etch rate, by adding a second precursor while maintaining a high deposition rate and high conformality.

According to an aspect of the present invention, there is provided a method of forming a conformal dielectric film having Si-N bonds on a semiconductor substrate by plasma enhanced chemical vapor deposition (PECVD) Introducing a reaction gas and a rare gas into a reaction space in which the semiconductor substrate is placed; Applying RF power to the reaction space; And introducing into the reaction space a precursor comprising silicon gas containing hydrogen at a pulse duration of less than 5 seconds during the introduction of the reactive gas and the rare gas without interference during plasma excitation, And forming a conformal dielectric film on the substrate.

Wherein the hydrogen containing silicon precursor is Si _? H _? X _{?, Where} ? And? Are integers and? Is an integer containing 0, and X is N, F and / or C _m H _n And m and n may be integers.

The hydrogen containing silicon precursor may be liquid at ambient temperature and be a vaporized upstream of the reaction space.

The hydrogen-containing silicon precursor may be introduced in a pulse during continuous inflow of the reaction gas and the additive gas and continuous application of the RF power.

The pulse duration may be equal to or less than the interval between pulses.

The hydrogen containing silicon precursor may be introduced at a pulse interval of approximately 0.1 to 3.0 seconds with a pulse duration of approximately 0.1-1.0 seconds.

The reaction gas may include at least one of a mixture of N ₂ and H ₂ , a mixture of NH ₃ and H ₂ , and a nitrogen-boron-hydrogen gas.

The rare gas may comprise a mixture of helium and argon or a mixture of helium and krypton.

The conformal dielectric film may be a silicon nitride film.

The silicon gas containing hydrogen may have no carbon atoms in its molecules and constitute a first precursor, and the precursor may further include a gas containing a hydrocarbon as a second precursor.

The first and second precursors may be introduced with pulses of the same timing.

The pulse duration of the second precursor may be different from that of the first precursor.

The conformal dielectric film may be a carbon doped silicon nitride film.

A method of forming a dielectric film having Si-N bonds on a semiconductor substrate by a plasma enhanced chemical vapor deposition method according to another embodiment of the present invention includes the steps of (i) supplying a reactive gas containing nitrogen and / Introducing the substrate into a reaction space in which the substrate is placed; (Ii) applying RF power to the reaction space; (Iii) introducing a hydrogen-containing silicon gas into the reaction space as a first precursor with a pulse of a duration of less than 5 seconds while introducing the reaction gas and the inert gas without interference during plasma excitation, Forming a first dielectric film having N bonds on the substrate; And (iv) repeating steps (i) to (iii) to form a second dielectric film having Si-N bonds on the substrate, wherein step (iii) comprises injecting the first precursor Further comprising the step of introducing a second precursor with a pulse to cause the wet etch resistance of the second dielectric film to increase relative to that of the first dielectric film, And more hydrocarbons.

The step (iv) may further comprise the step of extending the pulse duration of the second precursor relative to the pulse duration of the first precursor.

The step (iv) may further comprise reducing the nitrogen gas flow compared to the nitrogen gas flow for the first dielectric film.

A method of forming a dielectric film having Si-N bonds on a semiconductor substrate by plasma enhanced chemical vapor deposition according to another embodiment of the present invention includes the steps of (i) mixing a reactive gas containing nitrogen and / Into a reaction space in which a semiconductor substrate is located; (Ii) applying RF power to the reaction space; (Iii) introducing each of the first precursor and the second precursor into the reaction space with a pulse having a duration of less than 5 seconds at the same timing while introducing the reaction gas and the inert gas without interfering at the time of plasma excitation, Forming a first dielectric film on the substrate, wherein the first precursor is a silicon gas containing hydrogen and the second precursor has more hydrocarbons than the first precursor; And (iv) repeating steps (i) to (iii) to form a second dielectric film having Si-N bonds on the substrate, wherein step (iii) comprises forming the first and second precursors And introducing another second precursor with a pulse while introducing the second dielectric film into the second dielectric film to change the wet etch resistance of the second dielectric film relative to that of the first dielectric film.

The step (iv) may further comprise the step of varying it for the other second precursor for the pulse duration of the second precursor.

The step (iv) may further comprise the step of varying the nitrogen gas flow compared to the nitrogen gas flow for the second dielectric film.

According to the present invention, the etch characteristics of the dielectric layer formed on the semiconductor substrate can be altered or adjusted by using the additive precursor by using process control parameters in combination. And the dielectric layer can be formed at relatively low substrate temperatures and the film structure can be controlled to increase productivity and extend the applicable substrate form to the substrate without causing thermal damage. Also, the thickness can be controlled, a high deposition rate can be achieved, and a high conformal structure can be formed.

These and other features of the invention are set forth by way of example only and are not to be construed as limiting the present invention. The figures have been greatly simplified for illustrative purposes and do not necessarily represent a constant ratio.
1 is a schematic diagram of a PECVD apparatus for depositing a silicon nitride film in an embodiment of the present invention.
2A and 2B are process step diagrams of a comparative PECVD method and a PECVD method of an embodiment of the present invention for depositing a silicon nitride film.
3A and 3B are SEM (Scanning Electron Microscopy) photographs of a cross section of a conformal silicon nitride film formed in an embodiment of the present invention.
4 is an infrared spectroscopy (Fourier transform infrared (FT-IR)) spectrum of a conformal silicon nitride film formed in an embodiment of the present invention.
Figure 5 is a process step diagram of a PECVD process modified in an embodiment of the present invention.
6 is an FT-IR spectra diagram of a dielectric film in an embodiment of the present invention.
7 is a graph illustrating the wet etch rate of the dielectric layer in an embodiment of the present invention compared to that of a standard thermal oxide layer.
8 is a graph showing the relationship between the nitrogen flow rate, the wet etching rate and the carbon concentration in the film of an embodiment of the present invention.
9 is a graph showing the relationship between nitrogen flow and reflection index and Si / N ratio in an embodiment of the present invention.
10 is a graph showing the relationship between the hexane supply duration and the wet etch rate in an embodiment of the present invention.

In one embodiment of the present invention, a method is provided for forming a conformal dielectric film having Si-N bonds on a semiconductor substrate by plasma enhanced chemical vapor deposition (PECVD). The method includes introducing a reactive gas containing nitrogen and / or hydrogen and a rare gas into a reaction space in which a semiconductor substrate is placed, and RF power is applied to the reaction space. A precursor including a silicon-containing gas containing hydrogen is introduced into a pulse of a duration of less than 5 seconds while introducing the reaction gas and the rare gas without plasma excitation interference, thereby forming a conformal dielectric film having Si-N bonds on the substrate do. In the present disclosure, "gas" includes vaporized solids and / or liquids and may consist of a gas mixture.

In another embodiment, a method of forming a high conformal layer containing Si with N-Si bonds on a semiconductor substrate by plasma enhanced chemical vapor deposition (PECVD) CVD reaction chamber wherein the temperature of the semiconductor substrate is maintained in the range of approximately 0 to 400 占 폚. After the reaction gas and the additive gas are introduced into the reaction chamber, a plasma excited state is provided in the reaction chamber. The silicon precursor containing hydrogen is flowed into the reaction chamber in pulses using a pulse flow control valve, where the silicon precursor is introduced into the reaction chamber in which the plasma is excited and a Si-N bond is formed on the substrate by the plasma reaction of the gas And forms a conformal film containing hydrogen.

In an embodiment, the substrate is maintained at a temperature of about 0 to 400 캜. The hydrogen containing silicon precursor may be a compound of silicon and hydrogen; Compounds of silicon, hydrogen and nitrogen; Or a compound of silicon, hydrogen, carbon, and nitrogen. In an embodiment, the silicon precursor containing the vaporized hydrogen is introduced with a duration pulse of approximately 0.1 to 1.0 seconds at intervals between pulses of approximately 0.5 to 3 seconds while maintaining the plasma polymerization. In the embodiment, the reaction gas is a compound of a nitrogen gas and a hydrogen gas, or a compound of an ammonia gas and a hydrogen gas. In an embodiment, the additive gas is selected from the group consisting of He, Ar, Kr, Xe and the molar flow rate of the additive gas is greater than the molar flow rate of the silicon source containing hydrogen. In an embodiment, the reaction chamber is maintained at a pressure of about 0.1 to 10 Torr. In an embodiment, the RF power is between approximately 0.02 and 20 W / cm ² . After entering the chamber, the reaction gas reacts with a silicon precursor containing hydrogen supplied in a pulse by a plasma reaction to form a conformal film with Si-N bonds on the substrate surface.

In the embodiment, the silicon gas containing hydrogen further comprises, as a second precursor, a gas in which the molecule does not have carbon atoms and constitutes the first precursor, and the precursor thereof contains hydrocarbons. By adding the second precursor, for example, the wet etch rate of the final film can be significantly improved or adjusted.

In this context, the first and second precursors can be distinguished according to whether they contain carbon. The reaction gas is defined as a gas that does not have hydrocarbons and silicon. In the above description, there is no overlap between the first and second precursors and the reaction gas in gaseous form. In an embodiment, the first and second precursors are introduced with pulses of the same timing. In an embodiment, the pulse duration of the second precursor differs from that of the first precursor.

For the purpose of summarizing the advantages of the invention and the advantages achieved over the related art, certain objects and advantages of the invention are set forth in the present disclosure. Of course, all such objects and advantages are not necessarily achieved in accordance with a particular embodiment of the present invention. Thus, for example, one skilled in the art can embody the present invention in a manner that accomplishes or optimizes the advantages taught herein without necessarily achieving other objects or advantages as taught or illustrated herein.

Additional aspects, features and advantages of the present invention will become apparent from the following detailed description.

The present invention is illustrated by reference to embodiments which do not limit the invention. In addition, the components applied to the embodiments are freely applicable to other embodiments, and the components applied to the other embodiments can be replaced or exchanged with each other without specific conditions thereunder. Also, ranges indicated below include or exclude end points in the examples.

Embodiments provide a method of forming a conformal dielectric film having Si-N bonds on a semiconductor substrate by plasma enhanced chemical vapor deposition (PECVD), the method comprising: (a) performing a reaction comprising nitrogen and / Introducing the gas and the rare gas into the reaction space in which the semiconductor substrate is located; (b) applying RF power to the reaction space; And (c) introducing into the reaction space a precursor comprising a silicon gas containing hydrogen at a pulse duration of less than 5 seconds during the introduction of the reactive gas and the rare gas without plasma excitation interference, Forming a conformal dielectric film on the substrate.

In an embodiment, the hydrogen containing silicon precursor has the formula Si _? H _? X _?, Where?,? And? Are integers and? Comprises zero. X comprises N, F and / or C _m H _n , wherein m and n are integers. In an embodiment, a is 1 to 5, beta is 1 to 10, and y is 0 to 6. In an embodiment, m is 2 to 18 and n is 6 to 30.

In any of the preceding embodiments, the substrate is maintained at a temperature between 0 and 400 캜 while the film is deposited thereon. In some embodiments, the substrate temperature is between 250 and 350 < 0 > C during deposition.

In any of the preceding embodiments, the hydrogen containing precursor is upstream vaporized in the reaction space.

In any of the preceding embodiments, the hydrogen containing precursor is liquid at ambient temperature.

In any of the preceding embodiments, the hydrogen containing silicon precursor is pulsed during continuous injection of reactive gas and rare gas and continuous application of RF power.

In any of the preceding embodiments, the hydrogen containing silicon precursor is introduced with a pulse duration of approximately 0.1 to 1.0 second. In certain embodiments, the pulse of the silicon precursor containing hydrogen has a duration of from about 0.2 to about 0.3 seconds.

 In certain embodiments, the pulses of the silicon precursor containing hydrogen are separated at intervals of approximately 0.1 to 3.0 seconds. In some embodiments, the intervals are about 0.5 to 3.0 seconds or about 1.0 to 2.0 seconds. In an embodiment, the pulse duration is equal to or shorter than the interval.

In any of the preceding embodiments, the reaction gas comprises at least one of a mixture of N ₂ and H ₂ , a mixture of NH ₃ and H ₂ , and a nitrogen-boron-hydrogen gas. In an embodiment, the reaction gas comprises a mixture of N ₂ and H ₂ having a molar flow rate ratio of N ₂ / H ₂ of about 1/1 to 10/1. In some embodiments, N ₂ And the molar flow rate ratio of H ₂ is about 2/1 to 4/1. In an embodiment, the reaction gas comprises a mixture of NH ₃ and H ₂ having a molar flow rate ratio of NH ₃ / H ₂ of about 1/1 to 10/1. In some embodiments the molar flow rate ratio of NH ₃ / H ₂ is approximately 1: 3: 1 to 1.

In any one of the preceding embodiments, the additive gas is at least one gas selected from the group consisting of He, Ar, Kr, and Xe and the molar flow rate of the additive gas is greater than the molar flow rate of the silicon source containing hydrogen high. In an embodiment, the flow rate of the additive gas introduced into the reaction chamber is approximately 30 sccm to 3000 sccm. In some embodiments, the flow rate of the additive gas is between about 1500 sccm and 2500 sccm. In an embodiment, the additive gas comprises a mixture of helium and argon or a mixture of helium and krypton. In an embodiment, the additive gas comprises a mixture of helium and argon having a molar flow rate ratio of helium / argon of about 3/1 to 20/1. In some embodiments, the molar flow rate ratio of helium / argon is about 5/1 to 15/1. In an embodiment, the additive gas comprises a mixture of helium and krypton having a molar flow rate ratio of helium / krypton of about 3/1 to 20/1. In some embodiments, the molar flow rate ratio of helium / krypton is about 5/1 to 15/1.

In some embodiments, only three gas types (i. E., A silicon precursor containing hydrogen, a reactive gas, and an additive gas) are used, and no other gas, such as a carbon precursor, can be used.

In any of the preceding embodiments, the conformal dielectric film is a silicon nitride film.

In any of the preceding embodiments, the RF power is approximately 0.02 W / cm per area of the substrate² To 20 W / cm²(For example, 0.05-10 W / cm² , 1-5 W / cm² , And 0.5-3 W / cm²And the reaction space pressure is adjusted to a range of approximately 0.1 Torr to 10 Torr. In some embodiments, the pressure of the reaction space is approximately 2 Torr to 9 Torr.

In any of the preceding embodiments, the spacing and pulse duration of the pulses for introducing the hydrogen-containing silicon precursor is at least 80% (e. G., 80% to 95%) conformal or step coverage . In an embodiment, the spacing and pulse duration of the pulses for introducing the hydrogen-containing silicon precursor is such that the conformal dielectric film has a lower etch rate than the standard thermal oxide film when using buffered HF to perform a wet etch, for example. do. In an embodiment, the spacing and the pulse duration between pulses introducing a hydrogen-containing silicon precursor is greater than 1.0E-08 A / cm < ² > Of leakage current. In some embodiments, the leakage current is about 1.0E-08 A / cm < ² > at 1 MV And 1.0E-10 A / cm < ² > There is a liver.

In any of the preceding embodiments, the dielectric constant of the conformal dielectric film is in the range of 4.5 to 7.5. In some embodiments, the dielectric constant is about 6.5 to 7.2.

In any of the preceding embodiments, the hydrogen containing silicon precursor is vapor or liquid at ambient temperature. In some embodiments, the silicon precursor containing hydrogen is selected from the group consisting of silane, disilane, trisilylamine, bis (tert-butylamino) silane.

In some embodiments, the plasma reaction step may be performed using a frequency in excess of 5 MHz. For example, a high RF frequency power of 13.56 MHz, 27 MHz or 60 MHz is used. In some embodiments, high RF frequency power can be combined with low RF power of less than 5 MHz. In some embodiments, the ratio of low frequency power to high frequency power is 0 to 50% or less. In some embodiments, the ratio of low frequency power to high frequency power is 0-30% or less.

In any one of the preceding embodiments, the silicon gas containing hydrogen further comprises a gas having no carbon atoms in its molecule and a precursor containing a hydrocarbon as a second precursor. In an embodiment, the first and second precursors are introduced with pulses of the same timing. In an embodiment, the pulse duration of the second precursor differs from that of the first precursor.

In another aspect, an embodiment provides a method of forming a dielectric film having Si-N bonds on a semiconductor substrate by plasma enhanced chemical vapor deposition (PECVD), the method comprising: (i) depositing nitrogen and / And introducing the reactive gas and the rare gas into the reaction space in which the semiconductor substrate is placed; (Ii) applying RF power to the reaction space; (Iii) introducing a silicon gas containing hydrogen into a reaction space as a first precursor with a pulse of a duration of less than 5 seconds while introducing a reaction gas and an inert gas without interference during plasma excitation, thereby forming a Si- 1 dielectric film on the substrate; And (iv) repeating steps (i) to (iii) to form a second dielectric film having Si-N bonds on the substrate, wherein step (iii) is performed while introducing the first precursor with pulses of the same timing Further comprising introducing a second precursor with a pulse to increase the wet etch resistance of the second dielectric film relative to that of the first dielectric film, wherein the second precursor has more hydrocarbons in the molecule than the first precursor -.

In an embodiment, step (iv) further comprises extending the pulse duration of the second precursor relative to that of the first precursor. In an embodiment, step (iv) further comprises reducing the nitrogen gas flow compared to the nitrogen gas flow for the first dielectric film.

In another aspect, an embodiment provides a method of forming a dielectric film having Si-N bonds on a semiconductor substrate by plasma enhanced chemical vapor deposition (PECVD), the method comprising: (i) depositing nitrogen and / Introducing the reaction gas and the rare gas contained therein into the reaction space in which the semiconductor substrate is placed; (Ii) applying RF power to the reaction space; (Iii) introducing each of the first precursor and the second precursor into the reaction space with a pulse having a duration of less than 5 seconds at the same timing while introducing the reaction gas and the inert gas without plasma interference during the excitation, Forming a first dielectric film on the substrate, wherein the first precursor is a silicon gas containing hydrogen and the second precursor has more hydrocarbons than the first precursor; And (iv) repeating steps (i) to (iii) to form a second dielectric film having Si-N bonds on the substrate, wherein step (iii) comprises introducing the first and second precursors with pulses of the same timing And introducing another second precursor in a pulse during the second dielectric film to change the wet etch resistance of the second dielectric film relative to that of the first dielectric film.

In an embodiment, step (iv) further comprises changing it of a second precursor different than the pulse duration of the second precursor. In an embodiment, step (iv) further comprises varying the nitrogen gas flow relative to the nitrogen gas flow of the second dielectric film.

In any of the preceding embodiments, the substrate is maintained at a temperature of about 0 to 400 캜. The precursor containing Si (first precursor) is composed of a compound of silicon and hydrogen or a compound of silicon, hydrogen, nitrogen and carbon. The second precursor is composed of a compound of silicon, hydrogen and carbon or a compound of hydrogen and carbon. In an embodiment, the precursor containing the vaporized Si and the vaporized second precursor are introduced at a pulse duration of approximately 0.1 to 1.0 second at intervals of approximately 0.5 to 3 seconds while maintaining the plasma polymerization. In an embodiment, the reaction gas is a compound of nitrogen gas and hydrogen gas. In an embodiment, the addition precursor is NH ₃ or C _X H _Y Or a silicon precursor containing hydrocarbons, wherein x and y are integers. In an embodiment, x is from 1 to 8 and y is from 4 to 18. In an embodiment, the reaction chamber is maintained at a pressure of about 0.1 Torr to 10 Torr. In an embodiment, the RF power is approximately 0.01 W / cm < ² > And approximately 1.0 W / cm < ^{2 &} gt ;.

The following examples are set forth with reference to the drawings, which do not limit the invention. 1 is a schematic diagram of an apparatus incorporating a plasma CVD reactor and a flow control valve, which is preferably associated with a control program operating the sequence described below, which is used in the present invention.

In this example, pairs of electrically conductive flat plate electrodes 4,2 are provided in parallel and facing each other in the interior 11 of the reaction chamber 3, RF power 5 is applied to one electrode, 2 by electrically applying grounding 12 to excite the plasma between the electrodes. The temperature regulator is provided at the lower end (serving as the lower electrode 2), and the temperature of the substrate 1 thereon is constant at the set temperature. The upper electrode 4 also serves as a shower plate, and the reaction gas and the additive gas flow into the reaction chamber 3 through the gas flow controllers 21 and 22 and the shower plate. The silicon precursor containing hydrogen is introduced into the reaction chamber through the gas flow controller 23, the pulse flow control valve 31, and the shower plate 4. Further, in the reaction chamber 3, the exhaust pipe 6 discharges the gas in the interior 11 of the reaction chamber 3. The reaction chamber also includes a sealed gas flow controller 24 to introduce the sealed gas into the interior 11 of the reaction chamber 3. A separation plate for separating the reaction region and the transfer region inside the reaction chamber is omitted in this drawing. The sealing gas is not required but is used in some embodiments because it prevents the reaction gas from communicating underneath the chamber below the separator.

In the pulse flow control valve 31, a pulse supply valve used in ALD (atomic layer deposition) may be used in the embodiment.

Figure 2a shows the process steps of a comparative PECVD process and Figure 2b shows the process steps of an embodiment of the invention for depositing a silicon nitride film. The comparison method is carried out as shown in Fig. 2A, in which the main (silicon) precursor, the reaction gas and the additive gas are introduced into the reaction chamber in which the substrate is placed, and the plasma is excited while supplying all three gas forms. As a result, the silicon nitride film can be formed on the substrate by the plasma reaction. The silicon nitride film formed by the comparative PECVD method has a poor step coverage due to an excessive vapor phase reaction preventing the surface movement of the evaporation material.

In contrast, in an embodiment of the present invention, the silicon precursor is introduced into the reaction chamber with pulses of a duration of less than 5 seconds, preferably less than 2 seconds, effectively suppressing the excess gas phase reaction, resulting in step coverage or conformal Improve. For example, in the embodiment of the present invention shown in FIG. 2B, the silicon precursor is introduced into the reaction chamber through the pulse flow control valve for approximately 0.1 to 1 second, and then the pulse flow control valve is shut off for approximately 1 to 3 seconds . The introduction of the silicon precursor into the pulse is repeated. By doing so, large amounts of hydrogen and nitrogen are controlled to significantly enhance the stress of the hydrogen-nitrogen compound deposited film, and large amounts of hydrogen and nitrogen significantly increase H ^* , N ^* radicals during film growth Process to improve the surface movement of the deposition material to form a highly conformal silicon nitride film on the substrate.

In an embodiment, the average thickness deposited per cycle is 0.6-1.0 nm / cycle. The pulse supply of the silicon precursor continues until a desired film thickness is obtained. In the case of a preferable film thickness of 20 to 100 nm, about 20 to 150 cycles (for example, 40 to 100 cycles) are operated.

In embodiments using a particular single wafer PECVD reactor, when the supply pulse is less than 0.1 second, the deposition rate is slow and the uniformity of the deposition film is poor because the amount of precursor supplied is not sufficient to deposit and grow a uniform film to be. On the other hand, if the feed pulse exceeds 1.0 second, step coverage is poor (less than 80%) due to excess gas phase reaction. In an embodiment, in a high step coverage structure, excess gas phase reaction must be avoided and surface movement must occur during deposition. The pulse supply sequence of Figure 2B provides a variable that can be adjusted to realize the content. In an embodiment, when the interval between pulses is less than 0.1 seconds and the supply duration is 0.1 to 1.0 seconds, step coverage is poor. On the other hand, when the interval between pulses exceeds 3.0 seconds and the supply duration is 0.1 to 1.0 second, the film profile and step coverage do not actually affect, but the entire process becomes too long.

In embodiments of the present invention, the conformality of the film can be significantly improved compared to other silicon nitride deposition processes.

When the conformal silicon nitride layer is formed on a semiconductor substrate, the deposition conditions of the embodiment are as follows:

Silane: 10-200 sccm

Hydrogen: 500 to 2000 sccm

Nitrogen: 1000 to 2000 sccm

Helium process: 500-3000 sccm

Sealed helium: 500 sccm

Argon: 50-500 sccm

Substrate temperature: 0 to 400 ° C

RF power: 0.02 to 20 W / cm ²

Pressure: 0.1 to 10 Torr

Silane supply time: 0.5 to 1 second supply, 1 to 3 second supply stop

In an embodiment, the step coverage (conformal) of the resulting silicon nitride film is greater than 80% and the step coverage is greater than the average of the silicon nitride layer deposited on the sidewall of the trench relative to the average thickness of the silicon nitride film on the upper surface of the substrate It is defined as a percentage of the thickness. The leakage current is approximately 1.0E-08 A / cm ² at 1 MV charge . Also, in another embodiment, the reflection index (n) at 633 nm is in the range of approximately 1.80 to 2.60.

Another advantage of the conformal silicon nitride deposition process is its compatibility with silicon precursors containing liquid hydrogen. The deposition conditions in the examples are as follows:

Trisilylamine: 10 to 2000 sccm

Hydrogen: 500 to 2000 sccm

Nitrogen: 500 to 2000 sccm

Helium process: 0-5000 sccm

Sealed helium: 500 sccm

Argon: 50-500 sccm

Substrate temperature: 0 to 400 ° C

RF power: 0.02 to 20 W / cm ²

Pressure: 0.1 to 10 Torr

Trisilylamine supply time: 0.1 to 0.5 sec supply, 0.1 to 2 sec supply stop

In an embodiment of the present invention, the silicon nitride layer may have a conformality exceeding about 80% or 90%. The leakage current is approximately 1.0E-08 A / cm ² at 1 MV charge . Further, in another embodiment, the dielectric constant is about 6.7 to 7.3. In an embodiment, the reflection index (n) at 633 nm is in the range of about 1.80 to 2.60. The etch rate of the deposited silicon nitride film in the embodiment of the present invention is 2 to 10 times lower than that of the conventional thermal silicon oxide film when measured using buffered hydrogen fluoride.

In an embodiment, the first precursor is of the formula Si _? H _? X _?, Where?,? And? Are integers and? Comprises zero. X may include N or C _m H _n . In an embodiment, a is 1 to 5, beta is 1 to 10, and y is 0 to 6. In the examples, m is 2 to 18 and n is 6 to 30.

In an embodiment, the second precursor is ammonia or C _x H _y Or a silicon precursor containing hydrocarbons, wherein x and y are integers. In the examples, x is from 1 to 8 and y is from 4 to 18. In an embodiment, the silicon precursor containing hydrocarbons has the formula Si _? H _? X _?, Where?,? And? Are integers. X may include N or C _m H _n . In an embodiment, a is 1 to 5, beta is 1 to 10, and y is 1 to 6. In the examples, m is 2 to 18 and n is 6 to 30.

In some embodiments, the first precursor does not contain carbon while the second precursor contains hydrocarbons. In some embodiments, the first and second precursors contain hydrocarbons while the second precursor has more hydrocarbons in the molecule than the first precursor. In some embodiments, the first precursor contains silicon, while the second precursor does not contain silicon. In some embodiments, the first precursor contains nitrogen while the second precursor does not contain nitrogen. The first and second precursors may be defined by the definition of the preceding compounds. In some embodiments, more than two types of precursors can be used.

In any of the preceding embodiments, the substrate is maintained at a temperature of 0 to 400 캜 while depositing a film thereon. In some embodiments, the substrate temperature is about 300-400 占 폚 during the deposition.

In any of the preceding embodiments, the first and second precursors are introduced into the pulse while the reactive gas and the rare gas are continuously introduced and RF power is continuously applied. In any of the preceding embodiments, the first and second precursors are maintained for a time period of about 0.1 to 1.0 seconds (e.g., 0.2 to 0.3 seconds) at intervals of about 0.1 to 3.0 seconds (e.g., 1.0 to 2.0 seconds) Period. ≪ / RTI > In an embodiment, the pulse duration of the first and second precursors is equal to or less than the interval.

In any of the preceding embodiments, the reaction gas comprises a mixture of nitrogen and hydrogen, or a mixture of nitrogen-boron-hydrogen gas. In an embodiment, the reaction gas comprises a mixture of nitrogen and hydrogen having a molar flow rate ratio of N ₂ / H ₂ of about 1/10 to 10/1. In some embodiments, N ₂ And the molar flow rate ratio of H ₂ is about 1/4 to 4/1.

In any one of the preceding embodiments, the rare gas is at least one gas selected from the group consisting of He, Ar, Kr, and Xe and the molar flow rate of the rare gas is selected from the group consisting of a silicon source containing hydrogen (the sum of the first and second precursors ) ≪ / RTI > In an embodiment, the flow rate of the rare gas introduced into the reaction chamber is about 40 to 4000 sccm. In some embodiments, the flow rate of the rare gas is from about 1500 to 3000 sccm. In an embodiment, the rare gas comprises a mixture of helium and argon or a mixture of helium and krypton. In an embodiment, the rare gas comprises a mixture of helium and argon having a molar flow rate ratio of helium / argon of about 1/1 to 20/1. In some embodiments, the molar flow rate ratio of helium and argon is about 2/1 to 10/1. In an embodiment, the rare gas comprises a mixture of helium and krypton with a molar flow rate ratio of helium / krypton of about 2/1 to 10/1.

In any of the preceding embodiments, the RF power is in the range of about 0.01 to 1.0 W / cm ² per area of the substrate (e.g., 0.02-0.1 W / cm ² , 0.1-0.5 W / cm ² , 1 W / cm < ² >) and the reaction space pressure is adjusted to a range of approximately 0.1 to 10 Torr (e.g., 2 to 9 Torr).

In any of the preceding embodiments, the dielectric film formed has at least 80% (e. G., 80% to 95%) conformal or step coverage. In an embodiment, the formed dielectric film has a dielectric constant of 1.0E-08 A / cm < ² > (For example, 1.0E-08 to 1.0E-10 A / cm ² ) Leakage current.

In any of the preceding embodiments, the dielectric film formed has several etch resistances in accordance with the second precursor pattern. In an embodiment, a dielectric film formed using a silicon precursor containing hydrocarbons or hydrocarbons as a second precursor has a lower etch rate than a standard thermal oxide film. The etch resistance is increased by increasing the amount of carbon in some embodiments.

Also, the plasma emission step is performed using any of the high RF frequency powers of frequencies above 5 MHz in embodiments, e.g., 13.56 MHz, 27 MHz or 60 MHz; Furthermore, either the higher RF frequency power and the lower RF power below 5 MHz can be combined, wherein the ratio of the lower frequency power to the higher frequency power is less than 50% (e.g., less than 30%).

Figure 5 shows the process steps of an embodiment of the present invention for depositing a dielectric film with adjusted etch characteristics. 5, the main precursor (the first precursor) and the addition precursor (the second precursor) are maintained at about 0.1 < RTI ID = 0.0 > To 1.0 second. As a result, a large amount of hydrogen, nitrogen, and carbon are added to the process that significantly increases Hx, Nx, and Cx radicals during film growth, thereby improving the surface absorption of the deposition material so that a carbon- And is formed at a high deposition rate. Further, the constitution of the deposited film can be changed by adding an addition precursor. The addition of the additive precursor causes a change in performance characteristics such as wet etch rate in etchant.

When forming a dielectric layer having a good etching property on a semiconductor substrate, the deposition conditions are as follows in the embodiment:

Trisilylamine (first precursor): 10 to 2000 sccm (preferably 100 to 500 sccm)

Hydrogen: 20-2000 sccm (preferably 500-1000 sccm)

Nitrogen: 0-5000 sccm (preferably 20-2000 sccm)

Hexane (second precursor): 0-2000 sccm (preferably 100-1500 sccm)

Flow ratio of the second precursor to the first precursor: 0 to 5 (preferably 1 to 3)

Diethylsilane: 0-2000 sccm (preferably 100-500 sccm)

Bis (ethylmethylamino) silane: 0-2000 sccm (preferably 100-500 sccm)

Helium process: 0-5000 sccm (preferably 500-1500 sccm)

Sealed helium: 200-500 sccm (preferably 300-500 sccm)

Argon: 50-2000 sccm (preferably 500-1500 sccm)

Substrate temperature: 0-400 占 폚 (preferably 300-400 占 폚)

High frequency RF power: 0.01 W / cm ² To about 0.3 W / cm < ² > (preferably 0.02-0.08 W / cm < ² &

Low frequency RF power: 0-100% (preferably 0-50%) of high frequency RF power

Trisilylamine supply time: 0.1-1.0 sec supply (preferably 0.2-0.5 sec), 0.1-2.0 sec supply interruption (preferably 1.0-2.0 sec)

Addition precursor (hexane) Feed time: 0.1-1.0 sec Feed (equal to or longer than the first precursor feed time, preferably 0.2-0.5 sec, at the same pulse timing as the first precursor feed)

In this context, other gas forms described in this disclosure may be used alternatively or additionally in other embodiments. For example, instead of hexane, bis (ethylmethylamino) silane or diethylsilane can be used as the second precursor. Preferably, the second precursor has more hydrocarbons in its molecule than the first precursor, thereby binding more carbon to the SiN structure (carbon-doped silicon nitride). In an embodiment, the carbon content of the SiN dielectric layer (where the Si-N bond is the main or dominant bond) is in the range of 4 atom% to 20 atom%, preferably more than 5 atom% Atomic%). The second precursor need not contain silicon in the examples.

In an embodiment of the present invention, the dielectric layer has a conformality exceeding about 90%. The reflection index (n) measured at 633 nm is in the range of about 1.80 to 2.80. The etch rate of the dielectric film deposited in an embodiment of the present invention, as measured using an acid solution containing hydrofluoric acid, can be changed by adding an additive precursor. The wet etch rate of the dielectric layer obtained using the first and second precursors may range from 1/20 to 1/400 (e.g., less than 1/100) of the wet etch rate of the standard thermal oxide layer, depending on the type of the second precursor, Can be surprising and unpredictable. The wet etch rate of the dielectric layer obtained without the use of the second precursor is from 1/3 to 1/5 of the wet etch rate of the standard thermal oxide layer in some embodiments.

The embodiments are described with reference to specific examples that do not limit the invention. The value applied to the specific example may be varied in the range of at least +/- 50% under different conditions, wherein the end point of the range is included or excluded. In this disclosure, which does not specify conditions and / or structures, one skilled in the art can readily provide the conditions and / or structures when reviewing the present disclosure in routine experimentation.

Example 1

An insulating silicon nitride layer is formed on the substrate with the trenches under the conditions shown below using the sequence illustrated in Figure 2B and the PECVD apparatus illustrated in Figure 1. The trenches include relatively wide trenches (width 500 nm and depth 350 nm) and relatively narrow trenches (width 50 nm and depth 350 nm). Therefore, trenches of different aspect ratios are coated.

Silane: 50 sccm

Hydrogen: 1000 sccm

Nitrogen: 2000 sccm

Helium process: 2000 sccm

Sealed helium: 500 sccm

Argon: 100 sccm

Substrate temperature: 300 DEG C

RF power (at a frequency of 13.56 MHz): 0.12 W / cm ²

Pressure: 6 Torr

Silane supply time: 1 second supply, 3 second supply stop

After deposition is complete, the trenches are observed with a scanning electron microscope.

The step coverage defined by the ratio of the sidewall thickness to the thickness of the upper coverage is greater than 80% (80-87%). In contrast, the film obtained by the process after the sequence illustrated in FIG. 2A has a step coverage of less than 70%.

Example 2

An insulating silicon nitride layer is formed on the substrate with the trenches under the conditions shown below using the sequence illustrated in Figure 2B and the PECVD apparatus illustrated in Figure 1. The trenches include relatively wide trenches (width 500 nm and depth 350 nm) and relatively narrow trenches (width 50 nm and depth 350 nm).

Trisilylamine: 300 sccm

Hydrogen: 500 sccm

Nitrogen: 1000 sccm

Helium process: 1400 sccm

Sealed helium: 500 sccm

Argon: 500 sccm

Substrate temperature: 300 DEG C

RF power (at a frequency of 13.56 MHz): 0.12 W / cm ²

Pressure: 6 Torr

Trisilylamine supply time: 0.2 sec supply, 2 sec supply stop

After deposition is complete, the trenches are observed with a scanning electron microscope (SEM).

Figures 3a and 3b show a cross-section of a substrate with a conformal silicon nitride layer formed thereon by scanning electron microscopy. Qualitatively, the silicon nitride layer is highly conformal and completely covers the trench sidewalls. The silicon nitride layer has a conformality of 88% (43.7 / 49.6) shown in FIG. 3A (a = 43.7 nm, b = 49.6 nm, c = 41.7 nm) (49.6 / 51.6) shown in Fig. The measured leakage current is lower than 1.0E-08 A / cm ² at 1 MV charge. Its dielectric constant is 6.8 at 1 MHz. At 633 nm the reflection index (n) is 1.99. Figure 4 shows the IR absorption spectra of a deposited silicon nitride film. As shown in Fig. 4, main Si-N bonds are observed and weak bonds of Si-H and NH are also observed. As measured using buffered hydrogen fluoride, the etch rate of the silicon nitride film deposited in this example is four times lower than that of the conventional thermal oxide silicon film. The etching test is carried out using a BHF 130 etchant. The deposited film (SiN) on the Si substrate is placed in the BHF 130 in the atmosphere for 5 minutes and then washed with deionized water. The film thickness is measured by an ellipsometer.

An important advantage of at least one of the disclosed embodiments of the present invention is that a high conformal silicon nitride layer or other Si-N dielectric layer can be formed on various types of substrates. Silicon nitride coatings or other Si-N dielectric films are also formed at relatively low substrate temperatures to increase productivity for the substrate and extend the applicable substrate form without thermal damage or wear of the excess thermal throughput. In addition, the method of embodiments of the present invention can achieve high deposition rates and can be easily measured, such as three-dimensional integration of die-to-wafer or wafer-to-wafer Enabling three-dimensional production and / or large scale applications.

Example 3

The dielectric layer is formed on the substrate without the addition precursor under the conditions shown below based on the sequence illustrated in Fig.

Trisilylamine: 100 sccm

Hydrogen: 500 sccm

Nitrogen: 1000 sccm

Helium process: 1400 sccm

Sealed helium: 500 sccm

Argon: 1000 sccm

Substrate temperature: 400 DEG C

High frequency RF power (frequency 13.56 MHz): 0.07 W / cm ²

Low frequency RF power (frequency 430 kHz): 0.0 W / cm ²

Trisilylamine supply time: 0.3 sec supply, 2.0 sec supply stop

In this case, the film thickness per cycle is approximately 0.20 nm / cycle. 6 (TSA: line (a)) shows the IR absorption spectrum of the deposited SiN film obtained in Example 3. Fig. The dielectric film deposited without the addition precursor has a wet etch rate of 4.1 nm / min as shown in Figure 7 (TSA). The etching test is carried out using a BHF 130 etchant. The deposited film on the Si substrate is immersed in the etch for 5 minutes and then washed with deionized water. The film thickness is measured by an ellipsometer.

Example 4

The dielectric layer is formed as bis (ethylmethylamino) silane, which is an addition precursor on the substrate under the conditions shown below, using the sequence illustrated in FIG.

Trisilylamine: 100 sccm

Hydrogen: 500 sccm

Nitrogen: 0 sccm

Bis (ethylmethylamino) silane: 300 sccm

Helium process: 1400 sccm

Sealed helium: 500 sccm

Argon: 1000 sccm

Substrate temperature: 400 DEG C

High frequency RF power (frequency 13.56 MHz): 0.07 W / cm ²

Low frequency RF power (frequency 430 kHz): 0.0 W / cm ²

Trisilylamine supply time: 0.3 sec supply, 2.0 sec supply stop

Bis (ethylmethylamino) silane: 0.3 sec supply, 2.0 sec supply cut

In this case, the film thickness per cycle is approximately 0.25 nm / cycle. Figure 6 (TSA + BEMAS: line (b)) shows the IR absorption spectrum of the deposited C-doped SiN film obtained in Example 4, where the Si-CH peak (1130-1090 cm ^-1 ) and the -CH x peak . The deposited dielectric film with the addition of bis (ethylmethylamino) silane has a wet etch rate of 0.9 nm / min in the BHF 130 etchant as shown in FIG. 7 (BEMAS).

Example 5

The dielectric layer is formed with diethylsilane as an addition precursor on the substrate under the conditions shown below using the sequence illustrated in Fig.

Trisilylamine: 100 sccm

Hydrogen: 500 sccm

Nitrogen: 0 sccm

Diethylsilane: 300 sccm

Helium process: 1400 sccm

Sealed helium: 500 sccm

Argon: 1000 sccm

Substrate temperature: 400 DEG C

High frequency RF power (frequency 13.56 MHz): 0.07 W / cm ²

Low frequency RF power (frequency 430 kHz): 0.0 W / cm ²

Trisilylamine supply time: 0.3 sec supply, 2.0 sec supply stop

Diethylsilane: 0.3 sec supply, 2.0 sec supply stop

In this case, the film thickness per cycle is approximately 0.11 nm / cycle. Figure 6 (DES TSA +: line (c)) shows a C- doped SiN film as-deposited IR absorption spectrum obtained in the Example 5, wherein the main peak is 800 cm from 835 cm ^{-1 - 1} is moved. The SiN absorption peak usually appears in the range of 812 cm ^-1 to 892 cm ^-1 (for example, Si ₃ N ₄ appears at around 830 cm ^-1 ), while the SiC absorption peak is in the range of 900 to 700 cm ^-1 , Lt; ^-1 > cm < ^-1 > The shift of the absorption peak indicates that carbon is present in the deposited film. The deposited dielectric film to which diethylsilane is added has a wet etch rate of 0.05 nm / min in a BHF 130 etchant.

Example 6

The dielectric layer is formed with an additive precursor, e. G., Hexane, on the substrate under the conditions shown below using the sequence illustrated in Fig.

Trisilylamine: 100 sccm

Hydrogen: 500 sccm

Nitrogen: 0 sccm

Hexane: 300 sccm

Helium process: 1400 sccm

Sealed helium: 500 sccm

Argon: 1000 sccm

Substrate temperature: 400 DEG C

High frequency RF power (frequency 13.56 MHz): 0.07 W / cm ²

Low frequency RF power (frequency 430 kHz): 0.0 W / cm ²

Trisilylamine supply time: 0.3 sec supply, 2.0 sec supply stop

Hexane: 0.3 second supply, 2.0 second supply cut

In this case, the film thickness per cycle is approximately 0.11 nm / cycle. Figure 6 (+ TSA hexane: line (d)) shows a C- doped SiN film as-deposited IR absorption spectrum obtained in the Example 6, in which the main peak of 800 cm from 835 cm ^{-1 - 1} is moved. The SiN absorption peak usually appears in the range of 812 cm ^-1 to 892 cm ^-1 (for example, Si ₃ N ₄ appears at around 830 cm ^-1 ), while the SiC absorption peak is in the range of 900 to 700 cm ^-1 , Lt; ^-1 > cm < ^-1 > The shift of the absorption peak indicates that carbon is present in the deposited film. The deposited dielectric film to which hexane is added has a wet etch rate of 0.03 nm / min in the BHF 130 etchant as shown in Figure 7 (hexane).

Figure 7 compares the wet etch rate of the thermal oxide with the wet etch rate of the deposited films (TSA only, TSA + BEMAS and TSA + hexane).

Table 1 summarizes the above example. By adding the addition precursor, the composition of the deposited film is changed. The added precursor changes performance characteristics such as wet etch rate in etchant.

Table 1: Wet etch rate of various additive precursors Main precursor Addition precursor Supply time
(Main / added) interval RF power WER
(nm / min) Ref.
Trisilylamine (TSA)

none
0.3 sec / 0.3 sec



2.0 seconds


0.07 W / cm ²
4.1 SiN Bis (ethylmethylamino) silane (BEMAS) 0.9 SiCN Diethylsilane (DES) 0.05 SiCN n-hexane 0.03 SiCN

In Example 4-6, the conformity (step coverage: side / top) of the final SiCN film is better around 94% than that of Examples 1 and 2.

Example 7

Table 2 shows changes in wet etching characteristics and film characteristics under various process conditions. The dielectric layer is deposited with TSA and hexane. The nitrogen flow is varied from 0 to 1000 sccm and the hexane feed time is varied from 0.1 to 0.5 seconds. The other process conditions are the same as in Example 6. By changing the process conditions, the film properties of the deposited film and the wet etch rate are changed. In Table 2, the wet etch rate is reduced due to the reduction of the nitrogen flow, and the reflection index is decreased by the increase of the nitrogen flow. It indicates that it is possible to control the composition of the carbon-doped dielectric layer using a combination of chemical and process control parameters.

Figure 8 shows the carbon concentration of the film and the BHF130 wet etch rate as a function of nitrogen flow. The amount of carbon is determined by RBS / HFS measurement and XPS analysis. As the nitrogen flow decreases, the carbon content increases and the wet etch rate decreases. A carbon content of 5 atomic% or more and 10 atomic% or more is preferable in a wet etching resistance with good performance.

Figure 9 shows reflection index and Si / N ratio as a function of nitrogen flow. The amount of silicon and nitrogen (Si / N ratio) is determined by RBS / HFS measurement and XPS analysis. As the nitrogen flow decreases, the reflection index increases and the Si / N ratio increases. Considering the reflection index, a Si / N ratio exceeding 1.0 is preferred.

Figure 10 shows the BHF130 wet etch rate change as the hexane supply time. When the hexane supply time is equal to or longer than that of the first precursor, the wet etch resistance is very high.

Table 2: Wet Etching and Reflective Index Change under Various Process Conditions Main precursor
(Supply time) Addition precursor
(Supply time) interval Nitrogen (sccm) RF power WER (nm / min) R.I.


Trisilylamine (0.3 sec)
















n-hexane (0.3 sec)













2.0 seconds




1000



0.07 W / cm ²




1.02 1.90 800 0.86 1.91 500 0.63 1.92 200 0.33 1.94 100 0.12 1.98 50 0.07 2.04 0 0.03 2.42 n-hexane (0.1 sec) 0 0.25 2.56 n-hexane (0.5 sec) 0 0.02 2.31

An important advantage of at least one of the disclosed embodiments of the present invention is that the etch characteristics of the dielectric layer formed on the semiconductor substrate can be modified or adjusted by using the additive precursor by using process control parameters in combination. The dielectric layer can be formed at relatively low substrate temperatures and the film structure can be controlled to increase productivity on the substrate and extend the applicable substrate form without the occurrence of thermal damage. In addition, the method of at least one embodiment of the present invention can control the thickness, achieve high deposition rates, and form a high conformal structure.

It will be understood by those skilled in the art that many various modifications are possible without departing from the spirit of the present invention. Therefore, the forms of the present invention are for illustrative purposes only and do not limit the scope of the present invention.

3: reaction chamber, 21, 22: gas flow controller,
31: Pulse flow control valve

Claims (19)

A method of forming a conformal dielectric film having silicon-nitrogen (Si-N) bonds on a semiconductor substrate by plasma enhanced chemical vapor deposition (PECVD)
Introducing a reaction gas and a rare gas containing nitrogen gas and hydrogen gas into a reaction space in which the semiconductor substrate is placed;
Applying RF power to the reaction space; And
Introducing a precursor including a silicon gas containing a plurality of pulses each having a duration of less than 5 seconds into the reaction space while introducing the reactive gas and the rare gas and exciting the plasma without interference, Forming a conformal dielectric film having a < RTI ID = 0.0 >
≪ / RTI > wherein the conformal dielectric film has a Si-N bond. The method according to claim 1,
Wherein the precursor containing the hydrogen-containing silicon gas is a silicon-
And the general formula Si _α H _β X _γ, wherein α and the β is a constant, the γ is an integer including 0, wherein X comprises at least one of N, F and C _m H _n, wherein m and the lt; / RTI > wherein n is an integer. The method according to claim 1,
Wherein the precursor containing the hydrogen-containing silicon gas is a silicon-
A method of forming a conformal dielectric film having a Si-N bond, the vaporized upstream of the reaction space being liquid at ambient temperature. delete The method according to claim 1,
The pulse duration,
A method of forming a conformal dielectric film having Si-N bonds that is equal to or shorter than the spacing between pulses. 6. The method of claim 5,
Wherein the precursor containing the hydrogen-containing silicon gas is a silicon-
Wherein the pulses are injected with pulses of a duration of 0.1 to 1.0 seconds at intervals between pulses of 0.1 to 3.0 seconds. The method according to claim 1,
The reaction gas includes,
A mixture of N ₂ and H ₂ , a mixture of NH ₃ and H ₂ , and a nitrogen-boron-hydrogen gas. The method according to claim 1,
The rare-
A mixture of helium and argon or a mixture of helium and krypton. The method according to claim 1,
Wherein the conformal dielectric film comprises a &
A method of forming a conformal dielectric film having Si-N bonds, which is a silicon nitride film. The method according to claim 1,
The hydrogen-containing silicon gas is a silicon-
The first precursor does not have a carbon atom in the molecule,
The precursor,
A method of forming a conformal dielectric film having Si-N bonds, the method further comprising a gas containing a hydrocarbon as a second precursor. 11. The method of claim 10,
Wherein the first precursor and the second precursor comprise a first precursor,
A method of forming a conformal dielectric film having a Si-N bond, which is introduced with pulses of the same timing. 12. The method of claim 11,
Wherein the pulse duration of the second precursor
Wherein the pulse duration of the first precursor is different from the pulse duration of the first precursor. 11. The method of claim 10,
Wherein the conformal dielectric film comprises a &
A method of forming a conformal dielectric film having a Si-N bond, which is a carbon-doped silicon nitride film. A method of forming a dielectric film having Si-N bonds on a semiconductor substrate by plasma enhanced chemical vapor deposition (PECVD)
(I) introducing a reaction gas containing a nitrogen gas and a hydrogen gas and a rare gas into a reaction space in which the semiconductor substrate is placed;
(Ii) applying RF power to the reaction space;
(Iii) introducing a silicon gas containing hydrogen into the reaction space as a first precursor with a plurality of pulses each having a duration of less than 5 seconds while introducing the reactive gas and the rare gas and exciting the plasma without interference; Forming a first dielectric film having Si-N bonds on the substrate; And
(Iv) repeating steps (i) to (iii) to form a second dielectric film having Si-N bonds on the substrate, wherein step (iii) comprises injecting the first precursor with pulses of the same timing Further comprising introducing a second precursor with a pulse to increase the wet etch resistance of the second dielectric film compared to the wet etch resistance of the first dielectric film, wherein the second precursor has a molecular weight greater than that of the first precursor Forming a second dielectric film having Si-N bonds on the substrate, the second dielectric film having more hydrocarbons on the substrate
Wherein the dielectric film has a Si-N bond. 15. The method of claim 14,
The step (iv)
Further comprising: extending the pulse duration of the second precursor relative to the pulse duration of the first precursor. 15. The method of claim 14,
The step (iv)
Further comprising reducing the nitrogen gas flow relative to the nitrogen gas flow for the first dielectric film. A method of forming a dielectric film having Si-N bonds on a semiconductor substrate by plasma enhanced chemical vapor deposition (PECVD)
(I) introducing a reaction gas containing a nitrogen gas and a hydrogen gas and a rare gas into a reaction space in which the semiconductor substrate is placed;
(Ii) applying RF power to the reaction space;
(Iii) injecting the first precursor and the second precursor into the reaction space with a plurality of pulses each having a duration of less than 5 seconds at the same timing while introducing the reactive gas and the rare gas and exciting the plasma without interference, And forming a first dielectric film having Si-N bonds on the substrate, wherein the first precursor is a silicon gas containing hydrogen and the second precursor has more hydrocarbons than the first precursor Forming a first dielectric film having the Si-N bond on the substrate; And
(Iv) repeating steps (i) to (iii) to form a second dielectric film having Si-N bonds on the substrate, wherein step (iii) comprises forming the first and second precursors Further comprising introducing another second precursor with a pulse during the inflow to change the wet etch resistance of the second dielectric film compared to the wet etch resistance of the first dielectric film, Forming a second dielectric film having
Wherein the dielectric film has a Si-N bond. 18. The method of claim 17,
The step (iv)
Further comprising varying the pulse duration of the second precursor relative to the pulse duration of the second precursor. 18. The method of claim 17,
The step (iv)
Further comprising changing the nitrogen gas flow relative to the nitrogen gas flow for the second dielectric film.

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