WO2014094263A1

WO2014094263A1 - Method for utilizing atomic layer deposition to prepare thin film

Info

Publication number: WO2014094263A1
Application number: PCT/CN2012/086984
Authority: WO
Inventors: 解婧; 李超波; 夏洋
Original assignee: 中国科学院微电子研究所
Priority date: 2012-12-18
Filing date: 2012-12-20
Publication date: 2014-06-26
Also published as: CN103866285B; CN103866285A

Abstract

Provided is a method for utilizing atomic layer deposition (ALD) to prepare a thin film, the method comprising: identifying, via a precursor source and a temperature control database, whether the precursor source is a suitable precursor source for both ALD and chemical vapor deposition (CVD), and controlling the temperature of a reaction chamber and a sample according to the identified precursor source. The present invention can inhibit a parasitic CVD reaction in the entire reaction chamber while ensuring the vacuum degree of the chamber, thus the substrate of a prepared film is at the optimum temperature required for ALD, and can fully adsorb the required precursor source while desorbing a byproduct required to be removed, thereby preparing high quality thin film material.

Description

Method for preparing film by atomic layer deposition

Technical field

The present invention relates to the field of atomic layer deposition technology, and in particular to a method for preparing a thin film by atomic layer deposition.

Background technique

Atomic Layer Deposition (ALD) technology is one of the most advanced thin film deposition techniques. Its unique deposition method (monoatomic layer-by-layer deposition) makes the prepared film greatly improved in uniformity, roughness and other properties. Except for the lower growth rate, the other aspects are superior to other deposition methods.

The principle of ALD deposition is similar to that of chemical vapor deposition (CVD). The volatility and stability of the reaction precursor are important factors that must be considered in the reaction process. The difference is that the ALD reaction precursor needs to be able to rapidly react with the substrate material or the surface of the surface of the substrate material in an effective chemical reaction, and achieve saturated adsorption to complete the thin film deposition process; and the CVD reaction temperature is relatively high, such that the precursor The material can be first reacted in the strong chamber first, and then deposited on the substrate to complete the deposition process. These differences result in better step coverage for ALD deposition, less homogeneity of impurities, and lower film formation temperatures.

ALD technology is still being improved. So far, not all precursors suitable for CVD can be applied to ALD technology, but there are also a large number of precursor reaction sources that can be shared by both, such as tris-boron boron. , boron tribromide, diethyl benzene, etc. These commonalities between ALD and CVD allow simultaneous deposition of ALD layers in a suitable temperature range (eg, between 300 ° C and 600 ° C) when both precursor sources are simultaneously introduced into the reaction chamber. And the nucleation reaction of CVD.

In order to maximize the properties and advantages of ALD, it is necessary to suppress the parasitic CVD reaction in the reaction chamber of the atomic layer deposition system, to make the film-forming substrate at the optimal required chemical reaction temperature, and to fully adsorb the desired precursor source. Simultaneous desorption of by-products that need to be removed, thereby preparing the high ALD deposition required Quality film material.

Summary of the invention

The object of the present invention is to provide a method for preparing a thin film by atomic layer deposition, which can suppress the parasitic chemical vapor deposition (CVD) reaction in the reaction chamber while ensuring the vacuum degree of the reaction chamber, thereby preparing high Quality film material.

In order to achieve the above object, the technical solution adopted by the present invention is:

A method for preparing a thin film by atomic layer deposition, comprising the following steps:

Step (1) passing the first precursor source into the reaction chamber of the atomic layer deposition apparatus;

Step (2) detecting the first precursor source and comparing with the precursor source and the temperature regulation database to identify whether the first precursor source is a precursor source suitable for atomic layer deposition and chemical vapor deposition. The precursor source and temperature control database includes a precursor source suitable for atomic layer deposition and chemical vapor deposition, and a temperature range of a sample corresponding to the precursor source for chemical vapor deposition reaction;

Step (3) when it is identified that the first precursor source is a precursor source suitable for both atomic layer deposition and chemical vapor deposition, chemical vapor deposition is performed according to the precursor source and the corresponding precursor source in the temperature control database. The temperature range of the reacted sample, the heating temperature of the sample is controlled, and the first atomic layer deposition is performed on the sample; when the first precursor source is identified as a precursor source only for atomic layer deposition, according to the atom Conventional parameters of the layer deposition reaction are performed on the sample for the first atomic layer deposition;

Step (4) introducing a second precursor source into the reaction chamber;

Step (5) detecting the second precursor source, and comparing with the precursor source and the temperature regulation database, and identifying whether the second precursor source is a precursor for simultaneous atomic layer deposition and chemical vapor deposition Body source

Step (6) when the second precursor source is identified as atomic layer deposition and chemical vapor deposition simultaneously When a precursor source is suitable, the temperature range of the sample subjected to the chemical vapor deposition reaction according to the precursor source and the temperature control database is controlled, and the heating temperature of the sample is regulated, and the second atomic layer deposition is performed on the sample; When it is identified that the second precursor source is a precursor source suitable only for atomic layer deposition, a second atomic layer deposition is performed on the sample according to conventional parameters of the atomic layer deposition reaction; step (7) is adjusted on the sample. The surface reactivity of the deposit is prior to the first pass to the first precursor source;

Step (8) The steps (1) to (7) are cyclically repeated to obtain an atomic layer deposited film.

In the above scheme, the heating temperature of the sample is controlled at 300 ° C - 600 according to different precursor sources.

°C, the heating temperature of the sample is at a temperature suitable for atomic layer deposition, which is lower than the temperature required for chemical vapor deposition.

In the above solution, the precursor source and temperature control database further includes a temperature range of a reaction chamber suitable for a chemical vapor deposition reaction of a precursor source for atomic layer deposition and chemical vapor deposition.

In the above solution, the step (3) further includes: when identifying that the first precursor source is a precursor source suitable for atomic layer deposition and chemical vapor deposition, according to the precursor source and temperature control database The temperature range of the reaction chamber corresponding to the precursor source for the chemical vapor deposition reaction, the temperature of the reaction chamber is regulated, and the first atomic layer deposition is performed on the sample; when the first precursor source is identified as being applicable only For the precursor source of the atomic layer deposition, the first atomic layer deposition is performed on the sample according to the conventional parameters of the atomic layer deposition reaction.

In the above solution, the step (6) further includes: when identifying that the second precursor source is a precursor source suitable for both atomic layer deposition and chemical vapor deposition, according to the precursor source and temperature control database a temperature range of the reaction chamber corresponding to the precursor source for the chemical vapor deposition reaction, adjusting the temperature of the reaction chamber, performing a second atomic layer deposition on the sample; and identifying the second precursor When the source is a precursor source only for atomic layer deposition, a second atomic layer deposition is performed on the sample according to conventional parameters of the atomic layer deposition reaction.

In the above solution, the temperature of the reaction chamber is increased by 5 ° C to 200 ° C on the basis of room temperature, and the temperature of the reaction chamber is lower than the temperature required for the atomic layer and chemical vapor deposition.

In the above scheme, the step (4) and the step (7) are purged before the reaction chamber. Compared with the prior art solution, the technical solution adopted by the present invention has the following beneficial effects: The present invention can control the heating temperature of the reaction chamber and the sample according to different precursor sources, and can realize the vacuum degree of the chamber. Inhibiting the parasitic chemical vapor deposition (CVD) reaction throughout the reaction chamber, so that the film-forming substrate is at the optimum temperature for atomic layer deposition, sufficiently adsorbing the desired precursor source, and desorbing by-products that need to be removed, thereby Preparation of high quality film materials.

DRAWINGS

1 is a process flow diagram of an atomic layer deposition method provided by the present invention;

The technical solutions of the present invention are described in detail below with reference to the accompanying drawings and embodiments.

As shown in FIG. 1, the present invention provides a method for preparing a film by atomic layer deposition, comprising the following steps:

Step 101: Pass a first precursor source into a reaction chamber of the atomic layer deposition apparatus;

Step 102, detecting a first precursor source, and comparing with the precursor source and the temperature regulation database, identifying whether the first precursor source is a precursor source suitable for atomic layer deposition and chemical vapor deposition; the precursor source and The temperature control database includes a precursor source suitable for atomic layer deposition and chemical vapor deposition, and a temperature range of the reaction chamber and sample for the chemical vapor deposition reaction corresponding to the precursor source; Step 103: When identifying that the first precursor source is a precursor source suitable for atomic layer deposition and chemical vapor deposition, the reaction chamber for chemical vapor deposition reaction according to the precursor source and the corresponding precursor source in the temperature control database is identified. And the temperature range of the sample, the temperature of the reaction chamber and the heating temperature of the sample, the first atomic layer deposition on the sample; when the first precursor source is identified as a precursor source only for atomic layer deposition Performing the first atomic layer deposition on the sample according to conventional parameters of the atomic layer deposition reaction;

Step 104, purging the reaction chamber;

Step 105, introducing a second precursor source into the reaction chamber;

Step 106, detecting a second precursor source, and comparing with the precursor source and the temperature regulation database, and identifying whether the second precursor source is a precursor source suitable for atomic layer deposition and chemical vapor deposition; step 107, when When the second precursor source is identified as a precursor source for both atomic layer deposition and chemical vapor deposition, the temperature of the reaction chamber and the sample are chemically vapor deposited according to the precursor source and the corresponding precursor source in the temperature control database. Range, regulating the temperature of the reaction chamber and the heating temperature of the sample, performing a second atomic layer deposition on the sample; when identifying the second precursor source as a precursor source only for atomic layer deposition, according to the atomic layer Conventional parameters of the deposition reaction are performed on the sample for a second atomic layer deposition;

Step 108, purging the reaction chamber;

Step 109, adjusting the surface reactivity of the deposit on the sample to the first time before entering the first precursor source;

Step 110, repeating steps 101 to 109 in a cycle to obtain an atomic layer deposited film.

In this embodiment, the heating temperature of the sample is controlled at 300 ° C ~ 600 ° C according to different precursor sources, and the heating temperature of the sample is at a temperature suitable for atomic layer deposition, which is lower than that suitable for chemical vapor deposition. Temperature is required.

In this embodiment, the temperature of the reaction chamber is increased or decreased by 5 ° C to 200 ° C on the basis of room temperature, and the temperature of the reaction chamber is lower than the temperature required for the atomic layer and chemical vapor deposition. The main purpose of heating the reaction chamber is to maintain the chamber vacuum and the purge rate below the temperature suitable for both ALD and CVD in order to avoid any parasitic reaction products on the chamber, causing air circuit blockage.

The temperature of the reaction chamber in the present invention is constant throughout the preparation of the film, and the temperature is raised or lowered depending on the type of precursor source identified. When the set temperature is reached, the temperature does not change. Different precursor sources have different gasification temperatures and pressures. A precursor source is selected. According to empirical data records, a suitable cavity temperature is selected so that the precursor source is not in the overheated cavity. The body temperature is deposited on the pipe or cavity wall, and the vacuum is not maintained due to the low temperature of the cavity, the purge is insufficient or the purge time is too long.

As shown in Fig. 2, the temperature range 1 indicates a deposition reaction curve lower than the temperature required for ALD and CVD deposition, and the temperature range 2 indicates a deposition reaction curve suitable for the temperature required for ALD deposition, and the temperature range of 3 indicates that it is applicable. A deposition reaction curve for the temperature required for CVD deposition. It can be seen from Fig. 2 that when the reaction temperature is within the temperature range 1, since this temperature is lower than the temperature of any reaction of ALD and CVD, any parasitic reaction product on the cavity can be avoided; and when the reaction temperature is in the temperature range 2 When the temperature range is in the range of 3, and the precursor source is suitable for both ALD and CVD deposition, the precursor source can simultaneously undergo a layer-by-layer deposition reaction of ALD and a nucleation reaction of CVD.

The invention adjusts the temperature of the sample for different precursor sources and regulates the temperature of the reaction chamber in the temperature range where the ALD and CVD deposition reactions coincide, which can promote the ALD reaction to obtain better film quality, and simultaneously CVD. The reaction has a certain inhibitory effect.

Example 1: This embodiment provides an atomic layer deposition method, which specifically includes the following steps:

Step 201: setting a sample stage temperature, and after detecting the set value, placing the sample on the sample stage of the reaction chamber to heat the sample;

Step 202, the first precursor source is introduced into the reaction chamber, and the first precursor source includes trimethylboron, trimethylsulfide, tridecylindium, titanium tetrachloride, boron tribromide, and A precursor reaction source suitable for various ALD and CVD applications such as magnesium oxide and diethylation;

Step 203: Identify a first precursor source through a precursor source and a temperature regulation database and formulate a temperature of the reaction chamber;

Step 204, controlling the temperature of the reaction chamber, and starting the first deposition, the temperature rise range is from 5 ° C to 200 ° C from room temperature;

Step 205, purging the reaction chamber;

Step 206, the second precursor source is introduced into the reaction chamber, and the second precursor source includes water, oxygen, nitrogen, ammonia, and the like;

Step 207: Identify a second precursor source by using a precursor source and a temperature regulation database and formulate a temperature of the reaction chamber;

Step 208, controlling the temperature of the reaction chamber to cool down, and starting the second deposition, the temperature drop range is from 5 ° C to 200 ° C from room temperature;

Step 209, purging the reaction chamber;

Step 210, adjusting the surface reactivity of the sample to the first time before entering the precursor source; Step 211, the above steps are repeated in cycles.

Example 2:

This embodiment provides an atomic layer deposition method, which specifically includes the following steps: Step 301, setting a sample stage temperature, and after detecting the set value, placing the sample on the sample stage of the reaction chamber to heat the sample;

Step 302, the first precursor source is introduced into the reaction chamber, and the first precursor source includes trimethylboron, tridecyl aluminum, tridecyl indium, titanium tetrachloride, boron tribromide, and A precursor reaction source suitable for various ALD and CVD applications such as magnesium oxide and diethylation;

Step 303: Identify a first precursor source through a precursor source and a temperature regulation database and formulate a temperature of the reaction chamber;

Step 304, controlling the temperature of the reaction chamber to cool down, and starting the first deposition, the temperature range of the cooling is from 5 ° C to 200 ° C ;

Step 305, purging the reaction chamber;

Step 306, the second precursor source is introduced into the reaction chamber, and the second precursor source includes water, oxygen, nitrogen, ammonia, and the like;

Step 307: Identify a second precursor source by using a precursor source and a temperature regulation database and formulate a temperature of the reaction chamber;

Step 308, controlling the temperature of the reaction chamber, and starting a second deposition, the temperature rise range is from 5 ° C to 200 ° C ;

Step 309, purging the reaction chamber;

Step 310, adjusting the surface reactivity of the sample to the first time before entering the precursor source; Step 311, the above steps are repeated in cycles.

According to the invention, the heating temperature of the reaction chamber and the sample is regulated according to different precursor sources, and the parasitic chemical vapor deposition (CVD) reaction of the reaction chamber can be suppressed under the condition of ensuring the vacuum degree of the chamber, so that the film formation substrate is formed. At the optimum temperature required for atomic layer deposition, fully adsorb the desired precursor source, When the desorption is carried out, it is necessary to exclude by-products, thereby preparing a high quality film material.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

claims

1. A method for preparing thin films by atomic layer deposition, which is characterized by including the following steps: Step (1) Passing the first precursor source into the reaction chamber of the atomic layer deposition equipment;

Step (2) Detect the first precursor source and compare it with the precursor source and temperature control database to identify whether the first precursor source is a precursor source suitable for both atomic layer deposition and chemical vapor deposition. ; The precursor source and temperature control database includes precursor sources suitable for atomic layer deposition and chemical vapor deposition, and the temperature range of samples for chemical vapor deposition reactions corresponding to the precursor sources;

Step (3) When it is identified that the first precursor source is a precursor source suitable for both atomic layer deposition and chemical vapor deposition, perform chemical vapor deposition according to the precursor source and the corresponding precursor source in the temperature control database. The temperature range of the sample to be reacted, the heating temperature of the sample is controlled, and the first atomic layer deposition is performed on the sample; when the first precursor source is identified as a precursor source only suitable for atomic layer deposition, according to the atoms The conventional parameters of the layer deposition reaction are used to perform the first atomic layer deposition on the sample; Step (4) Pass the second precursor source into the reaction chamber;

Step (5) Detect the second precursor source and compare it with the precursor source and temperature control database to identify whether the second precursor source is a precursor suitable for both atomic layer deposition and chemical vapor deposition. body source;

Step (6) When it is identified that the second precursor source is a precursor source suitable for both atomic layer deposition and chemical vapor deposition, perform chemical vapor deposition according to the precursor source and the corresponding precursor source in the temperature control database. The temperature range of the sample to be reacted, the heating temperature of the sample is controlled, and the second atomic layer deposition is performed on the sample; when the second precursor source is identified as a precursor source only suitable for atomic layer deposition, according to the atoms Conventional parameters for layer deposition reactions A second atomic layer deposition was performed on the sample; Step (7) Adjust the surface reactivity of the sediment on the sample before introducing the first precursor source for the first time;

Step (8) repeats step (1) to step (7) cyclically to obtain an atomic layer deposition film.

2. The method of preparing thin films by atomic layer deposition as claimed in claim 1, wherein the heating temperature of the sample is controlled at 300°C ~ 600°C according to different precursor sources. At the temperature required for atomic layer deposition, lower than the temperature required for chemical vapor deposition.

3. The method of preparing thin films by atomic layer deposition as claimed in claim 1, wherein the precursor source and temperature control database further include a precursor source suitable for atomic layer deposition and chemical vapor deposition for chemical vapor deposition. The temperature range of the reaction chamber for the reaction.

4. The method of preparing a thin film by atomic layer deposition as claimed in claim 3, wherein the step (3) further includes: when it is identified that the first precursor source is atomic layer deposition and chemical vapor deposition When the precursor source is applicable at the same time, according to the precursor source and the temperature range of the reaction chamber for the chemical vapor deposition reaction corresponding to the precursor source in the temperature control database, the temperature of the reaction chamber is adjusted, and the first time is performed on the sample. Atomic layer deposition; When the first precursor source is identified as a precursor source suitable only for atomic layer deposition, perform the first atomic layer deposition on the sample according to the conventional parameters of the atomic layer deposition reaction.

5. The method of preparing a thin film by atomic layer deposition as claimed in claim 3, wherein the step (6) further includes: when it is identified that the second precursor source is atomic layer deposition and chemical vapor deposition When the precursor source is applicable at the same time, the temperature of the reaction chamber is adjusted according to the temperature range of the reaction chamber in which the chemical vapor deposition reaction is performed for the corresponding precursor source in the precursor source and the temperature control database, and the second time is performed on the sample. Atomic layer deposition; When the second precursor source is identified as a precursor source that is only suitable for atomic layer deposition, perform the second atomic layer on the sample according to the conventional parameters of the atomic layer deposition reaction. layer deposition.

6. The method for preparing thin films by atomic layer deposition as claimed in claim 4 or 5, characterized in that the temperature of the reaction chamber is increased or decreased by 5°C to 200°C based on room temperature. The temperature of the reaction chamber is lower than that required for atomic layer and chemical vapor deposition.

7. The method of preparing a thin film by atomic layer deposition as claimed in claim 1, wherein the reaction chamber is purged before performing steps (4) and (7).