JP2003201560A - Sputtering target and manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sputtering target by which the generation of particles and dust during sputtering operation can be effectively reduced and film- deposition operation can be continued with stability by suppression of abnormal electric discharge and, further, constituents are uniformly dispersed and resultantly a wiring film, etc., having excellent uniformity (in-plane isotropy) of characteristics, such as oxidation resistance and thickness, can be deposited and also to provide its manufacturing method. <P>SOLUTION: This sputtering target has a composition containing 5 to 60 atomic % aluminum and having the balance composed essentially of titanium. When this sputtering target is subjected to Al mapping by EPMA (Electron Probe Micro Analyzer) analysis, the frequency of existence of a zone of Al segregation, in which the diameter of a minimum circle which encloses stringing parts having ≥400 number of counts of sensitivity in 200 μm<SP>2</SP>measurement area is ≥2 μm, is made to ≤5 pieces in the above measurement area. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering target and a method for manufacturing the same, and more particularly, when a thin film as an electrode or a wiring material of a semiconductor device is formed by sputtering the target, the generation of particles during the sputtering operation is effective. It is possible to reduce abnormally, suppress abnormal discharge and continue the film formation operation stably.
Further, the present invention relates to a sputtering target capable of improving the oxidation resistance of a semiconductor device to enhance its durability and significantly improving the product yield, and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, the construction technology of various semiconductor devices used in the fields of electronics such as LSIs, liquid crystals, and PDPs, and magnetic recording has made remarkable progress, and has achieved high capacity, high output, and high integration. The tendency to change is further developing. For example, in DRAM, gigabyte-class products are already in the market. On the other hand, a ferroelectric RAM (FeRAM) or T using a ferroelectric thin film as a capacitor
Development of a memory that replaces a conventional DRAM, such as an MRAM using an MR element, has been promoted, and a part of the memory has already been commercialized.

These semiconductor devices have a multi-layered structure composed of a large number of thin films, and the interfacial reactivity, mutual diffusivity, adhesion of the thin films, and the like in different kinds of thin films are very important points for determining device characteristics. Become.

Recently, in place of the polysilicon electrode which has been used conventionally, an electrode made of a noble metal-based material such as Pt, Ir, Ru or a noble metal oxide-based material such as IrOx, PtOx, RuOx is used, and BaSrTiOx,
A structure in which a capacitor film using a ferroelectric thin film made of PbZrTiOx or the like is sandwiched between a pair of upper and lower electrodes is generally adopted. The processing temperature for forming the capacitor thin film is extremely high in the semiconductor manufacturing process, and a high processing temperature of 600 ° C. or higher is required. Also,
Since it is necessary to form an oxide, the film forming process is often performed in an oxygen atmosphere.

[0005]

In the process carried out under the high temperature condition and in the oxygen atmosphere as described above, oxygen contained in the ferroelectric oxide diffuses toward the lower electrode portion to form an electrode. There is a problem that a noble metal oxide is easily formed at the interface with the capacitor and peeling is likely to occur due to volume expansion of the oxide. Therefore, a measure is taken to avoid the above problem by forming a diffusion prevention layer between the electrode and the capacitor.

As a material for forming the diffusion preventing layer,
In general, TiN and TaN were used in many cases, but TiAlN is currently drawing attention. This Ti
The AlN diffusion prevention layer is thermally and chemically stable and has excellent oxidation resistance. At present, in order to stabilize the capacitor film, the processing temperature at the time of forming the thin film is shifting to a higher temperature side, and reaches about 700 ° C.

However, when the Al content is 60 at% or more, on the contrary, the oxidation resistance is easily deteriorated, and a phenomenon occurs in which O ₂ and other mobile ions easily pass through the diffusion prevention layer. From this result, the Al content is limited to the range up to 60 at%.

On the other hand, impurities are an important factor as an item generally required for a sputtering target for forming a film used for semiconductors and liquid crystals. For example,
Radiation elements such as U and Th adversely affect the reliability of MOS devices, and alkali metals such as Na and K
It is mentioned as a factor that causes deterioration of the interface characteristics of the MOS device.

As a method for forming the TiAlN diffusion prevention layer, it is general to use a sputtering target made of a Ti--Al alloy and a reactive sputtering method using a mixed gas of Ar and N ₂ .

The T used in this reactive sputtering method
The i-Al alloy sputtering target is manufactured through the following steps in consideration of the influence of the above-described composition and impurities. That is, after producing an ingot of a predetermined composition using the melting method, in order to satisfy the fine grain size required for the target, hot sputtering including forging and rolling including appropriate heat treatment is applied to the sputtering target. Is generally used.

However, the Al content is 30 to 60a.
In the target composition range of t%, high hardness intermetallic compounds such as Ti ₃ Al and TiAl ₃ are easily deposited, which causes a problem that the plastic working of the target material becomes difficult.

On the other hand, from the viewpoint of preventing the target from being contaminated with impurities, a crucible that matches a predetermined target size is prepared, a molten ingot is prepared in a state where impurities are blocked, and the ingot is sliced,
It is also possible to produce a target of a predetermined size.

However, the crystal grain size of the target made of the ingot prepared by the above-mentioned melting method is as large as several mm, and the variation of the crystal grain size is extremely large. It is already known that the size of this crystal grain size has a great influence on the generation of particles and dust during sputtering, which is a major factor causing defects during the formation of DRAM, TFT elements, etc., and increases the manufacturing yield of semiconductor devices. There is a problem that lowers it. In addition, dust and particles taken in the wiring film also cause electromigration and stress migration.

Further, it is known that variations in the crystal grain size of the target adversely affect the film thickness uniformity of the thin film obtained by sputtering. Judging from these viewpoints, the above-described method of producing a target by preparing an ingot by a melting method, then performing hot plastic working, and further performing recrystallization treatment is not suitable.

On the other hand, a manufacturing method based on the sintering method is also widely adopted from the viewpoint of making the particle diameter of the target appropriate.
This manufacturing method is less restricted by the target size than a process using a melting method restricted by the target size, and is a method suitable for making the target composition uniform.

However, from the viewpoint of impurities, when the raw material powder mixture is produced, there is contamination by a high concentration of impurity elements of several hundred to several thousand ppm, and the surface area of the raw material powder is extremely large. There is a problem that a large amount of components are adsorbed and mixed into the target. Even if a target is prepared by sintering using such a raw material powder, it is not possible to reduce gas components and other impurity components, and it is unsuitable for high-purity targets.

Further, the dispersion state of the Ti component and the Al component in the target structure has a great influence on the film characteristics. This is the melting point of Ti and Al (Ti: 1675 ° C., Al:
660 ° C.), and when sputtering is performed using a target in which Ti and Al components are segregated, the heat resistance and oxidation resistance of the film are partially deteriorated. There was also. As a result, there are serious problems such as poor characteristics of electronic devices, deterioration of durability and reliability, and a significant decrease in manufacturing yield of semiconductor products.

The present invention has been made to solve the above-mentioned conventional problems, and particularly when a thin film as an electrode or wiring material of a semiconductor device is formed by sputtering, particles and dust are generated during the sputtering operation. Can be effectively reduced, abnormal discharge can be suppressed, and stable film formation operation can be continued. Furthermore, the constituent components are dispersed extremely uniformly, and the characteristics such as oxidation resistance and thickness are uniform. It is possible to efficiently form a wiring film, etc. with excellent properties (in-plane uniformity), improve the oxidation resistance of the semiconductor device, improve durability, and significantly improve the product yield. An object of the present invention is to provide a sputtering target and a manufacturing method thereof.

[0019]

[Means for Solving the Problems] In order to achieve the above-mentioned objects, the present inventors have made various investigations, particularly for a high-purity Ti--Al alloy-based sputtering target, and as a result, have obtained the following findings. It was That is, the mother alloy prepared by the vacuum melting method was made into an alloy powder having a predetermined particle diameter by the rotating electrode method, and when this was sintered, segregation was small and the constituent components were uniformly dispersed, and the generation of particles and abnormal discharge occurred. We found that a small number of targets were obtained for the first time, and when sputtering was performed using this target, it was possible to efficiently form a wiring film, etc. with excellent in-plane uniformity such as oxidation resistance, adhesion, and film thickness. Obtained. The present invention has been completed based on the above findings.

That is, the sputtering target according to the present invention is a sputtering target which contains aluminum (Al) in an amount of 5 to 60 atomic% and the remaining component is substantially titanium (Ti).
ron Probe Micro Analyzer)
When Al mapping by analysis is carried out, 200
The count number of measurement sensitivity is 400 within the measurement area of square μm.
It is characterized in that the number of Al segregated portions in which the diameter of the smallest circle surrounding the continuous portion is 2 μm or more is 5 or less in the measurement region.

Further, in the above sputtering target, when the mapping of titanium by the EPMA analysis is performed, the diameter of the smallest circle that surrounds the continuous portion where the count number of the measurement sensitivity is 3500 or more in the measurement area of 200 μm square is It is preferable that the number of Ti segregated portions having a size of 2 μm or more is 5 or less in the measurement region.

Further, in the above sputtering target, when Al mapping was performed by the EPMA analysis, the measurement area of 200 μm square was divided into four equal areas.
In each of the divided regions, when the area ratio of the Al segregated portion whose measurement sensitivity count number is 400 or more is measured, the variation in the area ratio in each divided region is preferably within 30%.

Further, in the above sputtering target, when the Ti mapping by the EPMA analysis was carried out, the measurement area of 200 μm square was divided into four equal areas, and the count number of the measurement sensitivity was 4700 or more. When the area ratio of a certain Ti segregated portion is measured, it is preferable that the variation of the area ratio in each divided region is within 30%.

Further, in the above sputtering target, the maximum diameter of the Al segregated portion is preferably 30 μm or less, and the maximum diameter of the Ti segregated portion is φ.
It is preferably 30 μm or less.

Further, the method for producing a sputtering target according to the present invention is a sputtering target which contains aluminum in an amount of 5 to 60 atomic% and the balance of which is substantially titanium, and when Al mapping is performed by EPMA analysis. , Manufacture of a sputtering target in which there are 5 or less Al segregated portions having a diameter of a minimum circle of 2 μm or more surrounding a continuous portion having a count number of measurement sensitivity of 400 or more in a measurement region of 200 μm square in the measurement region. In the method, the aluminum content is 5 to 60
A step of preparing a raw material body by blending an aluminum material and a titanium material so as to be atomic%; a step of preparing a Ti-Al master alloy by melting and solidifying the raw material body by a vacuum melting method; The Ti-Al mother alloy was melt-dispersed by the rotating electrode method so that the aluminum content was 5-60.
a step of preparing a Ti-Al alloy powder containing at% and having a particle diameter of 500 µm or less, and a step of forming and sintering the obtained Ti-Al alloy powder to prepare a Ti-Al alloy sintered body, and using it as a sputtering target. And is provided.

In the method of manufacturing a sputtering target, the vacuum melting method is a vacuum arc melting method,
It is preferably either a cold crucible melting method or an electron beam melting method (EB melting method).

Further, in the above method for producing a sputtering target, the sintering is based on any one of a hot press (HP) sintering method, a hot isostatic pressing (HIP) method and a plasma discharge sintering method. Is preferably carried out.

The sputtering target according to the present invention focuses on the dispersibility of Ti and Al,
The color mapping result by the EPMA of the target tissue is used as a measure for defining the quality of the dispersibility.

EPMA (Electron Probe)
Micro Analyzer: X-ray microanalyzer) is widely used as a means for quantifying segregation components and identifying nonmetallic inclusions based on the following measurement principle. That is, when the surface of a substance is irradiated with a high-speed electron beam flux, various kinds of radiation are emitted, and the characteristic X-rays therein are peculiar to the substance irradiated, and the elements present in a minute portion of about several μm when the wavelength is measured. The quantitative analysis of

The sputtering target of the present invention contains aluminum (Al) in an amount of 5 to 60 atomic% (at).
%) And the balance component is substantially titanium (Ti). When the Al content is less than 5 atomic% (at%),
It is difficult to improve the oxidation resistance of the film obtained by sputtering this target. On the other hand, when the Al content exceeds 60 atomic% (at%), the oxidation resistance of the thin film obtained by sputtering this target is deteriorated, and when it is used as a diffusion prevention layer,
₂ and other mobile ions easily pass through the thin film, impairing the function as a barrier metal layer.

Regarding the dispersibility of Al, when Al mapping is performed by EPMA analysis on the target surface structure, a continuous portion where the count number of measurement sensitivity is 400 or more is measured within a measurement area of 200 μm square. The number of existing Al segregated portions having the diameter of the smallest surrounding circle of 2 μm or more is defined to be 5 or less in the above measurement region.

Specifically, an EPMA device (JEOL J
In the Al mapping result by the analysis using XA-8600M), the number of Al segregated portions defined as described above is set to 5 or less in the measurement region.

If the number of Al segregated portions present in the above measurement region exceeds 5, uniform film characteristics cannot be obtained. Therefore, the number of Al segregated portions is specified to be 5 or less,
The number is preferably 3 or less, more preferably 2 or less.

Regarding the dispersibility of Ti, the above EPM
When titanium (Ti) is mapped by A analysis, a Ti segregation part having a minimum circle diameter of 2 μm or more that surrounds a continuous portion having a measurement sensitivity count of 3500 or more in a 200 μm square measurement region is used. It is preferable that the number of existence is 5 or less in the measurement region.

Similar to the Al segregated portion, if the number of Ti segregated portions present in the measurement region exceeds 5, uniform film characteristics cannot be obtained. Therefore, the number of Ti segregated portions is defined to be 5 or less, preferably 3 or less, and further 2
Less than or equal to is desirable.

Further, when Al or Ti is mapped by the EPMA analysis, the Al segregation in which the count number of the measurement sensitivity is 400 or more in each divided area obtained by dividing the measurement area of 200 μm square into four equal areas. When measuring the area ratio of the parts or the area ratio of the Ti segregation part where the count number of measurement sensitivity is 4700 or more, it is preferable that the variation of each area ratio in each divided region is within 30%.

The variation in the Al segregated portion or the Ti segregated portion is calculated by the following equation (1) from the maximum value and the minimum value of the area ratio in each of the four divided regions.

[0038]

[Equation 1] If the value of the variation in the segregation portion exceeds 30%, uniform film characteristics cannot be obtained in the same manner as described above, and the manufacturing yield of semiconductor products using thin films decreases. In particular, in order to achieve in-plane uniformity of the thin film and form a uniform thin film even on a large-diameter wafer, it is more preferable that the segregation portion has a variation of 15% or less.

Further, in the above sputtering target, the maximum diameter of the Al segregated portion is preferably 30 μm or less, and the maximum diameter of the Ti segregated portion is 30.
It is preferably μm or less.

The maximum diameter of the Al segregated portion or the Ti segregated portion is
The reason why the maximum diameter is preferably 30 μm or less is 3
If there is a coarse segregation portion exceeding 0 μm, it is difficult to obtain uniform film characteristics, but the maximum diameter of the segregation portion is 30 μm.
This is because when it is m or less, the film characteristics are not significantly affected.

In the target of the present invention, a composition containing titanium (Ti) as a main component is often adopted, but titanium mainly forms a compound phase of Ti ₃ Al in the target structure, and thus EPMA is used. Even if the mapping is performed, the sensitivity for detecting the state of existence of Ti alone is low. Therefore, it is possible to estimate the dispersion state of Ti from the result of mapping the Al component.

In any case, when the film formation is performed using the target having the segregated portion of Al or Ti component as described above, the problem that the heat resistance and the oxidation resistance of the thin film are deteriorated becomes remarkable. . Therefore, the variation in the area ratio of the Ti segregated portion is preferably 30% or less, and more preferably 15% or less like Al.

The method for producing a sputtering target made of a Ti--Al alloy of the present invention, except that specific raw material composition, purity, grain size, plastic working conditions and heat treatment conditions are satisfied,
The process is not particularly limited and is performed by the following process, for example.

First, needle titanium having a purity of about 4N (99.99%) is melted by electron beam (EB). At this time, EB
A high-purity Ti material is prepared by maintaining the degree of vacuum in the melting chamber at 1 × 10 ⁻⁵ Pa and further performing a melting operation at least three times repeatedly to carry out purification.

The above melting operation was performed at a vacuum degree of 1 × 10.
^-Even if it is carried out in a chamber exceeding ² Pa, the effect of removing impurities and the effect of degassing cannot be sufficiently obtained, and the target will contain a large amount of residual gas components and impurities, and the amount of particles generated during sputtering. And the film characteristics also deteriorate. Therefore, the degree of vacuum during melting is set to 1 × 10 ⁻² Pa or less, but 1 ×
It is desirable that the vacuum is as high as 10 ⁻³ Pa or less.

On the other hand, Al can be used as it is as long as it has a purity of 4N or more, but when the raw material has a low purity, the refining operation is repeated at least three times by using the zone refining method to obtain the purity. A high purity Al material of 4N to 5N is obtained.

Next, the Ti material and Al prepared as described above
Ti-Al is mixed with the material at a predetermined ratio, and the resulting raw material is melted and solidified by applying a vacuum melting method such as electron beam melting method, vacuum arc melting, cold crucible melting method, etc.
Make a master alloy.

Further, with respect to the obtained mother alloy, a rotating electrode method (Plasma Rotating Electror) was used.
by performing a melt dispersion treatment using an OD process (P-REP) to produce a Ti—Al alloy powder having an Al content of 5 to 60 at% and a particle size of 500 μm or less.

At this time, if the grain size of the Ti--Al alloy powder becomes coarse so as to exceed 500 μm, the target sintering having a predetermined high density of 99% or more can be achieved even if the sintering conditions are changed over a wide range. I can't get a body. Moreover, the segregation amount of Al or Ti as a constituent component increases, and the variation in the area ratio of the segregation portion also increases in the entire target.

Next, the Ti--Al alloy powder produced as described above is heated at a temperature of 1000 to 1500 ° C. for 3 hours or more in a vacuum of 1 × 10 ^-2 Pa or less, or at a pressure of 1.
By performing pressure hot press sintering at 9.6 MPa or more, hot isostatic pressing (HIP) treatment, or plasma discharge sintering, Ti-A
An l-alloy sintered body is produced.

In the above-mentioned sintering process, when the treatment is carried out at a temperature of less than 1000 ° C. or the heat treatment is conducted for less than 3 hours, only a sintered body having a low density and containing a large amount of gas components is obtained. If not obtained, the film characteristics obtained by sputtering are deteriorated. On the other hand, when the treatment is performed at a temperature of 1500 ° C. or higher, the crystal grains of the target structure grow abnormally and the average crystal grain size of the sintered body becomes coarse, and
The variation also becomes large.

The Ti—Al alloy sintered body thus obtained is machined to a predetermined size to obtain the sputtering target according to the present invention.

According to the sputtering target and the manufacturing method thereof having the above-described structure, the mother alloy prepared by the vacuum melting method is made into the alloy powder having a predetermined particle diameter by the rotating electrode method, and this is sintered to form the target. Therefore, the segregation is small and the constituent components are uniformly dispersed, so that a target in which particles and abnormal discharge are less generated can be obtained. Also, when performing sputtering using this target,
A wiring film or the like having excellent in-plane uniformity such as oxidation resistance, adhesion, and film thickness can be efficiently formed.

[0054]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments and effects of the present invention will be described more specifically with reference to the following examples and comparative examples.

[0055]

Example 1 First, T with a purity of 4N5 (99.995%)
i material and Al material with a purity of 4N (99.99%) are prepared, and T
It was weighed and mixed so as to have a composition of i-30 at% Al. The mixture of the Ti material and the Al material was set in a vacuum arc melting apparatus, and the inside of the chamber of the apparatus was 5.0 × 10 ^−3.
After exhausting to Pa, arc melting is performed and the diameter is 80m.
An ingot having m × 100 mm length was produced.

The obtained ingot was machined to a diameter of 7
The electrode material having a length of 0 mm and a length of 100 mm was used, and the obtained electrode material was used to perform a melt dispersion treatment based on the plasma rotary electrode method (P-REP) at a rotation speed of 12000 rpm.
An i-Al alloy powder was produced. The average particle diameter of the obtained Ti-Al alloy powder was 100 μm. After filling the alloy powder with a carbon mold having a diameter of 130 mm, the alloy powder was loaded into a pressure hot press machine, and the temperature was 10 ° C./min in vacuum.
After heating to a temperature of 1200 ° C at a heating rate of
Sintering was performed under the condition of 4.5 MPa for 5 hours.

The obtained sintered body was machined to have a diameter of 12
7 mm × 5 mm thick disk-shaped molding, and an EPMA device (JXOL-JXA-86 manufactured by JEOL was used for the disk-shaped sintered body.
00M) to obtain a color mapping of the Ti component and the Al component in the measurement area of 200 μm square. As a result, the number of Ti segregated portions having a minimum circle diameter of 2 μm or more surrounding a continuous portion having a measurement sensitivity count number of 3500 or more was 3, and the maximum diameter of the Ti segregated portion was 10 μm. .

Similarly, with respect to Al, the number of existing Al segregated portions having a diameter of a minimum circle of 2 μm or more surrounding a continuous portion having a count number of measurement sensitivity of 400 or more is 1
The maximum diameter of the Al segregated portion was 8 μm.

Further, the measurement area of 200 μm square is 4
The area ratio of the segregated portion is measured for each component of Ti and Al, and the variation is calculated as above [(maximum value-minimum value) / (maximum value + minimum value)] × 100 (%).
It was calculated by the equation (1). As a result, the variation in the area ratio of the Ti segregated portion was 3%, while the variation in the area ratio of the Al segregated portion was 5%. From the above facts, it was found that the segregation of the constituent components of the target was sufficiently suppressed.

The Ti--Al sintered body thus prepared and A
The 1-backing plate and the backing plate were integrally joined by a solder joining method to obtain a Ti-Al sputtering target according to Example 1.

Using the TiAl sputtering target thus obtained, a substrate-target distance was set on an 8-inch Si wafer substrate whose surface was thermally oxidized, using a magnetron sputtering device (ULVAC: SH-550). = 150 mm, back pressure: 1 × 10 ⁻⁵ Pa,
Under the conditions of output DC: 2 kW, Ar flow rate: 10 sccm, N ₂ gas flow rate: 20 sccm, and sputtering time: 10 min, a TiAlN film with a thickness of 1000 Å was sputtered, and the number of particles with a diameter of 0.2 μm or more mixed in the thin film. Was measured. Regarding particles,
A particle measuring instrument (WM3) was used.

Further, in order to evaluate the in-plane uniformity of the thin film formed on the entire wafer, thin film samples were taken from 17 sites shown in FIG. That is, the center of the circular thin film (site 1) and the center of the four straight lines that evenly divide the circumference through the center from the center to the outer circumference have a radius of 9
0% position (sites 2-9) and 50% of radius from center
The total of 17 positions (parts 10 to 17) were set as the thin film sample collection positions.

Then, for each thin film sample, the film thickness was measured by using a film thickness measuring device (Alpha-Step 200), and the variation in the film thickness was determined by [(maximum value-minimum value ) / (Maximum value + minimum value) ×
100 (%)] is calculated by the equation (1),
The in-plane uniformity of film thickness was evaluated.

As a result, the number of particles having a diameter of 0.2 μm or more mixed in was 8 p / w, and the variation in film thickness was 10 μm.
%, And it was possible to stably form a high quality thin film.

Further, in order to evaluate the oxidation resistance of the formed TiAlN film, the amount of oxide produced after the W film was further formed and the heat treatment was investigated as follows. That is, a W target was attached to the same sputtering apparatus, the distance between the substrate and the target was 150 mm, and the back pressure was 1 × 10 ^−5.
Pa, output: DC 2 kW, Ar pressure: 0.5 Pa, sputtering time: 5 min, W on the TiAlN film
A film was formed at 1000Å. After that, the film-formed wafer was subjected to vacuum heat treatment at a vacuum degree of 1 × 10 ⁻² Pa and a temperature of 600 ° C. for 3 hours, and then a profile measurement was performed using an X-ray diffractometer of a scientific instrument to obtain a W oxide. Formation state of X
The oxidation resistance was evaluated by investigating based on the line strength. As a result, the X-ray peak intensity of the W oxide was 0, and it was confirmed that sufficient oxidation resistance was obtained.

[0066]

Example 2 A Ti material having a purity of 4N5 (99.995%) and an Al material having a purity of 4N were prepared and weighed so as to have a composition composition of Ti-40 at% Al. The Ti material and Al material were set in a cold crucible melting device, and 7 × 10
After exhausting the inside of the apparatus until a vacuum degree of ^-3 Pa is obtained, a melting process is performed, and a diameter of 80 mm x a length of 100 mm
The ingot of was produced. The obtained ingot is machined into an electrode material having a diameter of 70 mm and a length of 100 mm, and the obtained electrode material is subjected to a dissolution / dispersion treatment based on a plasma rotating electrode method (P-REP) at a rotation speed of 10000 rpm. Then, a Ti-Al alloy powder was produced. The average particle size of the alloy powder was 200 μm. The alloy powder was filled in a carbon mold having a diameter of 130 mm, placed in a pressure hot press machine, heated in vacuum to a temperature of 1300 ° C. at a temperature rising rate of 10 ° C./min, and then 24.5 MPa.
Sintering was performed for 4 hours under the pressure conditions of.

The obtained sintered body was machined to a diameter of 127
After forming into a disk shape with a thickness of 5 mm and a thickness of 5 mm, analysis was performed using the same EPMA device as described above to obtain color mapping of Ti and Al components in a measurement area of 200 μm square.

As a result, the count number of measurement sensitivity is 350.
The diameter of the smallest circle that encloses a continuous portion that is 0 or more is 2 μm.
The number of the Ti segregated portions as described above was two, and the maximum diameter of the Ti segregated portion was 18 μm.

Similarly, with respect to Al, the number of Al segregated portions having a minimum circle diameter of 2 μm or more surrounding a continuous portion having a measurement sensitivity count number of 400 or more is 2
The maximum diameter of the Al segregated portion was 27 μm.

Further, the above measurement area was divided into four, the area ratios of the Ti segregated portion and the Al segregated portion were measured, and the variation thereof was calculated based on the above equation (1). As a result, the variation in the area ratio of the Ti segregated portion was 10%,
The variation in the area ratio of the Al segregated portion was 19%. From the above facts, it was found that the segregation of the constituent components of the target was sufficiently suppressed.

The Ti--Al sintered body thus prepared and A
The 1-backing plate and the backing plate were integrally joined by a solder joining method to obtain a Ti-Al sputtering target according to Example 2.

A Ti-Al sputtering target thus obtained was used to heat-oxidize the surface of the Si wafer, and the same magnetron sputtering apparatus as described above was used. The distance between the substrate and the target was 150 mm, and the back pressure was: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate:
TiA with a film thickness of 1000 Å under the conditions of 10 sccm, N ₂ gas flow rate: 20 sccm, and sputtering time: 10 min.
The 1N film was sputtered and the number of particles having a diameter of 0.2 μm or more mixed therein was investigated.

Further, thin film samples were taken from the 17 sites shown in FIG. 1 and the film thickness was measured using a film thickness measuring device, and the variation of the film thickness was determined by the above [(maximum value-minimum value)].
/ (Maximum value + minimum value) × 100 (%)], and the in-plane uniformity of the film thickness was evaluated. As a result, the number of particles having a diameter of 0.2 μm or more mixed in was 14 p / w, the variation in film thickness was 8%, and stable film formation operation could be realized.

Further, a W target was attached to the same sputtering apparatus, the substrate-target distance = 150 mm, back pressure: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar pressure:
Ti under the conditions of 0.5 Pa and sputter time: 5 min
A W film was formed on the AlN film at 1000 Å. Thereafter, the film-formed wafer is vacuumed at a temperature of 1 × 10 ⁻² Pa and a temperature of 6
After performing vacuum heat treatment at 00 ° C. for 3 hours, profile measurement was performed with an X-ray diffractometer of a scientific instrument to investigate whether or not an oxide of W was formed to evaluate the oxidation resistance of the thin film. . As a result, it was confirmed that the peak intensity of the W oxide was 100, and although it was slightly oxidized, it did not affect the device characteristics.

[0075]

Example 3 A Ti material having a purity of 4N5 and an Al material having a purity of 4N were prepared and weighed so as to have a composition of Ti-36 at% Al. The Ti material and the Al material were set in an arc melting apparatus, and the inside of the apparatus was evacuated to 5.0 × 10 ⁻³ Pa, and then the melting operation was performed to obtain a diameter of 80 mm and a length of 100 mm.
The ingot of was produced. The obtained ingot is machined into an electrode material having a diameter of 70 mm and a length of 100 mm,
Using the obtained electrode material, a plasma dispersion electrode method (P-REP) dissolution / dispersion treatment was performed at a rotation speed of 11000 rpm to produce a Ti-Al alloy powder. The average particle size of the alloy powder was 150 μm. The alloy powder was filled in a carbon mold having a diameter of 130 mm, heated to a temperature of 1250 ° C. in a vacuum at a temperature rising rate of 10 ° C./min using a pressure hot press machine, and the pressure of 24.5 MPa was applied for 5 minutes. Sintered for hours.

The resulting sintered body was machined to a diameter of 127
mm-thick 5 mm disk-shaped, EP similar to the above
Analysis was performed using a MA apparatus to obtain color mapping of Ti and Al components in a measurement area of 200 μm square. As a result, the number of Ti segregated portions having a minimum circle diameter of 2 μm or more surrounding a continuous portion having a measurement sensitivity count number of 3500 or more was 5, and the maximum diameter of the Ti segregated portion was 21 μm. .

Similarly, with respect to Al, the number of Al segregated portions having a diameter of a minimum circle of 2 μm or more surrounding a continuous portion with a count number of measurement sensitivity of 400 or more is 3 or more.
The maximum diameter of the Al segregated portion was 10 μm.

Further, the measurement area is divided into four, and Ti, A
l The area ratio of each segregated portion was measured, and the variation was calculated as [(maximum value−minimum value) / (maximum value + minimum value) ×
100 (%)] was calculated based on the equation (1). As a result, the variation in the area ratio of the Ti segregated portion was 17%, and the variation in the area ratio of the Al segregated portion was 10%. From the above facts, it was found that the segregation of the constituent components of the target was sufficiently suppressed.

The Ti--Al sintered body thus prepared and A
The 1-backing plate and the backing plate were integrally joined by a solder joining method to obtain a Ti-Al sputtering target according to Example 3.

A Ti-Al sputtering target thus obtained was used to heat-oxidize the surface of a Si wafer, and the same magnetron sputtering apparatus as described above was used. The distance between the substrate and the target was 150 mm, and the back pressure was: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate:
TiA with a film thickness of 1000 Å under the conditions of 10 sccm, N ₂ gas flow rate: 20 sccm, and sputtering time: 10 min.
The 1N film was sputtered and the number of particles having a diameter of 0.2 μm or more mixed therein was investigated.

Further, thin film samples were taken from the 17 sites shown in FIG. 1 and the film thickness was measured using a film thickness measuring device, and the variation in the film thickness was determined by the above [(maximum value-minimum value)].
/ (Maximum value + minimum value) × 100 (%)], and the in-plane uniformity of the film thickness was evaluated. As a result, the number of particles having a diameter of 0.2 μm or more mixed in was 18 p / w and the variation in film thickness was 18%, and stable film formation operation could be realized.

Further, a W target was attached to the same sputtering apparatus, the substrate-target distance = 150 mm, back pressure: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar pressure:
Ti under the conditions of 0.5 Pa and sputter time: 5 min
A W film was formed on the AlN film at 1000 Å. Thereafter, the film-formed wafer is vacuumed at a temperature of 1 × 10 ⁻² Pa and a temperature of 6
After performing vacuum heat treatment at 00 ° C. for 3 hours, profile measurement was performed with an X-ray diffractometer of a scientific instrument to investigate whether or not an oxide of W was formed to evaluate the oxidation resistance of the thin film. . As a result, the peak intensity of W oxide was 20, and it was confirmed that sufficient oxidation resistance was obtained.

[0083]

Comparative Example 1 A target material for Comparative Example has a purity of 4N5.
Ti material and Al material having a purity of 4N are prepared, and Ti-30a
It was weighed so that the composition was t% Al. The Ti material and the Al material were set in a vacuum arc melting apparatus, the inside of the apparatus was evacuated to 5 × 10 ⁻³ Pa, and then an arc melting treatment was carried out to produce an ingot having a diameter of 80 mm and a length of 100 mm. The ingot obtained is machined to a diameter of 70 m
m × 100 mm in length, and using the obtained electrode material, melt dispersion treatment based on the plasma rotating electrode method (P-REP) was performed at a rotation speed of 6000 rpm, and Ti−
An Al alloy powder was produced. The average particle size of the alloy powder is 600
was μm. The alloy powder was filled in a carbon mold having a diameter of 130 mm, and the temperature rising rate in vacuum was 10 ° C.
/ Min heated to a temperature of 1250 ℃, pressure 24.5M
Sintering was performed for 4 hours using a pressure hot press machine under the condition of Pa.

The obtained sintered body was machined to a diameter of 127
After forming into a disc shape with a thickness of 5 mm and a thickness of 5 mm, an analysis is performed using an EPMA device (JEOL JXA-8600M), and Ti and A in a 200 μm square measurement region are measured.
An l-component color mapping was obtained. As a result, the number of Ti segregated portions having a minimum circle diameter of 2 μm or more surrounding a continuous portion having a measurement sensitivity count number of 3500 or more was 4, and the maximum diameter of the Ti segregated portion was 9 μm. .

Similarly, with respect to Al, the number of Al segregated portions having a minimum circle diameter of 2 μm or more surrounding a continuous portion having a measurement sensitivity count number of 400 or more is 6
The maximum diameter of the Al segregated portion was 12 μm.

Further, the measurement area was divided into four, and the area ratio of each segregated portion was measured for the Ti and Al components, and the variation thereof was calculated as [(maximum value-minimum value) /
(Maximum value + minimum value) × 100 (%)] is calculated by the equation (1). As a result, the variation in the area ratio of the Ti segregated portion was 19%, and the variation in the area ratio of the Al segregated portion was 1.
It was 0%. From the above facts, it was found that the segregation of the constituent components of the target was sufficiently suppressed.

The Ti--Al sintered body thus prepared and A
The 1-backing plate and the backing plate were integrally joined by a solder joining method to obtain a Ti-Al sputtering target according to Comparative Example 1.

TiAl sputter phosphorus thus obtained
The surface of the surface is treated with a thermal target using a target in the same manner as in Example 1.
Magnetron sputter phosphorus is formed on the converted Si wafer.
Board (ULVAC: SH-550)
Target distance = 150 mm, back pressure: 1 x 10^-5P
a, output: DC 2 kW, Ar flow rate: 10 sccm, N _Two
Gas flow rate: 20 sccm, sputtering time: 10 min
Under the conditions, sputtering of a TiAlN film with a thickness of 1000Å
Particles with a diameter of 0.2 μm or more
I investigated the number.

Further, thin film samples were taken from the 17 parts shown in FIG. 1 and the film thickness measuring device (Alpha-St) was used.
ep200), the film thickness is measured, and the variation in the film thickness is calculated as [(maximum value-minimum value) / (maximum value + minimum value) ×
100 (%)] was calculated by the equation (1), and the in-plane uniformity of the film thickness was evaluated. As a result, the number of particles with a diameter of 0.2 μm or more was 86 p / w, and the variation in film thickness was 40%. In the target of Comparative Example 1, the average particle size of the Ti—Al alloy powder after the melt dispersion treatment based on the plasma rotating electrode method (P-REP) is 60.
Since it was too large as 0 μm, the amount of particles generated was large and the variation in film thickness was large.

Further, a W target was set in the same sputtering apparatus, and the distance between the substrate and the target was 150 mm,
Under the conditions of back pressure: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate: 0.5 Pa, sputtering time: 5 min,
A W film was formed on the TiAlN film at 1000 Å. Thereafter, the film-formed wafer was vacuumed at 1 × 10 ⁻² Pa,
After carrying out vacuum heat treatment at a temperature of 600 ° C. for 3 hours, profile measurement was carried out by an X-ray diffractometer of a scientific instrument to investigate whether or not an oxide of W was formed to evaluate the oxidation resistance. . As a result, the peak intensity of the W oxide was 50, and it was confirmed that sufficient oxidation resistance was obtained.

[0091]

Comparative Example 2 A Ti material having a purity of 4N5 and an Al material having a purity of 4N were prepared and weighed so as to have a composition of Ti-15 at% Al. The Ti material and the Al material were set in a cold crucible melting apparatus, the apparatus was evacuated to a vacuum degree of 6 × 10 ⁻¹ Pa, and then a melting operation was performed.
An ingot having a diameter of 80 mm and a length of 100 mm was produced. The obtained ingot is machined to a diameter of 70 mm x
The electrode material having a length of 100 mm was used, and the obtained electrode material was subjected to P-REP treatment at a rotation speed of 8000 rpm to produce a Ti-Al alloy powder. The average particle size of the alloy powder was 350 μm. Diameter of the alloy powder 13
Fill a 0mm carbon mold, and in vacuum, 130
0 ° C. × 5 hr, heating rate: 10 ° C./min, pressure 24.
Sintering was performed using a pressure hot press machine under the condition of 5 MPa.

The obtained sintered body was machined to a diameter of 127
It was molded into a disk shape with a thickness of 5 mm and a thickness of 5 mm, and was analyzed using an EPMA apparatus in the same manner as in Example 1 to obtain color mapping of Ti and Al components within a 200 μm square measurement region. As a result, the number of Ti segregated portions having a minimum circle diameter of 2 μm or more surrounding a continuous portion having a measurement sensitivity count number of 3500 or more was 12, and the maximum diameter of the Ti segregated portion was 46 μm. .

Similarly, with respect to Al, the number of Al segregated portions having a minimum circle diameter of 2 μm or more surrounding a continuous portion having a measurement sensitivity count number of 400 or more is 4 or less.
The maximum diameter of the Al segregated portion was 40 μm.

Further, the measurement region was divided into four, and the area ratio of each segregated portion was measured for the Ti and Al components, and the variation thereof was calculated based on the equation (1). As a result, the variation in the area ratio of the Ti segregated portion is 20.
%, And the variation in the area ratio of the Al segregated portion was 48%. As a result, segregation occurred for both Ti and Al components.

A Ti-Al sputtering target according to Comparative Example 2 was obtained by integrally bonding the target sintered body and the Al backing plate using the solder bonding method.

A Ti-Al sputtering target thus obtained was used to heat-oxidize the surface of a Si wafer, and the same magnetron sputtering apparatus as described above was used. The distance between the substrate and the target was 150 mm, and the back pressure was: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate:
TiAl with a film thickness of 1000 Å under the conditions of 10 sccm, N ₂ flow rate: 20 sccm, and sputtering time: 10 min.
The N film was sputtered, and the number of particles mixed with a diameter of 0.2 μm or more was investigated.

Further, thin film samples were taken from the 17 parts shown in FIG. 1, the film thickness was measured using a film thickness measuring device, and the variation in the film thickness was calculated based on the equation (1). The in-plane uniformity of the film thickness was evaluated. As a result, the diameter of 0.
The number of particles having a particle size of 2 μm or more was 30 p / w, and the variation in film thickness was 35%, which is a result that cannot be said to be a stable film formation.

Further, a W target was attached to the same sputtering apparatus, the substrate-target distance = 150 mm, back pressure: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate:
Ti under the conditions of 0.5 Pa and sputter time: 5 min
A W film was formed on the AlN film at 1000 Å. Thereafter, the film-formed wafer is vacuumed at a temperature of 1 × 10 ⁻² Pa and a temperature of 6
The oxidation resistance of the thin film was evaluated by performing vacuum heat treatment at 00 ° C. for 3 hours, measuring the profile with an X-ray diffractometer of a scientific instrument, and investigating whether or not an oxide of W was formed. . As a result, the peak intensity of W oxide is 1
It was 000, and a small peak could be confirmed.
That is, it was found that the TiAlN film did not exhibit the barrier property and the oxygen component of the thermally oxidized Si was transmitted, and the function as the barrier metal layer was not exhibited.

[0099]

[Comparative Example 3] A Ti material having a purity of 4N5 and an Al material having a purity of 4N were prepared and weighed so as to have a composition composition of Ti-3 at% Al. After setting the Ti material and the Al material in the arc melting apparatus and exhausting the inside of the apparatus to 5 × 10 ⁻³ Pa,
Dissolution treatment was performed to produce an ingot having a diameter of 80 mm and a length of 100 mm. The obtained ingot was subjected to hot forging at a temperature of 1000 ° C until the processing rate reached 50%, and then hot cross rolling was performed at a temperature of 1000 ° C until the processing rate reached 80%, and further at a temperature of 900 ° C. A Ti—Al alloy plate was obtained by carrying out a recrystallization heat treatment for 1 hour. In this Comparative Example 3, the Al composition is 30%.
From the following, it was possible to perform plastic working that gives a high working ratio as described above.

The rolled material obtained was machined to a diameter of 127
mm-thick 5mm disk shape, EP as above
Analysis was performed using a MA device to obtain color mapping of Ti and Al components in a measurement area of 200 μm square.
As a result, the diameter T of the minimum circle surrounding the continuous portion where the count number of measurement sensitivity is 3500 or more is 2 μm or more.
The number of i-segregated portions present was 3, and the maximum diameter of the Ti-segregated portion was 70 μm or more.

Similarly, regarding Al, the number of existing Al segregated portions having a diameter of a minimum circle of 2 μm or more surrounding a continuous portion with a count number of measurement sensitivity of 400 or more is 1
The maximum diameter of the Al segregated portion was 5 μm.

Further, the above-mentioned measurement region was divided into four, the area ratios of the segregated portions of the Ti and Al components were measured, and the variation thereof was calculated by the above equation (1). As a result, the variation in the area ratio of the Ti segregated portion was 59%,
The variation in the area ratio of the Al segregated portion was 14%. This is because the target of Comparative Example 3 has a composition in which Ti is much larger than the amount of Al.
₃ Al formation occurs only in a small range, and Ti
This is because the component exists alone.

A Ti-Al sputtering target according to Comparative Example 3 was obtained by integrally bonding the sintered body for a target and the Al backing plate using the solder bonding method.

A Ti-Al sputtering target thus obtained was used to heat-oxidize the surface of the Si wafer, and the same magnetron sputtering apparatus as described above was used. The distance between the substrate and the target was 150 mm, and the back pressure was:
1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate: 10
sccm, N ₂ flow rate: 20 sccm, sputtering time: 1
A TiAlN film having a film thickness of 1000 Å was sputtered under the condition of 0 min, and the number of particles mixed with a diameter of 0.2 μm or more was investigated.

Further, thin film samples were taken from the 17 parts shown in FIG. 1, the film thickness was measured using a film thickness measuring device, and the variation in the film thickness was calculated by the above equation (1). The in-plane uniformity of thickness was evaluated. As a result, the number of particles having a diameter of 0.2 μm or more mixed in was 40 p / w, the variation in film thickness was 55%, and it was difficult to say that the film was stably formed.

Furthermore, a W target was set in the same sputtering apparatus, and the distance between the substrate and the target was 150 mm,
Under the conditions of back pressure: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate: 0.5 Pa, sputtering time: 5 min,
A W film was formed on the TiAlN film at 1000 Å. Thereafter, the film-formed wafer was vacuumed at 1 × 10 ⁻² Pa,
Evaluate the oxidation resistance of the thin film by performing vacuum heat treatment at a temperature of 600 ° C for 3 hours, measuring the profile with an X-ray diffractometer of scientific equipment, and investigating whether or not an oxide of W is formed. did. As a result, the peak intensity of the W oxide was 2100, and a large diffraction peak could be confirmed. That is, in Comparative Example 3, since the Ti component was excessive, the TiAlN film did not exhibit the barrier property and the oxygen component of the thermally oxidized Si was allowed to permeate, and the function as the barrier metal layer was not exhibited. .

[0107]

Comparative Example 4 A Ti powder having a purity of 4N5 and an Al powder having a purity of 4N were prepared and weighed so as to have a blended composition of Ti-70 at% Al. The Ti powder and the Al powder were mixed in a ball mill for 24 hours, and the mixed powder had a diameter of 130 mm.
Fill the carbon mold of 1300 ℃ in vacuum
5 hours, heating rate: 10 ° C / min, pressure 29.4MP
Under the conditions of a, it sintered using the pressure hot press apparatus.

The resulting sintered body was machined to a diameter of 127
mm-thick 5mm disk shape, EP as above
Analysis was performed using a MA device to obtain color mapping of Ti and Al components in a measurement area of 200 μm square.
As a result, the diameter T of the minimum circle surrounding the continuous portion where the count number of measurement sensitivity is 3500 or more is 2 μm or more.
The number of i segregated portions was 17, and the maximum diameter of the Ti segregated portion was 8 μm or more.

Similarly, with respect to Al, the number of Al segregated portions having a minimum circle diameter of 2 μm or more surrounding a continuous portion having a measurement sensitivity count number of 400 or more is 2 or less.
It was 0, and the maximum diameter of the Al segregated portion was 15 μm.

Further, the above-mentioned measurement region was divided into four, the area ratios of the segregated portions of Ti and Al components were measured, and the variation thereof was calculated by the above equation (1). As a result, the variation in the area ratio of the Ti segregated portion was 15%,
The variation in the area ratio of the Al segregated portion was 15%. Therefore, it can be said that the target of Comparative Example 3 can suppress the segregation of Ti and Al.

A Ti-Al sputtering target according to Comparative Example 4 was obtained by integrally bonding the sintered body for a target and the Al backing plate using the solder bonding method.

A Ti-Al sputtering target thus obtained was used to heat-oxidize the surface of a Si wafer, and the same magnetron sputtering apparatus as described above was used. The distance between the substrate and the target was 150 mm, and the back pressure was: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate:
TiAl with a film thickness of 1000 Å under the conditions of 10 sccm, N ₂ flow rate: 20 sccm, and sputtering time: 10 min.
The N film was sputtered, and the number of particles mixed with a diameter of 0.2 μm or more was investigated.

Further, thin film samples were taken from the 17 parts shown in FIG. 1, the film thickness was measured using a film thickness measuring device, and the variation in the film thickness was calculated by the above formula (1). The in-plane uniformity of thickness was evaluated. As a result, the number of particles having a diameter of 0.2 μm or more mixed in was 120 p / w, and the variation in film thickness was 16%, which is difficult to say that the film is stably formed.

Further, a W target was attached to the same sputtering apparatus, the substrate-target distance = 150 mm, back pressure: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate:
Ti under the conditions of 0.5 Pa and sputter time: 5 min
A W film was formed on the AlN film at 1000 Å. Thereafter, the film-formed wafer is vacuumed at a temperature of 1 × 10 ⁻² Pa and a temperature of 6
The oxidation resistance of the thin film was evaluated by performing vacuum heat treatment at 00 ° C. for 3 hours, measuring the profile with an X-ray diffractometer of a scientific instrument, and examining whether or not an oxide of W was formed. As a result, the peak intensity of W oxide is 25
00, and a large diffraction peak was confirmed. this is,
Since the target according to Comparative Example 4 is formed by the powder sintering method, it has a large amount of residual gas components and further has a further Al content.
Since the composition is too large, the TiAlN film does not exhibit the barrier property, resulting in the permeation of the oxygen component of the thermally oxidized Si.

[0115]

[Comparative Example 5] A Ti material having a purity of 4N5 and an Al material having a purity of 4N were prepared and weighed so as to have a compounding composition of Ti-45 at% Al. The Ti material and the Al material were set in a cold crucible melting apparatus, and the inside of the apparatus was evacuated to 7 × 10 ⁻³ Pa, followed by melting treatment to produce an ingot having a diameter of 130 mm × a length of 100 mm.

The resulting melt was machined to a diameter of 127
mm-thick 5mm disk shape, EP as above
Analysis was performed using a MA device to obtain color mapping of Ti and Al components in a measurement area of 200 μm square.
As a result, the diameter T of the minimum circle surrounding the continuous portion where the count number of measurement sensitivity is 3500 or more is 2 μm or more.
The number of i segregated portions was 8, and the maximum diameter of the Ti segregated portion was 38 μm or more.

Similarly, with respect to Al, the number of Al segregated portions in which the diameter of the smallest circle surrounding a continuous portion whose count number of measurement sensitivity is 400 or more is 2 μm or more is 1 is 1.
The number was 0, and the maximum diameter of the Al segregated portion was 30 μm.

Further, the above-mentioned measurement region was divided into four, the area ratios of the segregated portions of Ti and Al components were measured, and the variation thereof was calculated by the above formula (1). As a result, the variation in the area ratio of the Ti segregated portion was 25%, and the variation in the area ratio of the Al segregated portion was 50%. From the above facts, it was found that segregation often occurs especially for the Al component.

A Ti—Al sputtering target according to Comparative Example 5 was obtained by integrally bonding the target sintered body and the Al backing plate by using the solder bonding method.

Using the Ti—Al sputtering target thus obtained, the surface of the Si wafer was thermally oxidized, using the same magnetron sputtering device as described above, the substrate-target distance = 150 mm, the back pressure: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate:
TiAl with a film thickness of 1000 Å under the conditions of 10 sccm, N ₂ flow rate: 20 sccm, and sputtering time: 10 min.
The N film was sputtered, and the number of particles mixed with a diameter of 0.2 μm or more was investigated.

Further, thin film samples were taken from the 17 parts shown in FIG. 1, the film thickness was measured using a film thickness measuring device, and the variation in the film thickness was calculated by the above formula (1). The in-plane uniformity of thickness was evaluated. As a result, the number of particles with a diameter of 0.2 μm or more mixed in was 58 p / w, the variation in film thickness was 36%, and the amount of particles generated was particularly large, and it is difficult to say that stable film formation is possible. Became. This is considered to be due to the coarsening of the crystal grain size because the method of manufacturing the target according to Comparative Example 5 was ingot slice.

Further, a W target was attached to the same sputtering apparatus, the substrate-target distance = 150 mm, back pressure: 1 × 10 ⁻⁵ Pa, output: DC 2 kW, Ar flow rate:
Ti under the conditions of 0.5 Pa and sputter time: 5 min
A W film was formed on the AlN film at 1000 Å. Thereafter, the film-formed wafer is vacuumed at a temperature of 1 × 10 ⁻² Pa and a temperature of 6
After performing vacuum heat treatment at 00 ° C for 3 hours, profile measurement is performed with an X-ray diffractometer of a scientific instrument to investigate whether or not an oxide of W is formed to evaluate the oxidation resistance of the thin film. did. As a result, the peak intensity of the W oxide was 900, and a small peak was confirmed. That is, it means that the TiAlN film does not exhibit the barrier property and allows the oxygen component of the thermally oxidized Si to pass therethrough, which results in that the function as the barrier metal layer is not exhibited.

Table 1 below shows the composition, manufacturing method, target structure and characteristics of the thin film formed by sputtering the target according to each of the above Examples and Comparative Examples.

[0124]

[Table 1]

As is clear from the results shown in Table 1,
Compared with the targets of each comparative example, the amount of segregation and its variation in the target structure according to each example are much smaller, and the uniformity is excellent. Further, comparing the variations in the film thickness formed using each target and the number of particles mixed in, it is clear that the sputtering target according to the present embodiment can realize more stable sputtering characteristics than before. did. Therefore, the manufacturing yield of semiconductor products using thin films can be significantly improved, which is extremely effective in forming high quality thin films for electrodes and wiring materials of semiconductor devices.

[0126]

As described above, according to the sputtering target and the method for manufacturing the same according to the present invention, the mother alloy prepared by the vacuum melting method is made into the alloy powder having a predetermined particle diameter by the rotating electrode method and is sintered. Since the target is formed in this way, the segregation is small, the constituent components are uniformly dispersed, and the target in which the generation of particles and abnormal discharge is small can be obtained. Moreover, when sputtering is performed using this target, a wiring film or the like having excellent in-plane uniformity such as oxidation resistance, adhesion, and film thickness can be efficiently formed.

[Brief description of drawings]

FIG. 1 is a plan view showing a position where a sample is taken from a thin film formed by sputtering using a sputtering target according to the present invention.

[Explanation of symbols]

1 to 17 Thin film sample collection position

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 21/285 H01L 21/285 S (72) Inventor Koichi Watanabe 8 Shinsugita-cho, Isogo-ku, Yokohama, Kanagawa Formula company Toshiba Yokohama office (72) Inventor Yukinobu Suzuki 8 Shinsita-cho, Isogo-ku, Yokohama-shi Kanagawa Stock company Toshiba Yokohama office (72) Inventor Naomi Fujioka 8 Shinsugita-cho, Isogo-ku Yokohama-shi Kanagawa Stock company F term in Toshiba Yokohama office (reference) 4K017 AA04 BA10 BB01 CA07 DA09 EF07 4K018 AA06 AA14 BA03 BA08 BC02 BC09 BD10 EA02 EA13 EA22 KA29 4K029 BA23 BC01 BD02 DC04 DC08 DC09 4M104 BB36 DD40 DD42

Claims (9)

[Claims] 1. Containing 5 to 60 atomic% of aluminum,
When Al mapping is performed by EPMA analysis in a sputtering target whose remaining component is substantially titanium, a minimum circle surrounding a continuous portion having a measurement sensitivity count number of 400 or more in a measurement area of 200 μm square A sputtering target, wherein the number of Al segregated portions having a diameter of 2 μm or more is 5 or less in the measurement region. 2. The sputtering target according to claim 1, wherein when the titanium is mapped by the EPMA analysis, a minimum number surrounding a continuous region where a measurement sensitivity count number is 3500 or more within a measurement area of 200 μm square. A sputtering target, wherein the number of existing Ti segregation portions having a circle diameter of 2 μm or more is 5 or less in the measurement region. 3. The sputtering target according to claim 1, wherein, when Al mapping is performed by the EPMA analysis, a measurement sensitivity count number is obtained in each of divided areas obtained by dividing a 200 μm square measurement area into four equal areas. When the area ratio of the Al segregated portion having a value of 400 or more is measured, the variation of the area ratio in each divided region is 30%.
Sputtering target characterized by being within. 4. The sputtering target according to claim 2, wherein when the Ti is mapped by the EPMA analysis, the measurement sensitivity is counted in each of divided areas obtained by dividing a measurement area of 200 μm square into four equal areas. When the area ratio of the Ti segregated portion having a value of 4700 or more is measured, the variation of the area ratio in each divided region is 30.
% Sputtering target. 5. The sputtering target according to claim 1, wherein the maximum diameter of the Al segregated portion is 30 μm or less. 6. The sputtering target according to claim 2, wherein the Ti segregation portion has a maximum diameter of 30 μm or less. 7. Containing 5 to 60 atomic% of aluminum,
The minimum circle that surrounds a continuous portion where the count number of the measurement sensitivity is 400 or more within a measurement area of 200 μm square when Al mapping is performed by EPMA analysis when the remaining component is a sputtering target that is substantially composed of titanium. In a method of manufacturing a sputtering target having 5 or less Al segregated portions having a diameter of 2 μm or more in the measurement region, an aluminum material and a titanium material are blended so that the aluminum content is 5 to 60 atom%. And a step of preparing a raw material body by melting the raw material body by a vacuum melting method to solidify the raw material body.
a step of preparing an i-Al master alloy, and a step of preparing a Ti-Al alloy powder containing aluminum in an amount of 5 to 60 at% and having a particle diameter of 500 μm or less by melting and dispersing the prepared Ti-Al master alloy by a rotating electrode method. Then, the obtained Ti-Al alloy powder is compacted and sintered to obtain Ti-Al.
A method of manufacturing a sputtering target, comprising the steps of producing an alloy sintered body and using it as a sputtering target. 8. The method for manufacturing a sputtering target according to claim 7, wherein the vacuum melting method is any one of a vacuum arc melting method, a cold crucible melting method, and an electron beam melting method. . 9. The method for manufacturing a sputtering target according to claim 8, wherein the sintering is performed based on any one of a hot press sintering method, a hot isostatic pressing method and a plasma discharge sintering method. And a method for manufacturing a sputtering target.