TWI246874B - Hillock-free aluminum metal layer and method of forming the same - Google Patents

Abstract

A hillock-free aluminum metal layer and method of forming the same are provided. A barrier aluminum layer is first formed on the substrate, and then an aluminum layer is formed over the barrier aluminum layer. The thermal expansion coefficient (CTE) of the barrier aluminum layer is between the CTE of the substrate and the CTE of the aluminum layer (i.e. CTE sub. < CTE b. Al < CTE Al), so as to be a barrier layer for inhibiting the occurrence of hillocks. The electrical product manufactured according to the invention has a great reliability, and the manufacturing cost thereof is also decreased.

Description

1246874 发明Invention Description: TECHNICAL FIELD The present invention relates to an aluminum metal layer, and more particularly to a Hillock-Free Aluminum Layer and a method of manufacturing the same. [Prior Art] In the semiconductor process, metals such as molybdenum (M〇), tantalum (Tatalum'Ta), chromium (Chromium'Cr), and cast (Tungsten, W) are generally used.

Alloys are used as the metal layer. However, expensive metals such as molybdenum or chromium can keep the cost of the entire process high. The most abundant metal ore on the earth, aluminum, is not only easy to obtain, but also inexpensive. It is generally used in metal processes. However, if aluminum is used in the metal process, there will be a small convex surface after the subsequent high temperature process. The problem of lifting or styling (Hillock). The advantage of using aluminum is that aluminum has a low electrical resistivity and good adhesion to the substrate, and it also exhibits better Etching Characteristics in the process. However, the use of aluminum having a lower melting point (Melting Point) than ordinary metals as a metal has its drawbacks. Please refer to FIG. 1A, which shows a schematic diagram of metal deposition on a glass substrate. The metal is first deposited on the glass substrate 1〇2 at a lower temperature (about 150 ° C), so that the glass substrate 102 has grains (104), and there is crystal between the grains 104 and the grains 104. The Grain Boundary 106 is formed. Of course, the actual crystal grains are not as square as in Fig. 1A, and are shown here as neat square grains for convenience of explanation. Then, the metal layer is annealed. As the temperature increases, both the metal layer and the substrate expand due to heat, but the thermal expansion coefficients are not the same between the two, which makes There is considerable mismatch between the metal layer and the substrate. The difference between the thermal expansion coefficient of the metal layer and the substrate by 1246874 will cause a compressive stress on the metal layer at the interface between the two, while the metal The layer releases the stress to produce a small surface protrusion or a bulge to eliminate the inconsistency between the metal layer and the substrate interface. When using the metal layer as a metal layer, there is a problem of small bumps. Please refer to FIG. 1B for a schematic view of the annealed aluminum on the glass substrate. The high temperature of the annealing process causes the thermal expansion of the crystal grain 104 and the glass substrate 1〇2 (Therma丨Expansion) 'Because the aluminum system adheres to the glass substrate 1〇2, the thermal expansion coefficient of aluminum is greater than the thermal expansion coefficient of the glass, so that aluminum The grain 1 〇4 is subjected to a very large compressive stress Φ (ComPressive Stress). In order to relieve the compressive stress, the aluminum atoms diffuse along the grain boundary 106, thereby accumulating and growing, and forming a small protrusion or an aluminum tip convex thereon ( Hillock) 11〇. This small bump or aluminum tip 11 () formed on the metal layer will cause the surface of the component to be rough and cause leakage, short circuit or influence of field effect (Fje丨d Effec, etc. :! There are two kinds of #见Traditionally, to solve the problem of small bumps or pointed bumps, the method is as follows: The first traditional solution is to add a little more melting point to other elements such as niobium (Nd) and titanium (Ti).鍅 (Zr), button (Ta), tantalum, or copper (Cu). Since non-aluminum elements are not miscible with aluminum, Φ non-aluminine will transfer to grain boundaries while grain growth, but in grain boundaries Gathering into a small particle, these small particles will block the channel of the grain boundary, so that when growing along the grain boundary, it cannot protrude above the grain by small particles, thereby suppressing the formation of small protrusions. Among them, Kobelco The proposed aluminum-bismuth (A1-Nd) alloy is the most well-known and widely used. However, Nd is a rare metal, which is expensive, and because of doping, it is necessary to use a sputtering rate (Sputtering Rate). Prevent the generation of Splash, and more importantly, titanium has high power The value of aluminum bismuth alloy is much higher than that of aluminum, which is the same as above. The method will increase the cost and increase the resistance value. The second method is to coat the aluminum with a layer of high melting point metal. Prevents the growth of the 1246874 J bump. This is done above the aluminum grain of the glass substrate, first plated with a melting point, and then annealed to the metal layer. Since the metal layer covers the grain boundary like a lid π, because the ruthenium can be formed on the top of the grain boundary, the metal layer used for the system is chromium (Chromium, Cr), 目 (lybdenum 'M〇), ! giant (Tantalum, Ta), 鹞 (Tungsten , W), etc. Although maintaining the low resistivity of aluminum, good adhesion to the substrate, and exhibiting better etching characteristics during the etching process, another non-aluminum metal layer process must be provided. The invention provides an additional method. Only one aluminum metal layer is used, which makes it costly to manufacture. The above two methods are inexpensive, and can suppress small bumps, and provide a metal layer without a small bump (HHI). 〇Ck_Free Aluminum Layer ) and The manufacturing method has the advantages of low resistivity of aluminum itself, good adhesion to the substrate, and good etching characteristics in the etching process. According to the above, how is the general semiconductor process or In the aluminum metal system of liquid crystal display, it is an important research goal in the industry to reduce the cost, but it can prevent the occurrence of small bumps or Hi Mocks. The object of the present invention is to provide an aluminum metal layer without small protrusions and a manufacturing method thereof, and the small number of swells and swells between the substrate and the shape are small uneven protrusions or Hi 丨丨〇 Ck). Not only does the component have good electrical conductivity properties, but the manufacturing cost is greatly reduced. According to the purpose of the present invention, a metal layer having no small bumps is provided, and at least two layers of the layer are formed on the substrate, and the metal layer includes a buffer aluminum 1246874. The buffer aluminum layer may be composed of aluminum nitride (Aluminum Nitride, AINx), aluminum oxide (Aluminum Oxide) or aluminum oxide (Aluminum Oxide-Nitride, AlOxNy), or a plurality of layers of the above. The composite metal layer or the like, and the thermal expansion coefficient of the buffer aluminum layer is smaller than the thermal expansion coefficient of the aluminum layer and larger than the thermal expansion coefficient of the substrate. Wherein, the thickness of the layer is between 1 and 4500 A, and the thickness ratio of the buffered aluminum layer to the aluminum layer is between about 1:6 and 1:1. In addition, in order to obtain a low resistivity (Resistivity) and a good cross-section (pr〇fj|e) of the component after the subsequent process, the thickness of the buffer I ly layer is preferably smaller than the thickness of the lyon layer. Wherein, the thickness of the aluminum layer is between 1 〇〇〇A and 45 〇〇A' and the thickness ratio of the buffered aluminum layer to the aluminum layer ranges from about 1:6 to about 2:2. The above described objects, features, and advantages of the present invention will become more apparent from the aspects of the embodiments of the invention. A buffer aluminum layer is first formed on the substrate, and then an aluminum layer is formed over the buffer aluminum layer. The thermal expansion coefficient of the buffer aluminum layer is smaller than the thermal expansion coefficient of the underlayer and larger than the thermal expansion coefficient of the substrate to suppress the generation of small bumps. Illustrated in Figure 2, a schematic view of an aluminum layer capable of suppressing small bumps in accordance with a preferred embodiment of the present invention is shown. Taking the glass substrate 202 as an example, a buffer aluminum layer 204 is formed on the upper surface, for example, aluminum nitride (Aluminum Nitride, AINx), oxidized aluminum (Alum_mum Oxide) or nitrogen-containing aluminum oxide (A|um丨num Oxide- Nitride, AlOxNy), or a multi-layer composite metal layer or the like in which the above three are matched with each other, and then a layer of |g is formed over the buffer layer 204. 1246874 wherein the buffer aluminum layer 204 sandwiched between the glass substrate 202 and the aluminum layer 206 has a coefficient of thermal expansion therebetween, and therefore, the formation of small bumps can be suppressed in a subsequent high-temperature process. Table 1 shows the thermal expansion coefficient and resistivity (Resistivity) of different glass substrates provided by aluminum, aluminum nitride, aluminum oxide, nitrogen-containing aluminum oxide and three manufacturers before annealing. Table I

Corning (glass substrate) NHT (glass substrate) Asahi (glass substrate) Aluminum (ΑΙ) Aluminum nitride (ΑΙΝ) Alumina (Al2〇3) Nitrogen-containing alumina (AlOxNy) Model 1737 E2000 NA35 NA25 NA30 AN 100 Thermal expansion Coefficient (x10_7/°C) 37.8 32 37 26 32 38 231 45 81 45 ~81 Resistivity (.cm) NA NA NA NA NA ΝΑ 2.65x106 5.6x1013 2χ1013 2x1013 ~5.6x1013

When the annealing is performed, the difference in thermal expansion coefficient between the glass substrate 202 and the aluminum layer 206 is too large, so that small bumps are formed on the surface of the aluminum layer 206. If a buffer aluminum layer 204 is applied between the glass substrate 202 and the aluminum layer 206, the buffer aluminum is used. The coefficient of thermal expansion of the layer 204 is between the glass substrate 202 and the aluminum layer 206, and the configuration can slow the stress between the glass substrate 202 and the aluminum layer 206, so that the buffer aluminum layer 2〇4 closest to the glass substrate has a similar buffer (already The action of 1^0|1|19), therefore, after annealing, the formation of small bumps on the surface of the aluminum layer 206 can be suppressed. At the same time, in order to obtain a low resistivity and a subsequent process such as an etched component having a good profile, the thickness of the buffered aluminum layer 204 is preferably less than the thickness of the layer 206. In the following, a series of experiments were carried out on the aluminum metal layer structure of the present invention, and argon (Ar) sputtering was applied to a vacuum chamber of an aluminum target 1246874 (Vacuum Cham be r).

An aluminum layer can be obtained. As for the buffer aluminum layer, an aluminum nitride layer (AINx) can be obtained by sputtering with argon gas and nitrogen gas (N2), and argon gas and oxygen gas (02) can be used for sputtering to obtain oxidation. In the layer (Al Ox), a nitrogen-containing aluminum oxide layer (AlOxNy) is obtained by passing argon, nitrogen and oxygen into the money clock, and the annealing temperature is 340 ° C and the annealing time (Annealing Time) is 30 minutes. After that, a scanning electron microscope (Scanning Electron Microscope) was used to observe whether there was a small protrusion above the inscription layer and its profile. Some of the experimental results of the present invention are shown in Table 2. Table 2 Experimental buffer in Lu film thickness (Λ) Aluminum film thickness (Λ) Buffer aluminum layer and aluminum layer film thickness ratio after annealing to produce a small convex section structure (Profile) A 0 2000 0 Yes - One - 200 2000 1:10 is not good three 300 2000 1 : 6_7 is not good four 400 2000 1:5 no good five 500 2000 1:4 no good six 600 2000 1 : 3.3 no good seven 1000 2000 1:2 no good eight 1500 2000 1:1.3 Nothing good nine 2000 2000 1:1 No bad ten 250 1800 1:7.2 is not good Η — 300 1800 1:6 No good twelve 900 1800 1:2 No good thirteen 1800 1800 1: 1 Nothing good 10 1246874 Fourteen 300 2500 1 : 8.3 is not good fifteen 400 2500 1 : 6_3 No good sixteen 600 2500 1:4.2 No good seventeen 700 2500 1:3.6 No good eighteen 1250 2500 1:2 No good nineteen 2500 2500 1:1 no bad twenty 600 4500 1 :7_5 is not good twenty one 750 4500 1:6 no good twenty two 1500 4500 1:3 no good twenty three 2250 4500 1:2 No good twenty four 4500 4500 1:1 no bad

Experiment 1 (control group) A single layer of aluminum was sputtered onto a glass substrate at a film formation pressure of 0.3 Pa, and the film thickness was about 2000 Å. After annealing at 340 ° C for 30 minutes, a scanning electron microscope (SEM) was used to observe the presence of small protrusions on the aluminum layer. The observation shows that the aluminum layer produces small bumps after annealing without any other intermediates being buffered. In the second experiment, a buffered layer was deposited on the glass substrate at a film formation pressure of 0.5 P a. The experiment was performed on the aluminum nitride layer (AINx), the aluminum oxide layer (ΑΙΟχ) and the nitrogen-containing aluminum oxide layer (AlOxNy). The film thickness is about 20 〇Λ. Next, an aluminum layer was deposited over the buffer aluminum layer at a film formation pressure of 0.3 Pa, and the film thickness was about 2000 Å. That is, at this time, the film thickness ratio of the buffer aluminum layer to the aluminum layer is 1:10, and a 200 Å aluminum nitride layer (AINx) 11 1246874 is deposited on the aluminum layer of 2000 A, and the aluminum oxide layer (ΑΙΟχ) is deposited on the aluminum oxide layer (ΑΙΟχ). A 2000-into-aluminum layer and a 200-inch aluminum-containing aluminum oxide layer (AlOxNy) were deposited with a 2000-in-aluminum layer, which was annealed at 340 ° C for 30 minutes and then scanned by electron microscopy (SEM). ) Observe whether there is a small protrusion above the aluminum layer and its profile. The observation results show that a 2000-aluminum layer is deposited on the above-mentioned 200 Å aluminum nitride layer (AINx), a 2000 A aluminum layer is deposited on the 200 A aluminum oxide layer (ΑΙΟχ), and a nitrogen-containing aluminum oxide layer is deposited on the 200 Å aluminum oxide layer (AlOxNy). ) depositing a layer of 2000 into the aluminum layer, at 200

In the case where the buffer aluminum layer is buffered, the film thickness ratio of the buffer aluminum layer to the aluminum layer is 1:1 0, and the aluminum layer is observed to have small bumps and cross-sectional structures after annealing, and the film thickness ratio is not completely complete. The stress of the substrate and the aluminum layer is alleviated and the profile of the profile is poor. Experiment 3 As in the method of Experiment 2, a buffered aluminum layer was deposited on the glass substrate, and the film thickness was about 300 Å. Next, a layer of a layer is deposited over the buffer layer, and the film thickness is about 2000 Å. At this time, the film thickness ratio of the buffer aluminum layer to the aluminum layer is 1:6. After annealing at 340 ° C and tempering time for 30 minutes, the aluminum layer was observed by scanning electron microscopy (SEM). The aluminum layer was observed to have small protrusions and cross-sectional structure after annealing. The film thickness ratio is not complete. The stress of the substrate and the aluminum layer is alleviated and the profile of the profile is poor, resulting in over-etching of the buffered aluminum layer. Experiment 4 As in the second and third methods, in the fourth experiment, a buffer layer of about 400 A was deposited on the glass substrate. Next, a 12 1246874 aluminum layer having a film thickness of about 2000 A is deposited over the buffer layer, and the film thickness ratio of the buffer aluminum layer to the aluminum layer is 1:5. The observation results show that a 2,000 A aluminum layer and a 400 A aluminum oxide layer (ΑΙΟχ) are deposited on the above 400 A aluminum nitride layer (AINx), and a 2000 A layer is deposited on the Lu layer and 400 into the nitrogen oxide layer. On the AlOxNy), a layer of 2000 A is deposited. In the case where the buffer layer of the 40 〇A buffer is used, the film thickness ratio of the buffer layer to the chain layer is 1:5, and the underlayer is observed to be slightly convex after annealing. Since it can be completely suppressed and cannot be produced, it can be seen that the film thickness ratio of 1:5 can effectively suppress the stress of the substrate and the aluminum layer and a good cross-sectional structure can be obtained. On the glass substrate, a buffer layer of about 5 〇〇A is deposited first, and the thickness of the deposited layer is about 2000 A. The film thickness ratio of the buffer layer to the layer is 1:4, and the aluminum layer is annealed. Small bumps can be completely suppressed and cannot be produced. The composite house first deposits a buffer layer of about 6 膜 on the glass substrate, and then deposits an aluminum layer with a film thickness of about 2000 Å. The film thickness ratio of the buffer aluminum layer to the aluminum layer is 1:3_3, aluminum. After the layer is annealed, the small protrusions can be completely suppressed and cannot be produced and a good cross-sectional structure can be obtained. On the glass substrate, a buffer layer of about 10 Å is deposited on the glass substrate, and an aluminum layer with a film thickness of about 2000 Å is deposited. The film thickness ratio of the buffer aluminum layer to the aluminum layer is 1:2, and the aluminum layer is After annealing, the small protrusions are completely suppressed and cannot be produced and a good cross-sectional structure can be obtained. A buffer aluminum layer with a film thickness of about 15 Å is deposited on the glass substrate, and an aluminum layer with a film thickness of about 2000 Å is deposited. The film thickness ratio of the buffer aluminum layer to the aluminum layer is 1:1.3 Å. After the annealing, the small protrusions can be completely suppressed and cannot be produced, but the 13 1246874 ^ d surface, and the alpha structure cause the over-etching of the aluminum layer, so that the buffer aluminum layer is insufficiently etched to leave an excessively long buffer layer. - depositing a buffered aluminum having a film thickness of about 2 Å on the glass substrate: a film thickness ratio of the aluminum layer buffered aluminum layer to the aluminum layer of about 2,000 Å and a film thickness of about 2,000 Å, the layer is After annealing, the small bumps can be completely suppressed and cannot be produced, but the cross-section of the structure causes the layer to pass (4), so that the buffer (4) (four) is insufficient to leave too long buffer! Lu layer. Similarly, in Experiments 4 to 9, annealing was also carried out at a temperature of 30 minutes, and the upper portion of the aluminum layer was observed by a scanning electron microscope (Sem), and it was found that the small protrusions were completely suppressed and could not be produced. &lt; Fish soil and the above experiment 2 on the glass substrate first deposited a film thickness of about 25 〇 buffer _, and then immersed in the thickness of about 4 1 _ 铭 铭 layer, the towel, buffer layer and aluminum layer film thickness ratio is 1: 7_2, also annealed at a temperature of 340 ° C for 30 minutes, and then observed above the aluminum layer by scanning electron microscopy (SEM). After annealing, S produced small protrusions, which could not completely alleviate the substrate and aluminum. The stress of the layer and its poor profile result in over-etching of the buffered aluminum layer. ΐ·土土二__1 Firstly, a buffered aluminum layer with a film thickness of about 3 Å is deposited on the glass substrate, and a film thickness of about 1800 Å is deposited on the glass substrate, wherein the film thickness ratio of the buffer aluminum layer to the aluminum layer is It was 1:6, and it was annealed at a temperature of 34 ° C for 3 minutes. The upper layer of the aluminum layer was observed by a scanning electron microscope (SEM). It was found that the small protrusions were completely suppressed and could not be produced, and Good cross-sectional structure. . A buffer layer having a film thickness of about 90 〇a is deposited on the glass substrate, and an aluminum layer having a film thickness of about 1800 Å is deposited, wherein the film thickness ratio of the buffer aluminum layer to the aluminum layer 14 1246874 is 1:2. The temperature is 34 〇. After annealing for 3 minutes, the top layer of the inscription was observed by a scanning electron microscope (SEM), and it was found that the small protrusions were completely suppressed and could not be produced, and a good cross-sectional structure was obtained. The fork first deposits a buffer aluminum layer with a thickness of about 18 在 on the glass substrate, and then deposits a layer with a thickness of about (10) Ο A, wherein the thickness of the buffer layer is 1:1, and the thickness ratio is 1:1. Take the temperature 34. . Oh, time 3. Annealing was performed in minutes, and the upper layer of the aluminum layer was observed by scanning electron microscopy (SEM). It was found that the small protrusions could be completely φ: the skin was suppressed and could not be produced, but the cross-sectional structure caused the etching of the buffered aluminum layer due to the over-synchronization of the layer. Leave a long buffered aluminum layer. A buffer aluminum layer having a film thickness of about 3 Å is deposited on the glass substrate, and an aluminum layer having a film thickness of about 2500 Å is deposited, wherein the film thickness ratio of the buffer aluminum layer to the aluminum layer is 1:8.3, Annealing at a temperature of 34 rc for 3 minutes, and observing the upper layer of the aluminum layer by a scanning electron microscope (SEM), a small protrusion is formed after annealing, and the film thickness ratio cannot completely alleviate the stress of the substrate and the aluminum layer. And the profile of the profile is poor, causing the buffer aluminum layer to be over-etched. On the glass substrate, a buffer layer of about 4 Å is deposited first, and then an aluminum layer having a film thickness of about 2500 Å is deposited. The film thickness ratio of the buffer aluminum layer to the aluminum layer is 1:6_3, and the temperature is also 340. The annealing time is 30 minutes, and the upper layer of the aluminum layer is observed by a scanning electron microscope (SEM), and it is found that the small protrusion can be completely suppressed. It can not be produced, and a good cross-sectional structure can be obtained. A buffer aluminum layer with a film thickness of about 600 people is deposited on the glass substrate, and an aluminum layer with a film thickness of about 2500 Å is deposited, wherein the buffer aluminum layer and the aluminum layer 15 1246874 The film thickness ratio is 1:4·2, and it is also at a temperature of 34 〇χ and time 3 〇 minutes. Annealing, ^ observation of the upper layer of the aluminum layer by electron microscopy (SEM), found that the small protrusion can be completely suppressed and can not be produced, and a good cross-sectional structure can be obtained. On the glass substrate, the film thickness is about 7〇〇.缓冲 缓冲 buffer aluminum ★ redeposited film thickness of about 2500 铝 aluminum layer, wherein the ratio of buffer aluminum layer to aluminum film 2: 1:3.6, also temperature 34 (rC, time 3 〇 minutes annealing, then Scanning his electron microscope (SEM) to observe the upper layer of the aluminum layer, it is found that the small protrusion can be suppressed and can not be produced, and a good cross-sectional structure can be obtained. The soil is first deposited on the glass substrate by about 125 〇. The buffered aluminum layer is re-deposited with a thickness of about 2500 A. The film thickness ratio of the buffer layer to the inscription layer is 1:2, and the temperature is 34 (rc, time % minute annealing, and then scanning) An electron microscope (SEM) was observed above the aluminum layer, and it was found that the small protrusions were completely suppressed and could not be produced, and a good cross-sectional structure was obtained.

1»The soil ik—firstly deposit a buffer aluminum layer with a film thickness of about 25 〇〇A on the glass substrate, and then deposit a film thickness of about 25 〇〇A, wherein the buffer (four) energy layer has a film thickness ratio of 1: 1, also anneal at a temperature of 34 (rc, time 3 〇 minutes, and then observe the top of the aluminum layer by scanning electron microscopy (SEM), the hair is suppressed and can not be produced, the bean is called the surface 钍 泸 泸 釭庶 釭庶 釭庶The over-etching of the aluminum layer by the over-etching of the aluminum layer results in an excessively long buffered aluminum layer. @, @, deposited a film thickness of $600 on the glass substrate. The slowness of A _ ^ / / film thickness is about 4500 A layer, J: middle, painted y ^ ^ ^ ^ ^ /, medium buffer aluminum layer and aluminum layer < film 厗 ratio is 1·_7·5, Annealing was also performed at a temperature of 34 〇χ and time deduction. 16 1246874 was observed by scanning electron microscopy (SEM) above the aluminum layer. After annealing, small protrusions were formed. This film thickness ratio could not completely relax the substrate and aluminum layer. The stress and the poor profile of the profile result in over-etching of the buffered aluminum layer. A test of a buffered aluminum layer with a thickness of about 750 is deposited on the glass substrate. , a re-deposited aluminum layer having a film thickness of about 4,500, wherein the buffer aluminum layer and the aluminum layer have a film thickness ratio of 1:6, and are also annealed at a temperature of 340 Å for 3 minutes, and then broom-type electrons The microscope (SεΜ) was observed above the inscription layer, and it was found that the small protrusions could be completely suppressed and could not be produced, and a good cross-sectional structure could be obtained. Experiment 22: A buffer aluminum layer with a film thickness of about 15 Å was deposited on the glass substrate. ^Re-deposited aluminum layer with a thickness of about 45 〇〇A, wherein the buffered aluminum layer and the aluminum layer have a thickness ratio of 1:3, and also annealed at a temperature of 340X for 30 minutes, and then an EW electron microscope (SEM) Observing the upper layer of the aluminum layer, it was found that the small protrusion could be suppressed and could not be produced, and a good cross-sectional structure could be obtained. On the glass substrate, a buffer aluminum layer with a film thickness of about 2250 A was deposited first, and the film thickness was further deposited. It is an aluminum layer of 4,500 people, wherein the buffered aluminum layer and the aluminum layer have a thickness ratio of 1:2, and are also annealed at a temperature of 340X for 30 minutes, and then viewed above the aluminum layer by a scanning electron microscope (SEM). It is found that the small protrusion can be completely suppressed and cannot be produced, and can be obtained well. Profile structure: Firstly, a buffer layer with a film thickness of about 4500 A is deposited on the glass substrate, and then an aluminum layer with a thickness of about 4500 A is deposited. The buffer aluminum layer and aluminum have a drought ratio of 1 _1. Annealing was carried out at a temperature of 340 ° C for 30 minutes, and then the upper layer of the aluminum layer was observed by a scanning electron microscope (SEM). It was found that the small protrusions could be used to make the king inhibited and could not be produced, but the cross-sectional structure was Due to the lack of etching of the inscription layer buffer layer, the buffer layer is too long. s Combining the above experiments, it is known that the metal layer of the Shaojin metal layer that does not have small protrusions includes: an embroidery type ^ exhibition 匕绍冲叙 ^ κ Formed on the substrate and the layer is formed above the retardation layer; wherein the thickness of the inscription layer is between 1_A and 4500 A, ^ the buffer! The layer can effectively inhibit the substrate and (4) the difference in thermal expansion coefficient, and the composition of the buffer layer can be nitrided (A丨

I Lu (ΑΙΟχ) or nitrogen-containing oxidation turns |〇)xNy), and the contact layer and the 33 layer: the ratio range is between 1:6~1:1. In addition, from a series of experiments in Table 2, it is known that a good profile (P_le) is required, and the thickness of the buffer layer is preferably smaller than the thickness of the layer; the mouth, layer = thickness is 1_A~4500 A Between, and the thickness ratio of the buffer layer and the layer is between about 1:6~1 __ 2 . Although in the above embodiment, a layer of the layer is used as an example, Mingya is not limited thereto, and may be two, three, four, five or more layers: as long as the glass substrate and (4) The effect of suppressing the j-bump can be achieved by buffering between the layers. Even in the case of continuous application, other elements may be added to the aluminum layer of the present invention. Moreover, regarding the buffer (4), it is also possible to combine the layers: for example, the first nitriding, the second nitriding, the second squirrel, which are formed by different nitrogen contents, the same due to different oxygen contents - Oxidation Ming, Second Oxidation, Third Oxidation, etc.; additionally, the first nitrogen-containing oxidation, the second nitrogen-containing oxidation, the third nitrogen-containing oxidation, etc., formed by different oxygen and nitrogen contents; Niobium Ming and Oxidation Ming, Nitrogen Ming and Nitrogen Oxidation Ming, Oxidation Ming and Rat Oxidation! S, nitriding (tetra) oxolane and nitrogen-containing oxidizing agent, the above three are combined with a multi-layer composite buffer aluminum layer. &quot; 18 1246874 The aluminum metal layer without the small protrusion disclosed in the above embodiments of the present invention has the advantages that the cost is greatly reduced compared with the conventional use of materials such as molybdenum or chromium, the process is simple, and the generation of small protrusions can be effectively suppressed. Therefore, it does not cause unevenness in the subsequent deposition of his layer, making the electronic characteristics of the element more stable.

The metal layer of the present invention having no aluminum sharpness can be applied to an electronic component as a conductive pattern such as an electrode, a wire or the like. Hereinafter, a thin film transistor is taken as an example to illustrate the application of the present invention to form a metal gate thereof. Figure 3 is a schematic cross-sectional view showing the bottom gate of a thin film transistor. First, a substrate 300 is provided, and a gate layer is deposited over the substrate 300, and the gate layer is patterned by lithography and etching to form a gate 310. Wherein, the deposition method of the gate layer is as described above, first depositing a buffer layer, and then depositing an aluminum layer over the buffer layer. Wherein, the thickness ratio of the buffer aluminum layer to the aluminum layer is in the range of about 1:6 to 1:2, and after the etching process, a good cross-sectional structure can be obtained. Next, a metal molybdenum (Mo) layer or a molybdenum nitride (MoN) layer is deposited over the aluminum layer to a thickness ranging from about 300 to about 1200 Å. A gate insulating layer 320 is then formed over the gate 310. Then, an amorphous layer 330 and an ohmic contact layer 340 are formed over the gate insulating layer 320 by a deposition, lithography, and silver etching process. Next, a dipole 360 and a source 365 are formed. The method comprises the steps of: depositing a metal layer, such as a metal such as chromium or aluminum, on the entire substrate 300, and patterning the metal layer by using a lithography and etching process, in the metal layer above the gate 'An opening is formed which exposes the amorphous layer 330. At this time, a dipole 360 and a source 365 are also formed. The drain 360 and the source 365 are separated by a channel. Then, a protective layer 370 is deposited over the entire substrate 300, and an opening is formed in the protective layer 370 by the lithography and etching steps to expose the drain 360. 19 1246874 Finally, a transparent electrode layer 380 overlies the protective layer 370 and fills the opening exposed to the drain 360. Similarly, the transparent electrode layer 380 is patterned by a lithography and etching process. In view of the fact that the types of electronic components are very diverse, and the thin film transistors have many different processes, the above is only one embodiment. Therefore, the method of applying the present invention as a gate is not limited to the above, and the method can be applied even. On the bungee and source metal layers. The electronic component produced by the invention not only has a large cost reduction, but also can effectively suppress the occurrence of small protrusions or aluminum protrusions, and the total resistance value thereof is lower than that of the conventional aluminum alloy. Electronic features are positive. The present invention has been described above by way of a preferred embodiment, and is not intended to limit the present invention. Any person skilled in the art can make various kinds without departing from the spirit and scope of the present invention. The scope of protection of the present invention is defined by the scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a schematic view showing a metal deposited on a glass substrate; FIG. 1B is a schematic view showing an annealed aluminum on a glass substrate; FIG. 2 is a view showing a preferred embodiment according to the present invention. A schematic diagram of suppressing the aluminum layer of the small bump; and FIG. 3 is a schematic cross-sectional view of the bottom panel of the thin film transistor. [Description of Drawings] 102, 202, 300: Substrate 104: Grain 20 1246874 106: Grain Boundary 110: Small bump or aluminum bump (Hillock) 204: Buffer Aluminum (Barrier Aluminum) Layer) 206: aluminum layer 310: gate 320: gate insulating layer 330: amorphous germanium layer 340: ohmic contact layer

360: bungee 365: source 370: protective layer 380: transparent electrode layer

twenty one

Claims (1)

1246874 picking up, claiming patent range: 1 · an aluminum metal layer without small bumps, forming at least two layers of aluminum layer on a substrate, the aluminum metal layer comprising: a buffer aluminum layer formed on the substrate; An inscription layer is formed over the buffer layer; wherein the thermal expansion coefficient (Thermal Expansjon Coefficient) of the buffer aluminum layer is smaller than a thermal expansion coefficient of the aluminum layer. 2. The metal layer as described in the scope of the patent application, wherein the buffer layer comprises at least aluminum nitride (A|Nx), aluminum oxide (A 丨〇χ) or nitrogen oxide containing aluminum (AlOxNy). 3. The application of the patent, the 金属 帛, the metal layer of the inscription, wherein the thickness of the layer is between 1QQQ A and 45QG A, and the thickness ratio of the buffer layer to the layer is about 1 : between 6 and 1:1. 4) An electronic component having a conductive pattern, wherein the conductive pattern comprises at least: a buffer aluminum layer formed on the substrate; and an aluminum layer formed over the buffer aluminum layer; wherein the buffer layer The Thermal Expansion Coefficient is less than the coefficient of thermal expansion of the aluminum layer. 5. The electronic component of claim 4, wherein the conductive pattern is an electrode pattern. The electronic component of claim 4, wherein the conductive pattern is a wire pattern. 7. The electronic component of claim 4, wherein the buffer layer comprises at least aluminum nitride (AINx), aluminum oxide (yttrium) or nitrogen-containing aluminum oxide (AlOxNy). 8. The electronic component according to claim 4, wherein the thickness of the aluminum layer is between 1 〇〇〇A and 4500 A, and the thickness ratio of the buffer layer to the thickness of the layer is about Between 1:6~1:2. 9. A method of fabricating an aluminum metal layer having no small bumps to avoid creating an uneven aluminum hillock, wherein the metal layer is on a substrate comprising at least two layers of aluminum, the fabrication The method comprises the steps of: forming a buffered aluminum layer on the substrate; and forming a layer above the buffer layer; wherein the thickness of the aluminum layer is between 彳000 A and 4500 A, and the thickness of the buffer aluminum layer The thickness ratio to the I layer is between about 1 and 1 · 1. The manufacturing method according to the above-mentioned item, wherein the thermal expansion coefficient (Thermal Expansicm CQefficient) of the buffer layer is smaller than a thermal expansion coefficient of the aluminum layer, but larger than a thermal expansion coefficient of the substrate. 〆11. The manufacturing method of claim 9, wherein the buffer layer comprises at least - nitriding (A|Nx), oxidizing (Α|〇χ) or containing nitrogen oxide (AlOxNy 卜) 23 1246874 12. A thin film transistor (Thinfilm transistor) element includes a base anti-gate layer disposed on a substrate, and a gate insulating layer, an amorphous layer, and an amorphous layer are sequentially deposited over the gate layer. An ohmic contact layer having a pass over the idler, and a metal layer on each side of the via as a source and a immersion, the source and the immersion covering the ohmic contact layer and the portion The substrate, the source and the drain are covered with a protective layer, wherein the gate is characterized by: a buffer-like layer and a layer of inscription, wherein the layer is formed in the slow Above the inscription layer, "inhibits the formation of the tip protrusion, and the thickness of the inscription layer is between 1000 Λ and 4500 λ, and the thickness ratio of the thickness of the buffer aluminum layer to the thickness of the aluminum layer is about 1:6~1 The thin film transistor component of claim 12, wherein the heat of the buffer aluminum layer The coefficient of expansion (Therma丨Expansi〇nc〇effjcient) is smaller than the coefficient of thermal expansion of the aluminum layer, but greater than the coefficient of thermal expansion of the substrate. 1 4. The thin film transistor element according to item 2 of the patent application, which is in the middle The buffered aluminum layer comprises at least an aluminum nitride (yttrium oxide), aluminum oxide (yttrium) or nitrogen-containing aluminum oxide (AlOxNy).