TW540160B - Schottky structure on GaAs semiconductor substrate - Google Patents

Abstract

The present invention provides a Schottky structure on GaAs semiconductor substrate, which comprises: a GaAs semiconductor substrate; a Ti metal layer distributed on the GaAs semiconductor substrate to form the Schottky contact; a diffusion barrier layer on the metal Ti layer to block the diffusion of metal layer; and a first Cu metal layer on the diffusion barrier layer. By using the diffusion barrier layer, the Cu metal in the subsequent process can be directly plated on the first Cu metal layer.

Description

MU16U V. Description of the Invention (l) Field of the Invention The present invention relates to a gallium arsenide (GaAs) semiconducting, port structure. Therefore, the present invention can be applied to the gallium element of Shishenhua and is easy to connect and cooperate with other processes. BACKGROUND OF THE INVENTION Currently, the Schottky structure of gallium arsenide (GaAs) S pieces is mainly composed of the structure of gold (Ti / Pt / Au), the metal titanium (Ti) layer is mainly formed, and the gallium carbide (GaAs) forms a Schottky contact. The metal platinum (pt) layer is the barrier layer, and the metal gold (Au) layer can reduce the overall structure of the structure. The structure of the transmission line of the gallium arsenide (GaAs) device is mainly gold. Compared with gold, it has more excellent electrical conductivity, heat dissipation, price and mechanical strength. If the problem of copper diffusion is overcome, copper is used as a strong metallization. Gold also makes the characteristics of the components more excellent. If gold (Au) is changed to copper (, the Schottky structure must also be modified to meet the needs of the copper process. 11 Kizahi Shimada et al. US Patent No. 5094 9 Document No. 54 · GaAs field effect semiconductor device having Schottky gate structure, which deposits a layer of titanium (Ti) metal on gallium (GaAs), and then deposits a layer of refractory metal and its nitride or carbide ' The present invention also deposits a layer of titanium (G aas) on GaAs T i) metal, and then deposit a diffusion barrier layer, which is a material of refractory metal; the different point of the present invention is the first metal 540160. 5. Description of the invention (2) The layer is distributed on the diffusion barrier layer. The advantage of this structure is that it can directly cooperate with the copper process and can further reduce the overall resistance of the Schottky structure.

Val erg M. Dubin et al., US Patent No. 5 6 5 8 10: Use of cobalt tungsten phosphide as a barrier material for copper metallization, using a metal layer of CoWP as a barrier layer to prevent copper diffusion; and The difference of the present invention is that the refractory metal and its nitride are used as a barrier layer to prevent copper diffusion. 81 (1 (1118 1'1: 113 811 (^ 11111 ^ et al. U.S. Patent No. 6 28844 9): Barrier f0r copper metal Hzation uses a multilayer structure of Ta / TaN / TiN as the diffusion barrier layer, and Different points of the present invention: ^ A single-layer refractory metal material is used as the diffusion barrier layer, which is more invented in the process: In view of this, the present invention provides a Schottky structure on a galvanized (GaAs) semiconductor. Metalized with copper The arsenic of the process is therefore a good base structure of the present invention. Another base structure of the present invention. Another main object of the present invention is to provide an object which is to provide a suitable purpose is to provide a steel with low resistance and heat dissipation, especially for high An overview of the structure of the Xiao metallization process of the frequency element used to connect to the other processes: Please refer to FIG. 1 m = the Schottky structure of a gallium arsenide (GaAs) semiconductor, including: a t-electron mobility transistor ( ΗΕMT) structure schematic s 2, metal copper + vacant ~ GaAs semiconductor substrate 1, Schottky structure, nitride 7, 结构 1 4 air 4 'metal copper layer 5, n-type gallium arsenide f its The copper metallization process of the component electrodes is mutually, Due to the lower resistance; ^ Ϊ The wire part has been changed from gold to copper, and households have benefited from the piano. P and good heat dissipation characteristics' Long component characteristics are greatly prepared for deep body hair; It can overcome the diffusion of steel into the GaN-based gallium monocrystalline microwave integrated circuit. Copper as a stone has good thermal and mechanical properties, good mechanical properties, etc. Low value, low cost, and component manufacturing. The level and level of gallium palladium can be improved. Detailed description and preferred embodiments. In order to achieve the above-mentioned object, paragraphs and specific structural features of the present invention, it is better to use the technical description of each wood to further reveal the details. As follows: Example, and borrow 540160 V. Description of the invention (4)

The invention provides a Schottky structure designed on a GaAs semiconductor; the purpose is to provide a copper metallization process required in industry or national defense. Please refer to FIG. 2. The present invention discloses a Schottky structure designed on a gallium arsenide (GaAs) semiconductor, which includes a semi-insulating gallium (GaAs) semiconductor substrate 1. A n-type gallium arsenide 8, distributed on the semi-insulating gallium arsenide (GaAs) semiconductor substrate 1; a metal titanium (Ti) layer 21, distributed on the n-type gallium KunAs (GaAs) 8, forming a Schottky contact; a diffusion barrier Layer 2 2 is distributed on the metal titanium (τ i) layer 21 to block the metal layer

A diffusion; a first metal copper (Cu) layer 23 is distributed on the diffusion barrier layer 22; the diffusion barrier layer 22 is used to solve the diffusion problem of the first metal copper (Cu) layer 23; Subsequent copper processes are directly plated on this structure. Figure 3 is a schematic diagram of a conventional gallium gallium structure, including: one stone applied to one metal titanium (Ti) layer 31, distributed over 30 to form a Schottky contact, on top of the metal titanium (Ti) layer 31, The (Au) layer 33 'is distributed over the metal. When the component is used in the copper process, it is changed from gold to copper metal. Therefore, if the metal layer on the surface is gold, a barrier layer is plated in order to prevent the Schottky structured gallium (G) on the gold (GaAs) semiconductor. a A s) semiconductor substrate 30, on a gallium arsenide (GaAs) semiconductor substrate-a metal platinum (Pt) layer 32, distributed to form a diffusion barrier layer, a metal gold (Pt) layer 'forms a Schottky structure, and the metal contacts Wires and air bridges are all shown in Figure 3. As far as the conventional Schottky structure is concerned, the right side must be in contact with the copper wire and must diffuse through the copper.

The Schottky structure of the present invention enables direct plating of subsequent copper metal processes

:) Arsenic UiOU V. Description of the invention (5) Schematic diagram of the structure of the Schottky structure i, including ^ Figure ^ shows the preferred embodiment of the present invention is a titanium (metal) layer ^ I gallium (GaAS) semiconductor substrate 30. A gold-based contact is formed: a titanium (Ti) layer 31 on a gallium arsenide (GaAs) semiconductor substrate 31 has a diffusion barrier layer 321, and is distributed on the metal copper (Cu) layer 34. Diffusion of the metal layer; a first metal Schottky structure, it is possible: the diffusion barrier layer 321 is formed to form a further vapor warehouse, and the copper process is directly plated on the structure. The 31 series are distributed in U, γ and δ as shown in FIG. 4; the metal titanium (HaAs layer made of samarium layer nm to 100nmR) semiconductor substrate 30 has a thickness of 50: the German I process uses sputtering or evaporation. The diffusion barrier layer body 1 is distributed on the metal titanium (Ti) | ". The invention uses Yan (w), tungsten (WN), cobalt (Co), button (Ta), tantalum nitride (Ta N or titanium) (Mo) and other refractory metal materials replace the traditional metal platinum (pt) as the diffusion P early barrier layer 3 21, the thickness of which is between 3.0 and 100 nm, the first metallic copper (Cu) layer 34 is the uppermost layer Distributed on the diffusion barrier layer 3 2 1 'Replace traditional metallic gold with metallic copper, with a thickness between 2000 nm and 500 nm. Because tungsten (w), cobalt (Co), molybdenum (Mo) and other refractory metals Compared with platinum metal (pt), the material has a lower resistance value, and it is not easy to react with metal copper. In addition, metal copper also has a lower resistance value and better thermal conductivity than metal gold. When the component is changed to the copper process, this structure can be directly combined with the copper process. Since the overall resistance value of the present invention is at the same thickness, the resistance value is lower than that of the traditional structure shown in Figure 3. Therefore, the device characteristics can be greatly improved. , For a reasonable and perfect creation 'not only has excellent practicality, but also in design 54016 0 V. Description of the invention (6) It is an unprecedented innovation and novelty. The general structure shown in Figure 3 is deposited by evaporation. If the sputtering method is used, the surface temperature of the wafer during coating is lower than The shape of the photoresist is not easy to break. The diffusion barrier layer 3 2 1 of the present invention is deposited on the ore by sputtering. The metal titanium (Ti) layer 31 and the first metal copper (Cu) layer 3 4 are formed by sputtering or When the component is used in the copper process, the structure is generally shown in Figure 3. The top surface metal gold layer 3 3 must be plated with a barrier layer in the middle to contact the copper wire to prevent gold and copper. Diffusion, a Schottky structure on a gallium arsenide (GaAs) semiconductor according to the present invention can enable subsequent copper metal processes to be directly plated on the gate electrode, which is not only a reasonable and perfect creation, but also a highly invented breakthrough of the conventional technology In summary, this case has already met the various application requirements for invention patents, and I urge you to investigate them in detail and grant the patents you deserve. It is really a prayer. Although the present invention has been compared with The foregoing descriptions, they are not intended to limit the invention by any person familiar with this art, the present invention without departing from the spirit and scope, as modifications and variations do little of, and therefore the present

540160 Schematic illustrations Schematic illustrations Figure 1 is a schematic diagram of a high electron mobility transistor (HEMT) structure; Figure 2 is a schematic diagram of a Schottky structure of the present invention; Figure 3 is a conventional gallium arsenide (GaAs) semiconductor The structure of the above-mentioned Schottky structure is not intended, and FIG. 4 is a schematic structural diagram of a preferred embodiment of the present invention;

Semi-Insulated Kunhua Semiconductor Substrate ----- 1 Schottky Structure ------------------- 2 Metal Copper Air Bridge ---------- ----- 3 Air ----------------------- 4 Metal copper layer ---------------- --- 5 η-type gallium arsenide ----------------- 6 nitride -------------------- -7 gallium arsenide semiconductor substrate ----------- 30 metal titanium (Ti) layer ------------- 2b 31 metal port (Pt) layer --- ---------- 32 Metal gold (Au) layer ------------- 33 Diffusion barrier layer ---------------- -22, 321 The first metallic copper (Cu) layer --------- 23, 34

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Claims (1)

540160 6. Scope of patent application 1. A structure on a gallium arsenide (GaAs) semiconductor, including: a KunAs semiconductor substrate, a metal titanium (Ti) layer, distributed on the deification plate, Forming a Schottky contact; a diffusion barrier layer distributed over the metal titanium (blocking metal diffusion layer); and a first metal copper (Cu) layer distributed over the forming Schottky structure; through the diffusion barrier layer (Cu ) The metal process is directly plated on the first metal 2. The Schottky structure of a conductor as described in item 1 of the scope of patent application, wherein the titanium metal (is between 50 nm and 100 nm. 3. If applying for a patent The Schottky structure on a conductor according to item 1 in the scope, wherein metal titanium (sputtering or evaporation method. 4. The Schottky structure on a conductor as described in item 1 in the patent application scope, wherein the diffusion barrier ( W), tungsten nitride (WN), cobalt (Co), tantalum, (TaN), or molybdenum (Mo) and other refractory metals 4 5. A Schottky structure on a conductor as described in item 1 of the scope of patent application, in which diffusion Obstacle or vapor deposition method 6. As described in item 1 of the scope of patent application A d-based (Schottky) gallium (GaAs) semiconductor-based Ti) layer is used on the diffusion barrier layer so that subsequent copper-copper (Cu) layers can be made. ) Layer with a thin film thickness of L Shishen Hualu (GaAs) half Ti) layer process uses L Shishen Hua Su (G a As s) half layer material, which is selected from tungsten button (Ta), nitride By.石 Shi Shenhua's (GaAs) half-layer process system uses sputtered L-GaAs half-540160 6. Patent-based structure on the conductor, in which the thickness of the diffusion barrier film is 30 nm to 10 Between 0 nm. 7. The Schottky structure on a gallium arsenide (GaAs) semiconductor as described in item 1 of the scope of patent application, wherein the thickness of the first metal copper (Cu) layer film is between 200 nm and 350 nm. between. 8. A Schottky structure on a gallium arsenide (GaAs) semiconductor as described in item 1 of the scope of the patent application, wherein the first metal copper (Cu) layer is fabricated by sputtering or evaporation. Page 12