CN104752182B - A method of making NiSiGe material using Ti insertion layer - Google Patents

Abstract

The present invention provides a method for making NiSiGe material by using a Ti insertion layer, which at least includes the following steps: 1) providing a Si _{1- x} Ge _x layer, and forming a Ti metal film on the surface of the Si _1-x Ge _x layer, wherein, 0.05≤x≤0.9; 2) forming a Ni metal layer on the surface of the Ti-doped layer; 3) using a rapid annealing process to make the Ni metal pass through the Ti metal thin film to react with the Si _1-x Ge _x layer A NiSi _1-x Ge _x layer is generated, where 0.05≤x≤0.9. The present invention has the following beneficial effects: due to the specific temperature, the thermal activation energy required for the reaction of Ni with the Si _{1- x} Ge _x layer can be provided, and only a very small amount of Ti can react with the Si _1-x Ge _x and be kept at the Si ₁ -x Ge x level. At the interface between the _x Ge _x layer and the NiSi _{1‑ x} Ge _x layer, several atomic layers of defect accumulation areas are generated, which block the release of the surface film stress from the transfer to the bottom layer, and at the same time enable the reaction between Ni and Si _1‑x Ge _x . Do it at a slower pace. Therefore, the present invention plays a certain role in maintaining the strain of Si _1-x Ge _x , and a continuous, uniform and stable NiSiGe material can be obtained.

Description

A method of making NiSiGe material using Ti insertion layer

technical field

The present invention relates to a method for fabricating a semiconductor device, in particular to a method for fabricating NiSiGe material using a Ti insertion layer.

Background technique

In the source and drain regions of traditional transistors, the electrodes generally use direct contact between semiconductor and metal electrodes, and the contact resistance is large, resulting in a high Schottky barrier, which affects the performance of the device. Therefore, people are constantly looking for a method that can reduce the contact resistance of electrodes, in which a structure with good effect basically completely replaces the technology of direct contact between semiconductor and metal electrodes. This structure with good effect is made of metal and Si materials. The reaction generates metal silicide as a contact material, which can greatly reduce the contact resistance and Schottky barrier, and has been widely used. Later, the metal elements of metal silicides went through the development process from Ti to Co, and then to Ni. And Ni silicide has been widely used due to its excellent performance and good processing technology. At present, NiSi is used as the contact material in the source and drain regions of MOSFET transistors produced by manufacturers such as Intel and AMD.

With the advancement of semiconductor materials and processes, Si _1-x Ge _x , as a new type of high mobility material, is an important supplement to Si materials in the future. However, when Ni and Si _1-x Ge _x undergo an alloying reaction, since Ge and Si and Ge will generate silicides and germanides with different reaction heats, it is easy to cause inconsistent reaction sequences of Ni, Si, and Ge atoms. It is easy to form continuous, uniform and stable NiSi _1-x Ge _x thin films. In addition, due to the precipitation and diffusion of Ge, excessive grain boundaries eventually lead to poor electrical properties of the formed NiSi _1-x Ge _x film, which largely affects the application of the NiSi _1-x Ge _x film as a source-drain contact.

In view of the above shortcomings, the purpose of the present invention is to provide a method for producing continuous, uniform and stable Ni Si _1-x Ge _x materials.

SUMMARY OF THE INVENTION

In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a method for making NiSiGe materials by using a Ti insertion layer, which is used to solve the problem that it is not easy to form continuous, uniform and stable Ni(Si _1-x ) in the prior art. Ge _x ) material problem.

In order to achieve the above-mentioned purpose and other related purposes, the present invention provides a method for making NiSiGe material by utilizing Ti insertion layer, which at least comprises the following steps:

1) Provide a Si _1-x Ge _x layer, and form a Ti metal film on the surface of the Si _1-x Ge _x layer, wherein 0.05≤x≤0.9;

2) forming a Ni metal layer on the surface of the Ti metal film;

3) Using a rapid annealing process, the Ni metal passes through the Ti metal thin film and reacts with the Si _1-x Ge _x layer to form a NiSi _1-x Ge _x layer, where 0.05≤x≤0.9.

As a preferred solution of the method for producing a NiSiGe material using a Ti insertion layer of the present invention, in the reaction process of step 3), a TiNiSi _1-x Ge _x layer and a non-ferrous oxide layer will also be formed on the surface of the NiSi _1-x Ge _x layer. crystalline thin film, wherein, 0.05≤x≤0.9.

Further, the method further includes the step of: removing the amorphous thin film by a selective etching process.

As a preferred solution of the method for producing NiSiGe material by using a Ti insertion layer of the present invention, the annealing temperature range of the rapid annealing process is 300-800°C.

As a preferred solution of the method for producing NiSiGe material by using the Ti insertion layer of the present invention, the annealing time of the rapid annealing process ranges from 30 to 120 s.

As a preferred solution of the method for producing a NiSiGe material using a Ti insertion layer of the present invention, the thickness of the Ti metal thin film is 1-5 nm.

As a preferred solution of the method for producing a NiSiGe material by using a Ti insertion layer of the present invention, the thickness of the Ni metal layer is 5-100 nm.

As a preferred solution of the method for producing a NiSiGe material using a Ti insertion layer of the present invention, the Ti metal thin film and the Ni metal layer are formed by an evaporation process or a sputtering process.

As a preferred solution of the method for producing NiSiGe material by using the Ti insertion layer of the present invention, the Si _{1- x} Ge _x layer is epitaxially formed on the surface of the silicon substrate.

As described above, the present invention provides a method for making NiSiGe material using a Ti insertion layer, which at least includes the following steps: 1) providing a Si _1-x Ge _x layer, and forming Ti metal on the surface of the Si _1-x Ge _x layer film, wherein, 0.05≤x≤0.9; 2) a Ni metal layer is formed on the surface of the Ti-doped layer; 3) a rapid annealing process is used to make the Ni metal pass through the Ti metal film and the Si _1-x The Ge _x layer reacts to form a NiSi _1-x Ge _x layer, where 0.05≤x≤0.9. The present invention has the following beneficial effects: due to the specific temperature, the thermal activation energy required for the reaction of Ni with the Si _1-x Ge _x layer can be provided, and only a very small amount of Ti can react with the Si _{1- x} Ge _x and remain at the Si _1- x Ge x . At the interface between the _x Ge _x layer and the NiSi _1-x Ge _x layer, several atomic layers of defect accumulation areas are generated, which block the release of the surface film stress and transfer to the bottom layer, and at the same time make the reaction between Ni and Si _1-x Ge _x . Do it at a slower pace. Therefore, the present invention plays a certain role in maintaining the strain of Si _1-x Ge _x , and can obtain a continuous, uniform and stable NiSiGe material.

Description of drawings

1 to 2 are schematic structural diagrams presented in step 1) of the method for fabricating a NiSiGe material by using a Ti insertion layer of the present invention.

FIG. 3 shows a schematic structural diagram of step 2) of the method for fabricating NiSiGe material by using a Ti insertion layer of the present invention.

4 to 5 are schematic structural diagrams presented in step 3) of the method for fabricating NiSiGe material by using a Ti insertion layer of the present invention.

Component label description

101 Silicon substrate

102 Si _1-x Ge _x layer

103 Ti metal film

104 Ni metal layer

105 NiSi _1-x Ge _x layer

106 TiNiSi _1-x Ge _x layer

107 Amorphous thin film

Detailed ways

The embodiments of the present invention are described below through specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

Please refer to Figure 1 to Figure 5. It should be noted that the diagrams provided in this embodiment are only to illustrate the basic concept of the present invention in a schematic way, and the drawings only show the components related to the present invention rather than the number, shape and number of components in actual implementation. For dimension drawing, the type, quantity and proportion of each component can be arbitrarily changed in actual implementation, and the component layout may also be more complicated.

As shown in FIG. 1 to FIG. 5 , this embodiment provides a method for fabricating NiSiGe material by using a Ti insertion layer, which at least includes the following steps:

As shown in FIGS. 1 to 2 , step 1) is first performed, a Si _1-x Ge _x layer 102 is provided, and a Ti metal film 103 is formed on the surface of the Si _1-x Ge _x layer 102 , wherein 0.05≤x≤ 0.9.

As an example, a silicon substrate 101 is first provided, an epitaxial process is used to form a Si _1-x Ge _x layer 102 with stress on the surface of the silicon substrate 101, and then an evaporation process or a sputtering process is used to form the Si ₁ -x Ge x layer 102 on the surface of the silicon substrate 101. A Ti metal thin film 103 _is formed on the surface of the _xGex layer 102. In this embodiment, the thickness of the Ti metal thin film 103 is 1˜5 nm.

As shown in FIG. 3 , then step 2) is performed to form a Ni metal layer 104 on the surface of the Ti metal thin film 103 .

As an example, a Ni metal layer 104 is formed on the surface of the Ti metal thin film 103 by an evaporation process or a sputtering process, and the thickness of the Ni metal layer 104 is 5-100 nm.

As shown in FIG. 4 , step 3) is finally performed, and a rapid annealing process is used to make the Ni metal pass through the Ti metal film 103 and react with the Si _1-x Ge _x layer 102 to form a NiSi _1-x Ge _x layer 105 , where 0.05≤x≤0.9.

As an example, the above structure is subjected to rapid annealing at a temperature of 300-800°C, and the annealing time of the rapid annealing is 30s-120s, so that the Ni metal passes through the Ti metal film 103 and the Si _1-x The Ge _x layer reacts to form a NiSi _1-x Ge _x layer 105 , where 0.05≦x≦0.9. The specific process is that in the process of rapid annealing, since the temperature is 300-800 °C, it is sufficient to provide the thermal activation energy required for the reaction of Ni and Si _1-x Ge _x layers, but has not yet reached the level of Ti and Si _1-x Ge _x . Therefore, only a very small amount of Ti will react with the Si _1-x Ge _x layer, and the thickness of the Ti metal film 103 is small, and Ni metal can pass through the Ti metal film 103 and interact with the layer. The Si _1-x Ge _x layer reacts to form the NiSi _1-x Ge _x layer 105, and the reaction speed is relatively slow, and finally a continuous, uniform and stable NiSiGe material can be obtained.

In addition, as shown in FIG. 4 , in the reaction process of step 3), a TiNiSi _1-x Ge _x layer 106 (0.05≤x≤0.9) and an amorphous layer may also be formed on the surface of the NiSi _1-x Ge _x layer 105 The thin film 107, even a small amount of Ti metal thin film 103 remains, the TiNiSi _1-x Ge _x layer 106 and a small amount of Ti metal thin film 103 have little effect on the performance of the NiSiGe material, which can be retained or can be selectively corroded process, and the amorphous film 107 has a great influence on the performance of the NiSiGe material, so in this embodiment, the step of removing the amorphous film 107 by a selective etching process is also included, as shown in FIG. 5 .

In a specific application process, the Si _1-x Ge _x layer 102 is a Si _0.95 Ge _0.05 layer, the thickness of the Ti metal film 103 is 1 nm, and the thickness of the Ni metal layer 104 is 5 nm. The annealing temperature was 300 °C and the annealing time was 30 s to obtain NiSi _0.95 Ge _0.05 material with good properties.

In another specific application process, the Si _1-x Ge _x layer 102 is a Si _0.5 Ge _0.5 layer, the thickness of the Ti metal film 103 is 3 nm, and the thickness of the Ni metal layer 104 is 50 nm. The annealing temperature is 600 °C and the annealing time is 60 s to obtain NiSi _0.5 Ge _0.5 material with good properties.

In another specific application process, the Si _1-x Ge _x layer 102 is a Si _0.1 Ge _0.9 layer, the thickness of the Ti metal film 103 is 5 nm, and the thickness of the Ni metal layer 104 is 100 nm. The annealing temperature is 800 °C and the annealing time is 120 s to obtain NiSi _0.1 Ge _0.9 material with good properties.

As described above, the present invention provides a method for making NiSiGe material using a Ti insertion layer, which at least includes the following steps: 1) providing a Si _1-x Ge _x layer, and forming Ti metal on the surface of the Si _1-x Ge _x layer film 103, wherein, 0.05≤x≤0.9; 2) forming a Ni metal layer 104 on the surface of the Ti-doped layer; 3) using a rapid annealing process to make the Ni metal pass through the Ti metal film 103 and the Si The _{1- xGex} layer 102 reacts to form a NiSi _{1- xGex} layer 105, wherein 0.05≤x≤0.9. The present invention has the following beneficial effects: due to the specific temperature, the thermal activation energy required for the reaction of Ni with the Si _1-x Ge _x layer can be provided, and only a very small amount of Ti can react with the Si _1-x Ge _x and remain at the Si ₁ -x Ge x level. At the interface between the _x Ge _x layer and the NiSi _1-x Ge _x layer, several atomic layers of defect accumulation areas are generated, which block the release of the surface film stress and transfer to the bottom layer, and at the same time make the reaction between Ni and Si _1-x Ge _x . Do it at a slower pace. Therefore, the present invention plays a certain role in maintaining the strain of Si _1-x Ge _x , and can obtain a continuous, uniform and stable NiSiGe material. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial application value.

The above-mentioned embodiments merely illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed in the present invention should still be covered by the claims of the present invention.

Claims (8)

1. a method utilizing Ti insertion layer to make NiSiGe material, is characterized in that, comprises the following steps at least: 1) A Si _1-x Ge _x layer is provided, and a Ti metal film is formed on the surface of the Si _1-x Ge _x layer, and the thickness of the Ti metal film is 5 nm, wherein 0.05≤x≤0.9; 2) forming a Ni metal layer on the surface of the Ti metal film; 3) Using a rapid annealing process to make the Ni metal pass through the Ti metal thin film to react with the Si _1-x Ge _x layer to form a NiSi _1-x Ge _x layer, where 0.05≤x≤0.9. 2. The method according to claim 1, wherein in the reaction process of step 3), TiNiSi _1-x Ge is also formed on the surface of the NiSi _{1-x Ge} layer. The _x layer and the amorphous film, wherein, 0.05≤x≤0.9. 3 . The method for making NiSiGe material by using Ti insertion layer according to claim 2 , further comprising the step of: removing the amorphous film by a selective etching process. 4 . 4 . The method according to claim 1 , wherein the annealing temperature of the rapid annealing process ranges from 300°C to 800°C. 5 . 5 . The method according to claim 4 , wherein the annealing time of the rapid annealing process ranges from 30 to 120 s. 6 . 6 . The method according to claim 1 , wherein the thickness of the Ni metal layer is 5-100 nm. 7 . 7 . The method of claim 1 , wherein the Ti metal thin film and the Ni metal layer are formed by an evaporation process or a sputtering process. 8 . 8 . The method according to claim 1 , wherein the Si _{1- x} Ge _x layer is epitaxially formed on the surface of the silicon substrate. 9 .

Images