CN104810280A - Semiconductor device manufacturing method - Google Patents

Abstract

The invention discloses a method for manufacturing a semiconductor device, comprising the following steps: adopting a front-end process for a substrate of a semiconductor device, wherein the front-end process is a collection of processes required for manufacturing a semiconductor device; Treated substrates are subjected to the first hydrogen annealing process. The manufacturing method of the semiconductor device of the invention reduces the density of dangling bonds and improves the quality of the semiconductor device.

Description

Manufacturing method of semiconductor device

technical field

The invention relates to the field of semiconductor devices, in particular to a method for manufacturing a semiconductor device.

Background technique

Semiconductor device manufacturing is to fabricate integrated components on semiconductor substrates and connect integrated components. Commonly used semiconductor substrate materials include single crystals such as silicon and germanium, and compound semiconductors such as gallium nitride; among them, single crystal silicon is the most commonly used semiconductor substrate material.

A manufacturing method of a semiconductor device includes a front-end process and a back-end process. The front-end process is a collection of processes required for the substrate to manufacture semiconductor devices; it mainly includes the process of defining the working area and field area on the substrate, and the process of making structures such as N-type doped regions, P-type doped regions, and contact holes. . The backend process includes a metal layer process for fabricating a metal layer, wherein the metal layer includes a metal interconnection structure through which the integrated components are connected. For semiconductor devices with complex functions, the metal layer includes a multi-layer metal interconnection structure, the metal interconnection structures of adjacent layers are insulated by silicon oxide, and the metal interconnection structures of the same layer are insulated by silicon oxide. The post-stage process also includes various processes after the metal layer process, such as the passivation layer process for making a passivation layer, where the passivation layer is mainly used for the protection of semiconductor devices, and the passivation layer structure generally includes silicon oxide film and nitride Overlay of silicon film layers.

In the actual process, there are a large number of dangling bonds on the surface of the substrate. The so-called dangling bonds are unsaturated ionic bonds (no valence bonds with oxygen atoms or other atoms). The dangling bond has many adverse effects on the semiconductor device, such as affecting the accuracy of the semiconductor device, affecting the reliability of the semiconductor device, and the like. In order to reduce the density of dangling bonds on the surface of the substrate, the most commonly used method is to use hydrogen annealing process to allow some hydrogen atoms to reach the surface of the substrate through high temperature diffusion and combine with dangling bonds, thereby reducing the dangling bonds on the surface of the semiconductor substrate. The purpose of bond density. In the prior art, the hydrogen annealing process is implemented after the passivation layer process, and its high-temperature process also has a certain effect on the combination (that is, alloying) of the metal and the substrate, so the hydrogen annealing process in the prior art is also called alloy process.

Hydrogen atoms can diffuse into silicon oxide and move in it, but they cannot diffuse through the silicon nitride film layer in the passivation layer structure, nor can they diffuse through the metal layer. For semiconductor devices with a silicon nitride film layer in the passivation layer, because the passivation layer covers a large area on the surface of the semiconductor device and only opens several small dimensions (such as 90 microns × 90 microns) at the set position The film layer of the window, and the surface layer of the window area is a metal layer structure, so the hydrogen annealing process is performed after the passivation layer, and the hydrogen atoms in the hydrogen annealing process cannot diffuse through the surface layer structure (the window area is a metal layer, outside the window The area of the passivation layer) reaches the surface of the substrate. The main mechanism of the hydrogen annealing process after the passivation layer to reduce the dangling bond density on the substrate surface is to drive the hydrogen atoms in the silicon nitride film layer to penetrate into the silicon oxide and diffuse to the substrate surface to combine with the dangling bonds. The hydrogen atoms in the film layer are left in the film layer during the chemical vapor deposition growth process of the silicon nitride film layer. However, the sufficiency of the hydrogen atoms produced by this mechanism to bond with the dangling bonds on the substrate surface is not high, resulting in the failure of semiconductor devices containing silicon nitride film layers in the passivation layer of the prior art to achieve high precision and high reliability. Sexual semiconductor device requirements. If a passivation layer including a silicon nitride film layer with superior protection effect is not used in order to improve the degree of eliminating dangling bonds, it will result in insufficient protection of the semiconductor device.

Contents of the invention

The invention provides a manufacturing method of a semiconductor device, which reduces the density of dangling bonds and improves the quality of the semiconductor device.

To achieve the above object, the present invention provides the following technical solutions:

A method for manufacturing a semiconductor device, comprising the steps of:

Using a front-end process for the substrate of the semiconductor device, wherein the front-end process is a collection of processes that need to be used on the substrate to manufacture the semiconductor device;

The first hydrogen annealing process is adopted for the substrate processed by the previous process.

Preferably, the manufacturing method of the semiconductor device also includes the following steps:

forming a metal layer on the substrate treated by the first hydrogen annealing process, wherein the metal layer includes a metal interconnection structure and silicon oxide other than the metal interconnection structure;

A second hydrogen annealing process is applied to the substrate including the metal layer.

Preferably, the manufacturing method of the semiconductor device also includes the following steps:

forming a passivation layer on the substrate including the metal layer treated by the second hydrogen annealing process;

A third hydrogen annealing process is applied to the substrate including the passivation layer and the metal layer.

Preferably, the process temperature of the first hydrogen annealing process is 200-700 degrees Celsius, and the gas of the first hydrogen annealing process is hydrogen or a mixed gas of hydrogen and an inert gas that does not react with it.

Preferably, the process temperature of the second hydrogen annealing process is 200-475 degrees Celsius, and the gas used in the second hydrogen annealing process is hydrogen or a mixed gas of hydrogen and an inert gas that does not react with it.

Preferably, the process temperature of the third hydrogen annealing process is 200-475 degrees Celsius, and the gas used in the third hydrogen annealing process is hydrogen or a mixed gas of hydrogen and an inert gas that does not react with it.

Preferably, the metal layer includes a layer of metal interconnection structure, and the metal interconnection structure is insulated by silicon oxide.

Preferably, the metal layer includes a multi-layer metal interconnection structure, the metal interconnection structures of adjacent layers are insulated by silicon oxide, and the metal interconnection structures of the same layer are insulated by silicon oxide.

Preferably, the passivation layer is a stacked layer comprising a silicon oxide film layer and a silicon nitride film layer.

Preferably, the front-end process includes but not limited to the process of defining the working area and the field area on the substrate, and the process of manufacturing N-type doped regions, P-type doped regions and contact holes.

In the manufacturing method of the semiconductor device provided by the present invention, after adopting the front-stage process to the substrate, the first-time hydrogen annealing process is directly applied to the substrate treated by the previous-stage process, and the hydrogen atoms in the first-time hydrogen annealing process do not have any barriers, It can easily reach the surface of the substrate and combine with the dangling bonds on the surface of the substrate, reducing the density of the dangling bonds and improving the quality of semiconductor devices.

Description of drawings

Fig. 1 is the flowchart of the first embodiment of the manufacturing method of semiconductor device of the present invention;

Fig. 2 is the flowchart of the second embodiment of the manufacturing method of semiconductor device of the present invention;

FIG. 3 is a flowchart of a third embodiment of the method of manufacturing a semiconductor device of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The manufacturing method of the semiconductor device of first embodiment of the present invention, as shown in Figure 1, comprises the steps:

Step 101: Applying a front-end process to the substrate of the semiconductor device, wherein the front-end process is a collection of processes that need to be used on the substrate to manufacture the semiconductor device;

Step 102: Applying the first hydrogen annealing process to the substrate treated by the previous process.

In the manufacturing method of the semiconductor device of this embodiment, after the substrate is subjected to the previous stage process, the first hydrogen annealing process is directly applied to the substrate processed by the previous stage process, and the hydrogen atoms in the first hydrogen annealing process are not blocked by any means. It can easily reach the surface of the substrate and combine with the dangling bonds on the surface of the substrate, reducing the density of the dangling bonds and improving the quality of semiconductor devices.

The manufacturing method of the semiconductor device of the second embodiment of the present invention, as shown in Figure 2, after the step 102 of the first embodiment, also includes the following steps:

Step 201: forming a metal layer on the substrate treated by the first hydrogen annealing process, wherein the metal layer includes a metal interconnection structure and silicon oxide other than the metal interconnection structure;

Step 202: Applying a second hydrogen annealing process to the substrate formed with the metal layer.

The second hydrogen annealing process is adopted for the substrate including the metal layer. The metal layer includes the metal interconnection structure and the silicon oxide outside the metal interconnection structure. The second hydrogen annealing process can penetrate the hydrogen atoms outside the metal interconnection structure. Silicon oxide is diffused to the surface of the substrate and combined with dangling bonds, which further reduces the density of dangling bonds and improves the quality of semiconductor devices.

The manufacturing method of the semiconductor device of the third embodiment of the present invention, as shown in Figure 3, after the step 201 of the second embodiment, also includes the following steps:

Step 301: forming a passivation layer on the substrate including the metal layer treated by the second hydrogen annealing process;

Step 302: Apply a third hydrogen annealing process to the substrate including the passivation layer and the metal layer.

The third hydrogen annealing process results in better bonding of the metal to the substrate.

Specifically, the process temperature of the first hydrogen annealing process in step 102 is 200-700 degrees Celsius, and the gas used in the first hydrogen annealing process is hydrogen or a mixed gas of hydrogen and an inert gas that does not react with it. A higher temperature can be used in the first hydrogen annealing process to increase the ratio of hydrogen atoms in the first hydrogen annealing process penetrating into silicon oxide and diffusing to the substrate surface to bind with dangling bonds, further reducing the density of dangling bonds, The quality of semiconductor devices is improved.

Specifically, the process temperature of the second hydrogen annealing process in step 202 is 200-475 degrees Celsius, and the gas used in the second hydrogen annealing process is hydrogen or a mixed gas of hydrogen and an inert gas that does not react with it. Considering the melting point of the metal layer and the influence of high temperature on the metal layer, the process temperature of the second hydrogen annealing process cannot exceed 475 degrees Celsius.

Specifically, the process temperature of the third hydrogen annealing process in step 302 is 200-475 degrees Celsius, and the gas used in the third hydrogen annealing process is hydrogen or a mixed gas of hydrogen and an inert gas that does not react with it.

As an optional manner, the metal layer includes a layer of metal interconnection structure, and the metal interconnection structure is insulated by silicon oxide.

As an optional manner, the metal layer includes a multi-layer metal interconnection structure, the metal interconnection structures of adjacent layers are insulated by silicon oxide, and the metal interconnection structures of the same layer are insulated by silicon oxide.

As a preferred manner, the passivation layer is a stacked layer including a silicon oxide film layer and a silicon nitride film layer. In the third hydrogen annealing process, the hydrogen atoms in the silicon nitride film layer penetrate into the silicon oxide and diffuse to the substrate surface to combine with dangling bonds, further reducing the density of dangling bonds and improving the quality of semiconductor devices.

Specifically, the front-end process includes, but is not limited to, the process of defining the working area and the field area on the substrate; the process of manufacturing N-type doped regions, P-type doped regions and contact holes.

Apparently, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (10)

1. A method for manufacturing a semiconductor device, comprising the steps of: Using a front-end process for the substrate of the semiconductor device, wherein the front-end process is a collection of processes that need to be used on the substrate to manufacture the semiconductor device; The first hydrogen annealing process is adopted for the substrate processed by the previous process. 2. The method for manufacturing a semiconductor device according to claim 1, further comprising the steps of: forming a metal layer on the substrate treated by the first hydrogen annealing process, wherein the metal layer includes a metal interconnection structure and silicon oxide other than the metal interconnection structure; A second hydrogen annealing process is applied to the substrate including the metal layer. 3. The method for manufacturing a semiconductor device according to claim 2, further comprising the steps of: forming a passivation layer on the substrate including the metal layer treated by the second hydrogen annealing process; A third hydrogen annealing process is applied to the substrate including the passivation layer and the metal layer. 4. The method for manufacturing a semiconductor device according to claim 1, 2 or 3, wherein the process temperature of the hydrogen annealing process for the first time is 200 to 700 degrees Celsius, and the gas of the hydrogen annealing process for the first time It is a mixed gas of hydrogen or hydrogen and an inert gas that does not react with it. 5. The manufacturing method of a semiconductor device according to claim 2 or 3, wherein the process temperature of the hydrogen annealing process for the second time is 200 to 475 degrees Celsius, and the gas of the hydrogen annealing process for the second time is hydrogen or hydrogen and its A mixture of nonreactive inert gases. 6. The manufacturing method of a semiconductor device according to claim 3, wherein the process temperature of the third hydrogen annealing process is 200 to 475 degrees Celsius, and the gas of the third hydrogen annealing process is hydrogen or hydrogen and does not react with it A mixture of inert gases. 7. The method for manufacturing a semiconductor device according to claim 2 or 3, wherein the metal layer comprises a layer of metal interconnection structure, and the metal interconnection structure is insulated by silicon oxide. 8. The manufacturing method of a semiconductor device according to claim 2 or 3, wherein the metal layer comprises a multilayer metal interconnection structure, and the metal interconnection structures of adjacent layers are insulated by silicon oxide, and the same layer The metal interconnect structure is insulated by silicon oxide. 9. The method for manufacturing a semiconductor device according to claim 3, wherein the passivation layer is a stacked layer comprising a silicon oxide film layer and a silicon nitride film layer. 10. The manufacturing method of a semiconductor device according to claim 9, characterized in that, the front-end process includes but not limited to the process of defining a working area and a field area on the substrate, making an N-type doped area, a P-type doped area, etc. Miscellaneous region and contact hole process.