Method for processing semiconductor substrate

Abstract

The processing method of the semiconductor substrate comprises the following steps: placing the semiconductor substrate and a graphite target in a vacuum chamber; hydrocarbon gas and polyurethane monomer gas are introduced into the vacuum chamber, the flow of the hydrocarbon gas is larger than that of the polyurethane monomer gas, a diamond-like carbon layer is formed on the surface of the semiconductor substrate, and polyurethane monomers are doped on the diamond-like carbon layer. The method is simple and easy to implement, low in cost and capable of forming the hole-sealable film layer on the surface of the semiconductor substrate, so that the rigidity of the diamond-like carbon layer is reduced, the flexibility of the diamond-like carbon layer is improved, brittle rupture of the diamond-like carbon layer is prevented, and the service life of the diamond-like carbon layer is prolonged.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor coating, and particularly to a method for processing a semiconductor substrate. Background Art

[0002] In the semiconductor field, diamond-like carbon (DLC) films have good hardness and certain corrosion resistance, and are commonly used as protective films formed on the surface of semiconductor substrates. However, DLC films have good rigidity but insufficient flexibility and are prone to brittle fracture. At the same time, with the development of semiconductor thinning, DLC films are getting thinner and some micropores appear on the surface. Corrosive media can easily enter the substrate through the micropores, thereby corroding the substrate and greatly reducing the performance of the film layer.

[0003] Therefore, there is an urgent need for an improved method for processing semiconductor substrates to overcome the above defects. Summary of the Invention

[0004] The purpose of the present invention is to provide an improved method for processing a semiconductor substrate. The method is simple and easy to implement, with low cost, and can form a pore-sealing film layer on the surface of the semiconductor substrate, thereby reducing the rigidity of the diamond-like carbon layer, improving its flexibility, preventing its brittle fracture, and thus extending its service life.

[0005] To achieve the above purpose, the method for processing a semiconductor substrate of the present invention includes the following steps:

[0006] Placing the semiconductor substrate and a graphite target in a vacuum chamber; and

[0007] Introducing a hydrocarbon gas and a polyurethane monomer gas into the vacuum chamber, where the flow rate of the hydrocarbon gas is greater than that of the polyurethane monomer gas, to form a diamond-like carbon layer on the surface of the semiconductor substrate and dope the diamond-like carbon layer with the polyurethane monomer.

[0008] Compared with the prior art, in the method for processing a semiconductor substrate of the present invention, a hydrocarbon gas and a polyurethane monomer gas are simultaneously introduced into the vacuum chamber to form a diamond-like carbon layer on the surface of the semiconductor substrate and dope the diamond-like carbon layer with the polyurethane monomer. Moreover, by controlling the flow rate of the hydrocarbon gas to be greater than that of the polyurethane monomer gas, the performance of the diamond-like carbon layer doped with the polyurethane monomer can be made more prominent. Specifically, the doped polyurethane monomer deposits a pore-sealing film layer on the surface of the diamond-like carbon layer, thereby reducing the rigidity of the diamond-like carbon layer to a certain extent, preventing its brittle fracture, improving its flexibility, preventing the film body from falling off, and thus extending the service life of the product.

[0009] Preferably, the flow rate of the hydrocarbon gas is 200 - 500 sccm, and the flow rate of the polyurethane monomer gas is 2 sccm - 3 sccm.

[0010] Preferably, the polyurethane monomer gas is obtained by adding polyurethane monomers, and the heating temperature is 130 - 180°C.

[0011] Preferably, the step of forming the diamond-like carbon layer includes: controlling the air pressure in the vacuum chamber to be 4×10 -2 to 4.5×10 -2 Pa, adjusting the bias voltage of the semiconductor substrate to be 40 - 50V, and setting the current of the graphite target to be 1.5 - 3.0A.

[0012] Preferably, the time for forming the diamond-like carbon layer is 20 - 25 minutes.

[0013] Preferably, the step of forming the diamond-like carbon layer further includes: controlling the rotation of the semiconductor substrate on the rotating rack, and the rotation speed is 30 - 60 rpm.

[0014] Preferably, the step of doping polyurethane monomers on the diamond-like carbon layer includes: adjusting the air pressure in the vacuum chamber to be 0.03 - 0.4 Pa, controlling the working voltage applied to the ion beam to be greater than 1000V, the working current to be 100 - 200 mA, and the pulsed bias voltage applied to the semiconductor substrate to be greater than 500V.

[0015] Preferably, the step of doping polyurethane monomers on the diamond-like carbon layer further includes: the doping time is 20 - 30 minutes, and more preferably, the doping thickness is 15 - 20 μm. Detailed Embodiments

[0016] To make the above objects, features, and advantages of the present application more obvious and understandable, the following describes the detailed embodiments of the present application in conjunction with some embodiments. Many specific details are set forth in the following description to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0017] In the description of the present application, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present application.

[0018] In addition, the terms "first" and "second" are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0019] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0020] The following further describes the method for processing a semiconductor substrate of the present invention in conjunction with embodiments, but does not limit the present invention thereby. The method of the present invention aims to provide a method for processing a semiconductor substrate, which is simple and easy to implement, has a low cost, can form a pore-sealing film layer on the surface of the semiconductor substrate, thereby reducing the rigidity of the diamond-like carbon layer on its surface, improving its flexibility, preventing it from cracking, and thus extending its service life.

[0021] In an embodiment of the method for processing a semiconductor substrate of the present invention, the following steps are included:

[0022] Placing the semiconductor substrate and a graphite target in a vacuum chamber; and

[0023] Introducing a hydrocarbon gas and a polyurethane monomer gas into the vacuum chamber, the flow rate of the hydrocarbon gas being greater than the flow rate of the polyurethane monomer gas, to form a diamond-like carbon layer on the surface of the semiconductor substrate and doping the diamond-like carbon layer with the polyurethane monomer.

[0024] In the method for processing a semiconductor substrate of the present invention, a hydrocarbon gas and a polyurethane monomer gas are simultaneously introduced into the vacuum chamber to form a diamond-like carbon layer on the surface of the semiconductor substrate and doping the diamond-like carbon layer with the polyurethane monomer. Moreover, by controlling the flow rate of the hydrocarbon gas to be greater than the flow rate of the polyurethane monomer gas, the obtained diamond-like carbon layer doped with the polyurethane monomer can have more prominent properties. Specifically, the doped polyurethane monomer deposits a pore-sealing film layer on the surface of the diamond-like carbon layer, thereby reducing the rigidity of the diamond-like carbon layer to a certain extent, preventing it from cracking, improving its flexibility, and preventing the film layer from peeling off, thus extending the service life of the product.

[0025] Specifically, in the present invention, polyurethane monomer gas can be obtained by heating polyurethane monomers, so as to prepare for subsequent doping. Specifically, first put the polyurethane monomers into a heating tank, raise the temperature to 130°C - 180°C to make them gaseous.

[0026] Next, prepare the working conditions of the vacuum chamber. First, place the semiconductor substrate and the graphite target at specific positions inside the vacuum chamber. The supply of hydrocarbon gas and the supply of polyurethane monomer gas are respectively connected to the vacuum chamber to provide working gases. When introducing the gases, control the flow rate of the hydrocarbon gas to be greater than that of the polyurethane monomer gas. In one embodiment, the flow rate of the hydrocarbon gas is 200 - 500 sccm, and the flow rate of the polyurethane monomer gas is 2 sccm - 3 sccm. For example, methane is used as the hydrocarbon gas, which is not limited herein.

[0027] Next, control the internal air pressure of the vacuum chamber to be 4×10 -2 to 4.5×10 -2 Pa, adjust the bias voltage of the semiconductor substrate to be 40V - 50V, and set the current of the high-purity graphite target to be 1.5A - 3.0A. Preferably, the semiconductor substrate rotates on a rotating rack at a rotation speed of 30 - 60 rpm. The process time can be controlled to be 20 - 25 minutes. Within a certain time of forming the diamond-like carbon layer, such as 10 minutes after the start, adjust the air pressure inside the vacuum chamber to be 0.03 - 0.4 Pa, control the working voltage applied to the ion beam to be greater than 1000V, the working current to be 100 - 200 mA, and the pulsed bias voltage applied to the semiconductor substrate to be greater than 500V. Thus, polyurethane monomers are doped on the diamond-like carbon layer, and the thickness of the doped layer is 15 - 20 μm. By such a method, a sealable film layer, that is, a polyurethane monomer layer, can be deposited on the surface of the diamond-like carbon layer, thereby reducing the rigidity of the diamond-like carbon layer, preventing it from cracking, improving its flexibility, preventing the film body from falling off, and thus extending the service life.

[0028] In summary, in the method for processing a semiconductor substrate of the present invention, hydrocarbon gas and polyurethane monomer gas are simultaneously introduced into the vacuum chamber, a diamond-like carbon layer is formed on the surface of the semiconductor substrate, and polyurethane monomers are doped on the diamond-like carbon layer. Moreover, by controlling the flow rate of the hydrocarbon gas to be greater than that of the polyurethane monomer gas, the performance of doping polyurethane monomers on the obtained diamond-like carbon layer can be more prominent. Specifically, the doped polyurethane monomers deposit a sealable film layer on the surface of the diamond-like carbon layer, thereby reducing the rigidity of the diamond-like carbon layer to a certain extent, preventing it from cracking, improving its flexibility, preventing the film body from falling off, and thus extending the service life of the product.

[0029] The above-disclosed are only the preferred embodiments of the present invention. Of course, the scope of rights of the present invention cannot be limited thereby. Therefore, equivalent changes made according to the scope of the patent application of the present invention still fall within the scope covered by the present invention.

Claims

1. A method for processing a semiconductor substrate, characterized in that, It includes the following steps: Place a semiconductor substrate and a graphite target in a vacuum chamber; And Introduce hydrocarbon gas and polyurethane monomer gas into the vacuum chamber. The flow rate of the hydrocarbon gas is greater than that of the polyurethane monomer gas, and a diamond-like carbon layer is formed on the surface of the semiconductor substrate and the polyurethane monomer is doped on the diamond-like carbon layer.

2. The method for processing a semiconductor substrate according to claim 1, wherein, The flow rate of the hydrocarbon gas is 200 - 500 sccm, and the flow rate of the polyurethane monomer gas is 2 sccm - 3 sccm.

3. The method for processing a semiconductor substrate according to claim 1, wherein, The polyurethane monomer gas is obtained by adding polyurethane monomer, and the heating temperature is 130 - 180 °C.

4. The method for processing a semiconductor substrate according to claim 1, wherein, The steps of forming the diamond-like carbon layer include: controlling the air pressure in the vacuum chamber to be 4×10 -2 to 4.5×10 -2 Pa, adjusting the bias voltage of the semiconductor substrate to be 40 - 50V, and setting the current of the graphite target to be 1.5 - 3.0A.

5. The method for processing a semiconductor substrate according to claim 4, wherein, The time for forming the diamond-like carbon layer is 20 - 25 minutes.

6. The method for processing a semiconductor substrate according to claim 4, characterized in that, The step of forming the diamond-like carbon layer further includes: controlling the rotation of the semiconductor substrate on a rotating rack, and the rotation speed is 30 - 60 rpm.

7. The method for processing a semiconductor substrate according to claim 1, wherein, The step of doping the polyurethane monomer on the diamond-like carbon layer includes: adjusting the air pressure in the vacuum chamber to 0.03 - 0.4 Pa, controlling the working voltage applied to the ion beam to be greater than 1000 V, the working current to be 100 - 200 mA, and the pulsed bias voltage applied to the semiconductor substrate to be greater than 500 V.

8. The method for processing a semiconductor substrate according to claim 7, wherein, The step of doping the polyurethane monomer on the diamond-like carbon layer further includes: the doping time is 20 - 30 minutes.

9. The method for processing a semiconductor substrate according to claim 8, wherein, The doping thickness is 15 - 20 μm.