TW410380B - Method of forming the gate oxide - Google Patents

Abstract

This invention provides a method of forming the gate oxide and is appropriate for use on the substrate that has the defined active region. A thermal oxide layer is formed on the active region of the semiconductor substrate from the use of thermal oxidation method. A hydrogen annealing process is then conducted onto this thermal oxide layer at a temperature between 600 DEG C and 1100 DEG C. The following nitrogen and/or argon annealing process is conducted onto the thermal oxide layer mentioned above so as to form the gate oxide layer.

Description

410380 Five 'Explanation of invention (1)

The present invention relates to a semiconductor device manufacturing process, and more particularly, to a method for forming a gate oxide layer of a high-quality metal-oxide semiconductor transistor (MOS transistor).

The gate oxide layer is usually an oxide layer (such as the Si 02 layer) located below the gate electrode of the metal-oxide semiconductor transistor. The transistor passes through this gate oxide layer to induce the channel's electric charge ', so it must be an oxide layer of excellent quality. Therefore, it is usually in a high-purity dry oxidizing environment, and the temperature is between 85 and 1100. (: Temperature is used to dry oxidize Si wafer) to form a gate oxide layer with a thickness of 30 ~ 150 angstroms. A method for improving the gate oxide layer has been proposed, such as silicon crystal After thermal oxidation and dry oxidation, the silicon wafer on which the thermal oxidation layer is formed is subjected to an annealing process such as nitrogen (') or inert gas such as argon (Ar). To improve the integrity of the gate oxide (gate oxj, integrity; G0I). Generally, parameters such as breakdown voltage (Vbd) and breakdown capacitance (Qvd) are used as indicators of the quality of the gate oxide. However, with integrated circuits Design rule continues

L Ϊ Drum: It is necessary to provide a thermal oxide layer with better electrical characteristics, ie, good gate oxide layer integrity. The purpose of the present invention is to provide a kind of gate oxide to ensure the integrity of the 2 liter gate oxide layer, and thus to ensure the reliability of the solar cow body. Method:-A method for forming a gate oxide layer. I have an active & semiconductor substrate. The above method includes

410380 ^ _ V. Description of the invention (2) '--- The following steps (1) use a thermal oxidation method to form a thermal oxide layer on the active area of the semiconductor substrate; and apply hydrogen tempering to the thermal oxide layer (1). Scales to form a gate gasification layer. Furthermore, the temperature of the above-mentioned radon gas tempering step is 600-110 ° C, and radon is preferably 600-800 ° C. Furthermore, after or before the hydrogen tempering step, the thermal oxidation layer is further included. Tempering step of inert gas such as nitrogen and / or argon. The temperature of the above-mentioned inert gas tempering treatment is between 600 and 110 (the RC is further described above) The thermal oxidation method is in an environment containing dry oxygen The following is a brief description of the drawings. FIGS. 1 to 3 are cross-sectional views showing a process for forming a gate oxide layer of a metal-oxide semiconductor transistor according to a preferred embodiment of the present invention. Explanation of symbols 100 to semiconductor substrate (single-crystal silicon substrate) ). FOX ~ field oxide layer. AA ~ active area. 102 ~ thermal oxide layer. 102a ~ gate oxide layer. Example 〆 The following is a cross-sectional view of the process of forming the gate oxide layer using FIG. 3 to explain in detail A preferred embodiment of the present invention.

First, "please refer to Fig. 1". Fig. 1 shows that a field halide FOX is formed.

The cross section of the semiconductor substrate 100 'the above-mentioned field oxide FOX is formed at a high temperature using a wet oxidation method, which is used to define an active region. A A. The semiconductor substrate 100 is, for example, a single crystal silicon substrate.

Next, referring to FIG. 2, an oxidation process is performed at a temperature of 850 to 1100 X: in an environment containing dry oxygen to form a thermal oxide layer 102. Then, the hydrogen (Ha) tempering treatment step is performed at a temperature of 600 to 600 ° C for 20 to 40 seconds, and the temperature of the hydrogen tempering step is preferably 600 to 800 ° C. Finally, D 'Please refer to FIG. 3, and perform a tempering treatment step of an inert gas such as nitrogen (Na) and / or argon (j \ r) at a temperature of 600 to 11000 ° C to form a current Used as the gate oxide layer 〇2a after tempering thermal oxidation layer. Subsequent steps of the polycrystalline silicon layer, the insulating layer deposition, the lithography, the etching, and the ion implantation are performed in accordance with the conventional technology to complete the fabrication of the metal-oxide semiconductor device. The tempering treatment in the above embodiment is performed with hydrogen and then with nitrogen and / or argon, but the present invention is not limited thereto. The purpose of the present invention can be achieved by replacing the hydrogen tempering treatment and the nitrogen and / or argon tempering treatment. ~ Features and effects of the present invention

The invention is characterized in that after the thermal oxidation layer used as the gate oxide layer 102 is formed by a dry oxidation method, a hydrogen tempering treatment step is added, and then an inert gas tempering treatment is performed. Thereby, the quality of the gate oxide layer can be further improved, and the reliability of the gold-oxygen semi-transistor can be ensured. Although the present invention has been disclosed above in the preferred embodiment, it is not intended to

Page 6_410380_ V. Description of the invention (4) The invention is limited. Any person skilled in the art can make changes and retouches without departing from the spirit and scope of the invention. Therefore, the scope of protection of the invention should be considered after The attached application patent shall prevail.

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Claims (1)

410360 6. Scope of Patent Application 1. Kinds of gate oxidation / seed formation…, used for semiconductor substrates in the field, the above method includes the following steps: using a thermal oxidation method to form an active thermal oxidation layer on the semiconductor substrate; and pairing the above The thermally quenched layer is subjected to a hydrogen tempering step to form a gate oxygen interlayer. 2. The method for forming a gate oxide layer as described in item 1 of the scope of the patent application, wherein the semiconductor substrate is a single crystal silicon substrate β 3 The method for forming a gate oxide layer as described in item 1 of the scope of the patent application, wherein the temperature of the above-mentioned hydrogen tempering step is 600 to it 6 4. The gate oxide formation as described in the third item of the scope of patent application Layer method 'wherein the temperature of the above-mentioned hydrogen tempering step is 600 ~ 800 ° C. 5. The method for forming a gate oxide layer according to item 3 of the scope of the patent application, wherein the time of the hydrogen tempering step is 20 seconds to 40 seconds. 6. The method for forming a gate oxide layer as described in item 1 of the scope of patent application, wherein after performing the hydrogen tempering step, the method further includes performing an inert gas tempering step on the thermal oxide layer. 7. The method for forming a gate oxide layer according to item 6 of the scope of the patent application, wherein the inert gas is tempered with nitrogen and / or argon as a reaction gas. 8. The method for forming a gate oxide layer as described in item 4 of the scope of patent application, wherein the temperature of the above-mentioned inert gas tempering zone is between 600 and 1100 ° C. 9. The method for forming a gate oxide layer as described in item 1 of the scope of patent application Scope of patent application 6 :, scope of patent application __ /, before performing the hydrogen tempering step, the inert gas tempering step further includes the thermal oxidation method above, and 2 in the patent scope of the 9th ... The method for forming a closed-electrode layer is an anti-i gas tempering step. The step is to use a nitrogen and / or bombardment method. ”The method for forming a gate oxide layer as described in item 1 of the scope of the patent application” /, The above-mentioned thermal oxidation method is performed in an environment containing dry oxygen. 12. —A method for forming a gate oxide layer, which is suitable for a localized semiconductor substrate. The above method includes the following steps: The thermal oxidation method is used to form a thermal oxide layer in the active region of the semiconductor substrate; at 600 ° C ~ lioot At the temperature of:, the thermal oxidation layer is subjected to a hydrogen tempering step; and the thermal oxidation layer is subjected to a nitrogen and / or argon tempering treatment to form a gate oxide layer. 1 3. The method for forming a gate oxide layer according to item 2 of the patent application scope, wherein the semiconductor substrate is a single crystal silicon substrate. 1 4. The method for forming a gate oxide layer according to item 12 of the scope of the patent application, wherein the temperature of the hydrogen tempering step is 600 to 800 ° C. 15. The method for forming a gate oxide layer as described in item 12 of the scope of the patent application, wherein the temperature of the above-mentioned nitrogen and / or argon tempering treatment is between 60 ° and 1100 ° C. 16 · The method for forming a gate oxide layer as described in item 12 of the scope of patent application, wherein the above-mentioned thermal oxidation method is performed in an environment containing dry oxygen. Page 9 ^ IQcQO Page 10