TW297944B - - Google Patents

Description

Central Standards Bureau M3 of the Ministry of Economic Affairs: Industrial-Consumer Cooperation Du Printed Α7 Β7 V. Description of the Invention (1) Background of the Invention 1. Field of the Invention The present invention relates to a method of manufacturing a field oxide layer to make a device electrically connected to other devices Insulation, and more particularly related to the process of using nh3 gas heat treatment to increase the active area. 2. Description of the prior art Generally speaking, the field oxide layer of the electrical insulation device is made by the LOCOS (localized silicon oxidation reaction) method, which uses an oxidation shielding layer such as a nitride layer to oxidize a part of the silicon substrate Area. However, because the LOCOS method forms a beak-shaped crossbow that reduces the active area of the device, improved LOCOS methods such as OSELO (compensated LOCOS) and MOSELO (modified OSELO) methods are currently in practical use. The OSELO method forms a trench in the silicon substrate before oxidation. That is, before the silicon substrate is oxidized to form a field oxide layer (where the pad oxide layer and the oxidation shielding layer (nitride) are patterned first, so that the device isolation area of the silicon substrate is exposed), a nitride spacer layer A trench is formed on the sidewall of the oxidation masking layer and a trench is fabricated by etching the silicon substrate to a thickness of about 300 to 700A. This nitride spacer prevents the oxidation of the silicon substrate from the interface between the pad oxide layer and the silicon substrate. However, the wider the width of the nitride spacer, the narrower the oxidized area. This is to use the nitride spacer described above to destroy the insulation effect. On the other hand, the problem with the OSEL0 method is that the extremely narrow width of the nitride spacer layer will increase the beak-shaped crossbow. The size of this paper is applicable to the Chinese National Standard (CNS) A4 specification (210X297mm) ^-install ------------ ^ I line (Read the precautions on the back before filling this page) Economy Printed by the Ministry of Central Standards Bureau Employee Consumer Cooperative A7 ------------ B7_ V. Description of the invention (2) Summary of the invention The present invention (the purpose is to provide a bird ’s beak-shaped crossbow and increase the field Method for insulating effect of oxide layer. According to an aspect of the present invention, a method for manufacturing a field oxide layer i in a semiconductor device is provided herein, which includes the following steps: providing a silicon substrate; forming an oxide layer on the silicon substrate; and In a nitrogen-containing atmosphere, when performing a heat treatment process on the silicon substrate, nitrogen is injected into the oxide layer to avoid the diffusion of oxygen along the interface between the silicon substrate and the oxide layer. _ According to another aspect of the invention The method for manufacturing a field oxide layer in a semiconductor device includes the following steps: providing a silicon substrate; forming an oxide layer on the silicon substrate; and forming the silicon substrate in an atmosphere containing nitrogen gas When the heat treatment process is performed on the material, nitrogen is injected into the oxide layer In order to avoid the diffusion of oxygen along the interface between the broken substrate and the oxide layer, a nitride layer is formed on the oxide layer; the nitride layer and the oxide layer are patterned to make the field region of the broken substrate Exposure; forming a nitride spacer on the sidewalls of the nitride layer and the oxide layer, and forming a trench by etching the silicon substrate; and performing a thermal oxidation process on the exposed silicon substrate. Brief description of other objects and aspects of the present invention will become easier to understand from the description of the following specific examples and reference to the accompanying drawings, in which: FIGS. The detailed description of the preferred specific examples is described in this document. The present invention will be described in detail below with reference to Figures 1A to 1E. This paper scale is applicable to the Chinese National Standard (CNS) Α4 specification (210X297 mm) (please Read the precautions on the back and then fill out this page)-installed., * Τ line 297944 Printed by the Ministry of Economic Affairs Central Standards Bureau Negative Consumers Cooperative Fifth, the description of invention (3). First, as shown in 1A, a silicon-based Timber 1 upper part Oxidation, and then the protective oxide layer 2 is formed on the base material 1 and has a thickness of about 50 to 500 A. The crushed substrate 1 with the protective oxide layer 2 is made of nitrogen-containing gas (for example, Including njj3, N〇2 gas) and a N2 gas heat treatment for 30 to 120 minutes ^ n2 gas is used to stabilize the device. At this time, the concentration of NH3 or N02 gas in all gases exceeds 50% _ and the device is It is heat-treated at a concentration of 800 to 1100 ec and a pressure of 10 to 100 torr. As a result, a small amount of nitrogen atoms exist near the interface between the silicon substrate 1 and the pad oxide layer 2 "Number 3 represents an oxide layer containing nitrogen atoms." Next, as shown in FIG. 1B, a nitride layer 4 is formed on the pad oxide layer 2 with a thickness of about 1000 to 2000 A to prevent the silicon substrate i from It is oxidized during the heat treatment process. Part of the nitride layer 4 and the protective oxide layer 2 (including the third layer) are removed and removed using a photomask defining the field area, thus exposing part of the silicon substrate 1. As shown in FIG. 1C, in order to form a nitride spacer layer 5 on the side walls of the nitride layer 4 and the pad oxide layer 21, the obtained nitride layer structure is deposited with a thickness of about 100 to 500 A and using anisotropy The etching process is to etch β. In addition, when etching the nitride layer, the over-etching process is controlled to etch the silicon substrate 1 to form a trench to a depth of about 200 to 700 Å. As shown in FIG. 1D, the exposed silicon substrate is oxidized at a high temperature by a thermal oxidation process and the field oxide layer 6 is formed to have a thickness of about 2500 to 3500a. Because the gas atoms in the protective oxide layer prevent oxygen from diffusing along the interface between the broken substrate and the pad oxide layer, the bird's beak-like curvature is kept to a minimum. (Jing first read the precautions on the back and then fill out this page) • Packing. The paper size of the binding book is applicable to the Chinese National Standard (CNS) A7 B7 5. Invention description (4) Finally, as shown in Figure 1E, remove the nitrogen After the chemical compound layer 4, the nitride spacer layer 5 and the pad oxide layer 2. After a wet etching process, a sacrificial oxidation process is implemented on the surface of the silicon substrate. This damage oxidation process removes the damaged portion of the silicon substrate 1 by forming a thermal oxide layer on the surface of the broken substrate 1 with the damaged portion and by removing the thermal oxide layer. As described above, it is obvious that the present invention is effective for increasing the active area by preventing bird-like bending from occurring at the interface between the silicon substrate and the pad oxide layer. In addition, the present invention can form a thick field oxide layer β having an excellent insulating effect because a thin nitride layer can be used. Therefore, the present invention can be applied to different LOCOS methods. Although the preferred specific examples of the present invention have been disclosed to illustrate the use, those skilled in the art will recognize various modifications, additions and substitutions are possible, and they should not be far from the invention within the scope of the attached patent application Reveal the appearance and spirit. Binding — Threading (Please read the precautions on the back before filling in this page) Printed by the Employees ’Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs This paper is the standard Ningguo National Mound Standard (CNS) A4 specification (210X297mm

Claims (1)

Scope of patent application A8 B8 C8 D8 Printed by the Employee Consumer Cooperative of the Central Bureau of Economics of the Ministry of Economy ι · A method for manufacturing field oxide layers in semiconductor devices, which includes the following steps: providing a silicon substrate; forming an oxide on the dream substrate Layer; and in an atmosphere of nitrogen-containing gas, by applying a heat treatment process to the silicon substrate, nitrogen is injected into the oxide layer to avoid oxygen diffusion along the interface between the silicon substrate and the oxide layer. 2. The method according to item i of the patent application scope, wherein the nitrogen-containing gas is NH3 or ^ 02 gas. 3. According to the method of item 1 of the patent application scope, the temperature is about 800 to 1100. (: Implemented below. 4. The method according to the first item of the patent application scope is carried out for 30 to 120 minutes. 5. The method according to the second item of the patent application scope includes N2 gas snake. 6. According to the item 5 of the patent application garden The method is more than about 50%. 7- According to the method of the patent application, the pressure of the method is about 10 to 100 Torr. 8 According to the patent application, the method of the first item is about 50 to 500A. 9. A kind of semiconductor A method for manufacturing a field oxide layer in an apparatus, which includes the following steps: providing a crushed substrate; wherein the heat treatment process is wherein the heat treatment process is performed by the heat treatment process and wherein the concentration of the nitrogen-containing gas is used wherein the heat treatment process is the oxide layer formed therein (Please read the precautions on the back before filling in this page)-Installation. Threading-8-A8 B8 C8 D8 printed by the Employee Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs 6. Scope of patent application ---- on the silicon substrate An oxide layer is formed; in an atmosphere containing nitrogen skulls, the burial machine, and the brothers "Hunting You apply a heat treatment process to the silicon substrate of the child, and inject nitrogen into the oxide layer. To prevent oxygen from diffusing along the interface between the silicon substrate and the oxide layer; forming a nitride layer on the oxide layer; patterning the oxidant layer and the oxide layer to expose the field area of the silicon substrate Forming a nitride spacer on the sidewalls of the nitride layer and the oxide layer, and forming a trench by etching the silicon substrate; and applying a thermal oxidation treatment process to the exposed broken substrate. 10. According to the application The method of item 9 of the patent scope, wherein the thickness of the groove formed is ^ 200 to 700A. 11. According to the method of item 9 of the patent application, the nitrogen-containing gas is Nh3 or no2 gas. 12. According to the scope of the patent application The method of item 9, wherein the heat treatment procedure is carried out at a temperature of about 800 to 1100 ° C. 13. According to the method of item 9 of the patent application, the heat treatment procedure is carried out for 30 to 120 minutes. 14. According to the patent application The method of item 11 of the scope, wherein the heat treatment process additionally contains N2 gas. 15. According to the method of item 9 of the patent application, the concentration of the nitrogen-containing gas exceeds 50% »16. According to the patent application The method of item 9, in which the heat treatment process is carried out under a pressure of about 10 to 100 Torr. -9- This paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297mm) ΙΓΙ installation! (Please read the notes on the back first Please fill in this page again) -Line A8 B8 C8 D8 Printed by Employee Consumer Cooperative of Central Bureau of Standards of the Ministry of Economic Affairs 々, patent application scope 17. According to the method of item 9 of the patent application scope, the thickness of the oxide layer formed is about 50 Up to 500A. (Please read the precautions on the back before filling in this page). Binding. Binding -10- This paper size is applicable to China National Standard (CNS) A4 specification (210X297mm)