TW200419671A - Method for polymer removal after an etching process - Google Patents

Abstract

A method of manufacturing a semiconductor device that includes providing a wafer substrate, providing an insulator over the wafer substrate; depositing a first layer over the insulator, forming a layer of dielectric material over the first silicon layer, depositing a second silicon layer over the layer of dielectric material, providing a photoresist layer over the second silicon layer, patterning and defining the photoresist layer, etching the second silicon layer, the layer of dielectric material, the first silicon layer and the insulator unmasked by the photoresist, removing the photoresist layer, and cleaning at least the etched first silicon layer with a mixture of deionized water and ozone gas.

Description

200419671

The present invention relates to a method for manufacturing a semiconductor device, and more particularly, to a method for removing a polymer after an etching process. Prior art memory devices generally include a first gate formed on a first dielectric layer, and the first dielectric layer is formed on a semiconductor substrate. In terms of flash memory (flash memory), the first gate is a floating ing gate, and the first dielectric layer is a tunneling oxide ^. A flash memory device further includes a control gate formed on the floating gate and a second dielectric layer between the control gate of the floating gate and the control gate. /, In the memory device manufacturing process, the gate is made by deposition, patterning, and etching. However, the etching process often results in the formation of undesired polymeric materials along the gate sidewalls being etched. These polymeric materials will cause some of these disadvantages, such as random single bit data retention failure. In traditional semiconductor processes, a β / 糸 step is usually required after the etching process. One of the traditional cleaning steps is the RCA cleaning method developed by ψ e r n e r κ e Γ n. This RCA cleaning is a two-step process, which includes Standard Clean 1 (also known as SC-1) and Standard Clean 2 (also known as SC-2). In standard cleaning 1, the SC-1 solution is usually ammoni um hydroxide, hydrogen peroxide, and hydrogen peroxide, which are mixed between 1: 1: 5 to 1: 2 ·· 7, and Deionized water. Standard cleaning 2

10312twf.ptd Page 6 200419671 V. Description of the invention (2) A hydrogen-containing acid (117 (11′〇 (: 111〇1 ^ 〇 & (^ (1), hydrogen peroxide, and deionized water compounds ( compos iti on). Except for RCA etching, other traditional cleaning solutions use a mixture containing sulfuric acid (su 1 furicacid) and hydrogen peroxide to remove organometallic impurities. However, although these conventional solutions can Effectively remove various contaminants, but these solutions will also etch the tunneling oxide layer and reduce the integrity of the tunneling oxide layer. This undesired degradation with the tunneling oxide layer will damage the reliability of the memory device (ReliabiHty) and long-term performance. The inventor therefore proposes a method of manufacturing a semiconductor device to provide a wafer substrate. Then, an insulator is provided on the wafer substrate, and then A first silicon layer is deposited on the insulator. Then, a dielectric material layer is formed on the first silicon layer, and then a dielectric and a second stone layer are formed. Then, the second stone A photoresist is provided on the layer; ㈡: 32 layer, which etches the second stone layer that is not covered by the photoresist layer, " electrical material layer, 帛 -hard layer and insulator. Then the photoresist layer is referred to as two = The mixture of sub-water and ozone gas (.zone gas) is at least clean. The present invention also proposes a dielectric material layer for manufacturing semiconductor elements, and then depositing a silicon layer on the dielectric material layer to provide a photoresist layer. Re-patterning and defining the silicon layer and the dielectric material layer that are not covered by the photoresist layer. The method includes providing a silicon layer. Next, the resist layer. Then, the photoresist layer is removed after etching.

200419671 V. Description of the invention (3) Divide it with deionized water and odor bombardment ^ The present invention also proposes a method for preparing 2 halves: 2 compounds for cleaning. -Wafer substrate. Then, Yu Jing's method includes providing a silicon layer on the edge body. After that, it is provided on the silicon edge body, and then is provided on the dielectric material layer_light / formation-dielectric material layer, layer. Then, the photoresist is not patterned and the photoresist layer is removed to remove ions; the insulator. The layer is then removed. / The mixture of six lice rolls cleans other additional features of the invention and To a certain extent, it can be mentioned in the following content, the features and advantages of the present invention. And, through the ^ ^ 2 embodiment, the content of the patent application obtained and learned through the ^ ^ sister in addition to the scope of the patent application The former Ye Shi ^ the characteristics and advantages of the present invention. The outline of f ^ # X 明 and subsequent preferred embodiments are used for explanation and not to limit the present invention. 2 Let the above of the present invention And other features and advantages can be more clearly described below with reference to preferred embodiments, and in conjunction with the accompanying drawings < for detailed implementation. 4 Reference will be made to the preferred embodiments of the present invention detailed below, and In the attached drawings, anyway, as long as it is a number in the diagram, it represents the same component. Method t invention proposes a method for removing the polymer formed on the gate surface. Figures 1-3 are according to one of the present invention. Manufacturing steps of the preferred embodiment Sectional view. Please refer to FIG. 1. The preferred embodiment of the present invention first defines a 200419671. V. Description of the Invention (4) Insulating wafer substrate 10. Then an insulator 2 is formed on the wafer substrate 10. 20 may be composed of an oxide or a tunneling oxide. Subsequently, a step of cleaning the surface of the insulating layer 20 is performed to remove unwanted contaminants. Then, the insulator is applied to the insulator. A first gate layer 30 is provided on 20, such as polycrystalline silicon. The first gate layer 30 may be deposited on the insulator using a conventional process such as a chemical vapor deposition process (chemica vapor deposition, abbreviated as CVD). Thereafter, a dielectric material layer 40 is provided on the first gate layer 30. In one embodiment, a photoresistive sound layer is not deposited on the dielectric material layer 40): then • 'Using a After the traditional lithography process is patterned and determined, the patterned and defined photoresist layer is used as a military curtain, and a dry etching is performed to form a semiconductor structure including an insulator 20 and a first semiconductor. However, the presence of several organic compounds in the dry button layer 30 can be due to by-products (b " roduct) in the gas. Next,:; 3 :: wall :: expected a cleaning step 1 to remove unexpected and unwanted production: specifically performed These by-products can be processed through the following oxidation process. Moreover, 〇3 + CxHy—〇2 + CzHa (〇H) b or the present invention makes m: c "2〇 + cA〇 ⑷xtrue) Λ except two substances and ozone (DI, ^ Fang Wei Tian 丨" house, the spleen

The structure is immersed in the ozone-removing soil bottom 10 and the structure formed thereon to remove by-products and water. Therefore, the present invention also requires a good cleaning process. Brother 2 'can be provided on the dielectric material layer 40_

200419671 V. Description of the invention (5) A gate 50: After that, a photoresist layer 60 is provided on the second gate layer 50. ^ ^ μ, Z, according to Fig. 3, ‘Utilization—Traditional lithography process patterning ΐI, and 且 60. After that, the patterned and defined photoresist layer 60 is used as a dry etching to form an insulator 20, a first gate layer 30, a dielectric material layer 40, and a second gate layer 50. Of several semiconductor structures. Each semiconductor structure represents a memory cell. In this embodiment, the first gate layer 30 is a floating gate, the second gate layer 50 is a control gate, and the insulator 20 is a tunnel oxidation. Layer (tunneHng oxide). Various gases used in the etching process include carbofluoride or carbon chloride organic compounds. Therefore, during the dry etching, an unwanted by-product 70 'such as a polymer (poiymer) is formed along the side wall of the floating gate 30, the control gate 50, or both. Then, the photoresist layer 60 is peeled and removed. This is followed by a special cleaning step to remove unwanted by-products 70. Moreover, the polymer 70 can be removed through the following oxidation process: 03 + CxHy —02 + CzHa (0H) b or 03 + CxHy-> C02 + H20 + CaHb0 In one embodiment, deionized water and ozone ( DI -03) to remove polymer 70, and it immerses substrate 10 and the structure formed on it into deionized water containing ozone gas. Therefore, the method of the present invention can remove the macromolecules 70 to obtain a cleaning procedure superior to the conventional cleaning process. Figure 4 shows the removal of the polymer using a conventional standard SC-2 cleaning process and a cleaning method according to the preferred embodiment 4 of the present invention.

10312twf.ptd Page 10 200419671 V. Description of the invention (6) Comparison chart of capabi 1 ity). The polymer removal capability is based on the values of three parameters: the number of defects (defec1: count), the density of defects (defec1: density), and the total number of depressions (am0⑽ of total pi ts). The higher of these three parameters indicates that it has a higher level of defect. Please refer to FIG. 4. The DI-〇3 treatment of the present invention shows better performance at different temperatures than the cleaning treatment using the conventional Sc-2 solution.

Polymer removal capability. In addition, if the present invention is selectively combined with a H-transmission process such as SC-1 and SC-2 treatment, the cleaning effectiveness should also be improved. After that, conventional semiconductor components and other semiconductor structures can be continued. Λ 疋 成 —Although the present invention has been disclosed in the preferred embodiment as described above, the present invention is limited in its own right. Anyone skilled in this art can: within the scope of the invention and various modifications and turbid decorations 2; The scope of this patent is limited by the scope of the attached patent application.

200419671 Schematic illustrations Figures 1 to 3 are cross-sectional views of manufacturing steps according to a preferred embodiment of the present invention; and Figure 4 is a standard SC-2 cleaning process and according to the preferred embodiment of the present invention Comparison curve of polymer removal ability of cleaning methods. Graphical description 10 · Wafer substrate 20: Insulator 30 ^ 50: Gate layer 40: Dielectric material layer 60: Photoresist layer 70 •• By-products

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Claims (1)

200419671 6. Application Patent Scope 1. A method for manufacturing a semiconductor device, comprising: providing a wafer substrate; providing an insulator on the wafer substrate; depositing a first silicon layer on the insulator; and on the first stone Forming a dielectric material layer on the layer; depositing a second silicon layer on the dielectric material layer; providing a photoresist layer on the second silicon layer; patterning and defining the photoresist lip; etching is not performed by the light The second silicon layer, the dielectric material layer, the first silicon layer and the insulator covered by the resist layer; removing the photoresist layer; and cleaning at least the first silicon layer with a mixture of deionized water and ozone gas. 2. The method as described in item 1 of the patent application scope, wherein the insulator comprises an oxide. 3. The method described in item 1 of the scope of patent application, further comprising cleaning the etched second silicon layer. 4. The method according to item 1 of the scope of patent application, wherein the step of etching the second stone layer, the dielectric material layer, the first stone layer and the insulator not covered by the photoresist layer includes a dry method Etching. 5. The method according to item 1 of the scope of patent application, wherein the step of cleaning at least the first silicon layer with a mixture of deionized water and ozone gas further includes cleaning with a standard cleaning solution. 6. The method according to item 1 of the patent application, wherein 10312twf.ptd Page 13 200419671 VI. Scope of patent application The step of cleaning at least the first silicon layer by a mixture of water and ozone gas further includes cleaning with a standard cleaning 2 solution. 7. A method for manufacturing a semiconductor device, comprising: providing a dielectric material layer; depositing a silicon layer on the dielectric material layer; providing a photoresist layer on the silicon layer; patterning and defining the photoresist layer ; Etching the silicon layer and the dielectric material layer not covered by the photoresist layer I: removing the photoresist layer; and cleaning with a mixture of deionized water and ozone gas. 8. The method as described in claim 7 of the scope of the patent application, wherein the silicon layer comprises polycrystalline silicon. 9. The method as described in claim 7 of the scope of the patent application, wherein the silicon layer includes a floating gate. I 0. The method as described in item 7 of the scope of the patent application, wherein the silicon layer includes a control gate. II. The method according to item 7 of the scope of patent application, wherein the step of cleaning with a mixture of deionized water and ozone gas further includes cleaning with a standard cleaning 1 solution. 1 2. The method according to item 7 of the scope of patent application, wherein the step of cleaning with a mixture of deionized water and ozone gas further includes cleaning with a standard cleaning 2 solution. 13. A method for manufacturing a semiconductor device, including: a wafer substrate, 10312twf.ptd Page 14 200419671 Sixth, the scope of the patent application is to provide an insulator on the wafer substrate; deposit a silicon layer on the insulator; form a dielectric material layer on the silicon layer; on the dielectric material layer Providing a photoresist layer; patterning and defining the photoresist layer; etching the silicon layer and the insulator not covered by the photoresist layer; removing the photoresist layer; and cleaning and etching with a mixture of deionized water and ozone gas The silicon layer. 10312twf.ptd Page 15