etchant

An etching solution and etching technology, applied in the direction of surface etching composition, chemical instruments and methods, electrical components, etc., can solve the problems of effective utilization of resources, influence of etching rate, etc., and achieve small composition changes and low exchange frequency Effect

Active Publication Date: 2016-03-02
DAIKIN IND LTD
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0012] In addition, in the semiconductor manufacturing process, it is known that the wafer is usually etched by immersing it in a chemical solution tank containing buffered hydrofluoric acid. The pure water cleaning tank is brought into the chemical solution tank, and the components of the chemical solution are diluted, so that the composition of the chemical solution changes with time, which has a significant impact on the etching rate
Therefore, the entire chemical solution has to be exchanged over time, and there are problems in terms of processing efficiency and effective use of resources.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • etchant
  • etchant
  • etchant

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1～3 and comparative example 1

[0072] Examples 1-3 and Comparative Example 1: Evaporation Test

[0073] 50% by mass of hydrofluoric acid (A), 40% by mass of ammonium fluoride (B) (containing 0.07% by mass of HF), and salts (C) obtained from the acids and salts shown in Table 1 were mixed at predetermined concentrations and water (D) to prepare 400g of etching solution. The HF concentration was adjusted by supplementing the deficiency of the amount of hydrofluoric acid contained in the added ammonium fluoride (B) with 50% by mass of hydrofluoric acid (A). In addition, among the acids and bases used in the preparation of the salt (C), 100% by mass of acetic acid, CH 3 CH 2 NH 2 Use 70% by mass aqueous solution, (CH 3 ) 3 A 25% by mass aqueous solution was used for NOH.

[0074] [Weight measurement of etching solution]

[0075] Store half of the prepared etching solution in an airtight container. The remaining half was put into a cylindrical container with a diameter of 8 cm, and the weight (initial ...

Embodiment 4～5

[0088] Embodiment 4~5 and reference example 1: Evaporation test

[0089] NH in the etchant 4 The concentration of F was adjusted to 2% by mass, and the NH 4 Examples 4 to 5 and a reference example were prepared in the same manner as in Examples 1 to 3 and Comparative Example 1 except that the concentration of F, the type of salt (C), and the amount of salt (C) added were adjusted as shown in Table 3. 1 etchant. Among them, acetic acid and CH 3 CH 2 NH 2 The same thing as Examples 1-3 and Comparative Example 1 was used, and the 44 mass % aqueous solution was used for choline.

[0090] Table 3 shows the compositions of Examples 4 to 5 and Reference Example 1, and Table 4 shows the results.

[0091] [table 3]

[0092]

[0093] [Table 4]

[0094]

[0095] Even in the NH 4 When the concentration of F is adjusted to 2% by mass, by adding salts obtained from acetic acid and tetramethylammonium hydroxide, and salts obtained from acetic acid and choline, the etching ra...

Embodiment 6～7 and comparative example 2

[0096] Examples 6-7 and Comparative Example 2: Water dilution test

[0097] 1000 g of each chemical solution was prepared by the same chemical solution preparation method as shown in the chemical solution evaporation test, and 200 g of the chemical solution was prepared by mixing the predetermined amount shown in Table 5 with water, and the etching rate at 25° C. was measured.

[0098] [Measuring method of etching rate]

[0099] Adjust the temperature of the etching solution stored in an airtight container to 25°C, and dip a 1.5cm×1.2cm thermally oxidized film (thin film) in each chemical solution for 5 minutes after measuring the initial film thickness, and then wash it off with water The chemical solution was dried with nitrogen gas, and then the film thickness of each diaphragm was measured. Then, the difference in film thickness before and after immersion was used as the etching amount, and the etching amount was divided by the etching time as the etching rate.

[0100...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The present invention provides a kind of etchant, it contains hydrofluoric acid (A), ammonium fluoride (B), by the acid (C1) that has higher pKa than hydrofluoric acid (pKa=3.17) and has higher than ammonia ( The salt (C) and water (D) obtained from the base (C2) of pKa (pKa=9.24) have little change in composition due to the evaporation of the chemical solution, and the exchange frequency of the chemical solution is low, and can be uniform even over a long period of time. to etch the silicon oxide film.

Description

technical field [0001] The present invention relates to an etchant for a silicon oxide film used in semiconductor engineering, liquid crystal engineering, etc., a method for producing the same, an etching method using the etchant, and a method for producing an etched product using the etchant. Background technique [0002] A wet etching solution for a silicon oxide film uses a mixed solution of hydrofluoric acid and ammonium fluoride solution to buffer hydrofluoric acid (for example, Patent Document 1). In the semiconductor manufacturing process, it is known that the wafer is etched by immersing it in a chemical solution tank containing buffered hydrofluoric acid. However, since the chemical solution tank usually has an opening for immersing the wafer, the evaporation of the components of the chemical solution causes the chemical solution to be etched. Composition changes over time, with a significant impact on etch rate. Therefore, the entire chemical solution has to be ex...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): H01L21/306H01L21/308
CPCC09K13/08H01L21/31111H01L21/306H01L21/308
Inventor 板野充司中村新吾毛塚健彦江藤友亮
Owner DAIKIN IND LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap