DE-112010003895-B4 - Method for producing a fine metal structure

DE112010003895B4DE 112010003895 B4DE112010003895 B4DE 112010003895B4DE-112010003895-B4

Abstract

Methods for producing a fine metal structure, comprising wet etching or dry etching, Rinsing to remove contaminants that have formed after dry etching or wet etching, followed by rinsing with a processing fluid, Rinse with water after rinsing with the processing fluid, and dry after rinsing with water. wherein the processing fluid comprises at least one compound selected from the group consisting of: an imidazolium halide with an alkyl group containing 12, 14 or 16 carbon atoms; a pyridinium halide with an alkyl group containing 14 or 16 carbon atoms; a betaine compound with an alkyl group containing 12, 14 or 16 carbon atoms; and an amine oxide compound with an alkyl group containing 14, 16 or 18 carbon atoms, wherein the content of at least one compound in the processing fluid is from 10 ppm to 10 wt%.

Inventors

Masaru Ohto
Hiroshi Matsunaga
Kenji Yamada

Assignees

MITSUBISHI GAS CHEMICAL CO., INC.

Dates

Publication Date: 20260513
Application Date: 20100929
Priority Date: 20091002

Claims (14)

A process for producing a fine metal structure, comprising wet or dry etching, rinsing of impurities formed after dry or wet etching, subsequent rinsing with a processing fluid, rinsing with water after rinsing with the processing fluid, and drying after rinsing with water, the processing fluid comprising at least one compound selected from the group consisting of: an imidazolium halide having an alkyl group containing 12, 14, or 16 carbon atoms; a pyridinium halide having an alkyl group containing 14 or 16 carbon atoms; a betaine compound having an alkyl group containing 12, 14, or 16 carbon atoms; and an amine oxide compound with an alkyl group containing 14, 16 or 18 carbon atoms, where the content of at least one compound in the processing fluid is from 10 ppm to 10 wt%.
Method for producing a fine metal structure according to Claim 1 , in which the pattern of the fine metal structure contains tungsten.
Method for producing a fine metal structure according to Claim 1 or 2 , in which the fine metal structure is a semiconductor device or a micromachine.
Method for producing a fine metal structure according to one of the Claims 1 until 3 , wherein the processing fluid comprises at least one compound selected from the group consisting of: an imidazolium halide comprising a dodecyl group, a tetradecyl group or a hexadecyl group; a pyridinium halide comprising a tetradecyl group or a hexadecyl group; a betaine compound comprising a dodecyl group, a tetradecyl group or a hexadecyl group; and an amine oxide compound comprising a tetradecyl group, a hexadecyl group or an octadecyl group.
Method for producing a fine metal structure according to one of the Claims 1 until 4 , wherein the content of the at least one compound in the processing fluid is from 10 ppm to 5 wt%.
Method for producing a fine metal structure according to one of the Claims 1 until 5 , wherein the concentration of the at least one compound in the processing fluid ranges from 10 ppm to 1000 ppm.
Method for producing a fine metal structure according to one of the Claims 1 until 6 , wherein the processing fluid comprises dodecyldimethylaminoacetic acid betaine, palm oil fatty acid amide propyl betaine or both as a betaine compound.
Method for producing a fine metal structure according to one of the Claims 1 until 6 , wherein the processing fluid comprises dimethyltetradecylamine oxide, dimethylhexadecylamine oxide, dimethyloctadecylamine oxide or a combination thereof as an amine oxide compound.
Method for producing a fine metal structure according to one of the Claims 1 until 6 , wherein the processing fluid comprises an imidazolium halide comprising a C14 or C16 alkyl group.
Method for producing a fine metal structure according to one of the Claims 1 until 6 , wherein the processing fluid comprises an imidazolium halide comprising a C16 alkyl group.
Method for producing a fine metal structure according to one of the Claims 1 until 6 , wherein the processing fluid comprises a pyridinium halide comprising a C16 alkyl group.
Method for producing a fine metal structure according to one of the Claims 1 until 6 , wherein the processing fluid comprises an amine oxide compound comprising a C16 or C18 alkyl group.
Method for producing a fine metal structure according to one of the Claims 1 until 12 , wherein the processing fluid further comprises water.
Method for producing a fine metal structure according to one of the Claims 1 until 13 , comprising in the following order: wet or dry etching of silicon oxide to create etched areas, filling the etched areas and producing a fine metal structure, wherein the metal structure contains tungsten, a first rinsing of the fine metal structure with water after producing the fine metal structure, a rinsing of the fine metal structure with the processing fluid after the first rinsing, a second rinsing of the fine metal structure with water after rinsing with the processing fluid, and drying after the second rinsing with water.

Description

Technical field The present invention relates to a method for producing a fine metal structure in which a processing fluid is used to suppress pattern breakdown of the fine metal structure. State of the art Photolithography has been used as a method for creating and processing devices with fine structures, employed in a wide range of fields, including semiconductor devices, printed circuit boards, and the like. In these fields, significant advances are being made in semiconductor device size reduction, integration level increase, and speed increase, coupled with highly demanding performance requirements. This leads to a continuous miniaturization and increase in the aspect ratio of the photoresist pattern used in photolithography. However, the progress in miniaturizing photoresist patterns causes pattern breakdown, a serious problem. It is known that when a photoresist sample dries in a processing fluid used in wet processing (primarily a rinsing treatment to wash away the developer solution) after development, the collapse of the photoresist sample is caused by the stress resulting from the surface tension of the processing fluid. To prevent the collapse of the photoresist sample, methods have been proposed, such as replacing the rinsing fluid with a fluid having a low surface tension, using a non-ionic surfactant, a compound soluble in an alcohol solvent, or the like (see, for example, patent documents 1 and 2), and a method of hydrophobizing the surface of the photoresist sample (see, for example, patent document 3). In a fine structure formed by photolithography from a metal, metal nitride, metal oxide, or the like (hereinafter referred to as a "fine metal structure," and where a metal, metal nitride, metal oxide, or the like may hereinafter be collectively referred to as a "metal"), the strength of the metal itself forming the structure is greater than the strength of the photoresist pattern itself or the bond strength between the photoresist pattern and the substrate. Therefore, pattern breakdown of the structure is minimal compared to that of the photoresist pattern. However, with advances in size reduction, integration levels, and speeds in semiconductor devices and micromachines, pattern breakdown of the structure due to miniaturization and an increase in the aspect ratio of the photoresist pattern becomes a serious problem. The fine metal structure has a surface condition completely different from that of the photoresist pattern, which is an organic material, and therefore, there is no effective measure to prevent pattern breakdown of the structure. Accordingly, the current situation is such that the degree of freedom in designing the pattern for manufacturing a semiconductor device or a micromachine with reduced size, increased integration level, and increased speed is considerably restricted, since the pattern is necessarily designed to prevent pattern breakdown. Patent document 4 describes a cleaning agent for lithography and methods for producing resist patterns using this agent. State of the art documents Patent documents Patent document 1: JP 2004 - 184 648 APatent document 2: JP 2005 - 309 260 APatent document 3: JP 2006 - 163 314 APatent document 4: US 2009 / 0 004 608 A1 Summary of the invention Problems to be solved by the invention As described above, the current situation is such that in the field of fine metal structures, such as semiconductor devices and micromachines, no effective technique for suppressing pattern breakdown is known. The present invention was developed under these circumstances and an object of the present invention is to provide a method for producing a fine metal structure, such as a semiconductor device and a micromachine, in which a processing fluid is used that can suppress pattern breakdown of the fine metal structure. Means of solving the problems As a result of intensive investigations carried out by the inventors to solve the problem, it was found that the problem can be solved by a process comprising wet or dry etching, rinsing of impurities formed after dry or wet etching, subsequent rinsing with a processing fluid, rinsing with water after rinsing with the processing fluid, and drying after rinsing with water, wherein the processing fluid comprises at least one compound selected from the group consisting of: an imidazolium halide with an alkyl group containing 12, 14, or 16 carbon atoms; a pyridinium halide with an alkyl group containing 14 or 16 carbon atoms; a betaine compound with an alkyl group containing 12, 14, or 16 carbon atoms; and an amine oxide compound with an alkyl group containing 14, 16 or 18 carbon atoms, wherein the content of the at least one compound in the processing fluid is from 10 ppm to 10 wt%. The present invention was made on the basis of this knowledge. The main subject matter of the present invention is as defined in the attached claims. In the description, the cases where the number of carbon atoms in the alkyl group is 12, 1