A processing system and platform for improving both the microscopic and macroscopic uniformity of materials during etching is disclosed herein. These improvements may be accomplished through the formation and dissolution of thin, self-limiting layers on the material surface by the use of wet atomic layer etching (ALE) techniques. For etching of polycrystalline materials, these self-limiting reactions can be used to prevent this roughening of the surface during etching. Thus, as disclosed herein, a wet ALE process uses sequential, self-limiting reactions to first modify the surface layer of a material and then selectively remove the modified layer.

As a rust prevention member that has excellent corrosion resistance, while being provided with a coating film that contains Si, a rust prevention member which is provided with a base material, a zinc-based plating layer that is provided on the base material, and a chemical conversion coating film that contains Si and is provided on the zinc-based plating layer is described. This rust prevention member is characterized in that the chemical conversion coating film has an Si-rich region on the surface side, said Si-rich region having an atomic ratio of the Si content to the Zn content of 1 or more, while having a thickness of 100 nm or more.

This invention provides a threaded connection for oil country tubular goods that exhibits excellent corrosion resistance and galling resistance, and a method for producing the threaded connection for oil country tubular goods. The method includes a ZnNi alloy plating layer formation step of forming a ZnNi alloy plating layer, and a chromate coating formation step of forming a chromate coating after the ZnNi alloy plating layer formation step. The chromate coating formation step includes a chromate treatment step and a drying step. The chromate coating formation step satisfy one or more conditions selected from the following conditions 1 to 3. Condition 1: stirring speed of the chromating solution in the chromate treatment step: a linear speed of 0.5 m/s or more; Condition 2: chromate treatment time in the chromate treatment step: less than 50 seconds; and Condition 3: drying temperature in the drying step: 60 C. or less.

This invention provides a threaded connection for oil country tubular goods that exhibits excellent corrosion resistance and galling resistance, and a method for producing the threaded connection for oil country tubular goods. The method includes a ZnNi alloy plating layer formation step of forming a ZnNi alloy plating layer, and a chromate coating formation step of forming a chromate coating after the ZnNi alloy plating layer formation step. The chromate coating formation step includes a chromate treatment step and a drying step. The chromate coating formation step satisfy one or more conditions selected from the following conditions 1 to 3. Condition 1: stirring speed of the chromating solution in the chromate treatment step: a linear speed of 0.5 m/s or more; Condition 2: chromate treatment time in the chromate treatment step: less than 50 seconds; and Condition 3: drying temperature in the drying step: 60 C. or less.

Methods for selective deposition of silicon oxide films on dielectric surfaces relative to metal surfaces are provided. A metal surface of a substrate may be selectively passivated relative to the dielectric surface, such as with a polyimide layer or thiol SAM. Silicon oxide is selectively deposited on the dielectric surface relative to the passivated metal surface by contacting the dielectric surface with a metal catalyst and a silicon precursor comprising a silanol.

Methods for selective deposition of silicon oxide films on dielectric surfaces relative to metal surfaces are provided. A metal surface of a substrate may be selectively passivated relative to the dielectric surface, such as with a polyimide layer or thiol SAM. Silicon oxide is selectively deposited on the dielectric surface relative to the passivated metal surface by contacting the dielectric surface with a metal catalyst and a silicon precursor comprising a silanol.

The method for forming a coating of the present invention includes: a first step of applying a first solution containing a polysilazane to a surface 2a of a metal substrate 2, heating the first solution to make the first solution undergo conversion into silica and form a first coating 1 having open defects 3, on the surface 2a of the metal substrate 2, and a second step of applying a second solution containing a polysilazane to a surface 1a of the first coating 1 to fill the open defects 3, and heating the second solution at a temperature lower than a heating temperature in the first step to make the second solution undergo conversion into silica and form a second coating 5 on a surface 1a of the first coating 1.

The method for forming a coating of the present invention includes: a first step of applying a first solution containing a polysilazane to a surface 2a of a metal substrate 2, heating the first solution to make the first solution undergo conversion into silica and form a first coating 1 having open defects 3, on the surface 2a of the metal substrate 2, and a second step of applying a second solution containing a polysilazane to a surface 1a of the first coating 1 to fill the open defects 3, and heating the second solution at a temperature lower than a heating temperature in the first step to make the second solution undergo conversion into silica and form a second coating 5 on a surface 1a of the first coating 1.

A chemical surface treatment method of a metal improves bonding of different materials in which first pores are formed in the surface of the metal and second pores are formed locally in the surfaces of the first pores by appropriately setting the number of repetitions of alkali treatment and acid treatment, the concentrations of treatment solutions, and treatment temperatures and times using the treatment solutions. The method includes performing the alkali treatment by immersing the metal in a base solution, so as to form first pores in a surface of the metal. The method further includes performing the acid treatment by immersing an alkali-treated result product in an acid solution, so as to form second pores locally in surfaces of the first pores.

A chemical surface treatment method of a metal improves bonding of different materials in which first pores are formed in the surface of the metal and second pores are formed locally in the surfaces of the first pores by appropriately setting the number of repetitions of alkali treatment and acid treatment, the concentrations of treatment solutions, and treatment temperatures and times using the treatment solutions. The method includes performing the alkali treatment by immersing the metal in a base solution, so as to form first pores in a surface of the metal. The method further includes performing the acid treatment by immersing an alkali-treated result product in an acid solution, so as to form second pores locally in surfaces of the first pores.