To provide a Sn-based plated steel sheet capable of exhibiting superior corrosion resistance, yellowing resistance, coating film adhesiveness, and sulphide stain resistance without using a chromate film. A Sn-based plated steel sheet of the present invention includes: a steel sheet; a Sn-based plating layer located on at least one surface of the steel sheet; and a coating layer located on the Sn-based plating layer, wherein the Sn-based plating layer contains 1.0 g/m.sup.2 to 15.0 g/m.sup.2 of Sn per side in terms of metal Sn, the coating layer contains zirconium oxide, and a content of the zirconium oxide is 1.0 mg/m.sup.2 to 10.0 mg/m.sup.2 per side in terms of metal Zr, the zirconium oxide includes zirconium oxide with an amorphous structure, and a crystalline layer whose main component is zirconium oxide with a crystalline structure is present on an upper layer of the zirconium oxide with the amorphous structure.

A method of detecting space debris includes: generating a virtual space debris in accordance with the law of conservation of mass by applying a debris breakup model to an object of breakup origin; calculating an orbit of each virtual space debris based on a debris orbit propagation model; and generating appearance frequency distribution of a motion vector of each virtual space debris on the celestial sphere based on the orbit calculation. The above operations are executed multiple times. The method further includes setting a search range vector based on a motion vector having a high level of the appearance frequency distribution of the motion vector, and applying a stacking method to regions in images captured at time intervals during the fixed point observation, the regions being shifted along the search range vector sequentially in the order of capture, thereby detecting space debris appearing on the images.

A method of detecting space debris includes: generating a virtual space debris in accordance with the law of conservation of mass by applying a debris breakup model to an object of breakup origin; calculating an orbit of each virtual space debris based on a debris orbit propagation model; and generating appearance frequency distribution of a motion vector of each virtual space debris on the celestial sphere based on the orbit calculation. The above operations are executed multiple times. The method further includes setting a search range vector based on a motion vector having a high level of the appearance frequency distribution of the motion vector, and applying a stacking method to regions in images captured at time intervals during the fixed point observation, the regions being shifted along the search range vector sequentially in the order of capture, thereby detecting space debris appearing on the images.

Provided is an electroplating solution of tin or a tin alloy in which the thickness variation of wafer bumps is maintained at a low level even in various changes of plating conditions and thus the mass productivity is improved. The electroplating solution of tin or a tin alloy may include tin ions as metal ions, a conductive salt, a carboxylic acid as a structure refiner, and a combination of a flavone compound and a quaternary ammonium compound as a thickness variation improving agent.

Provided is an electroplating solution of tin or a tin alloy in which the thickness variation of wafer bumps is maintained at a low level even in various changes of plating conditions and thus the mass productivity is improved. The electroplating solution of tin or a tin alloy may include tin ions as metal ions, a conductive salt, a carboxylic acid as a structure refiner, and a combination of a flavone compound and a quaternary ammonium compound as a thickness variation improving agent.

An electroplating bath for depositing a silver/tin alloy on a substrate. The electroplating bath comprises (a) a source of tin ions; (b) a source of silver ions; (c) an acid; (d) a first complexing agent; (e) a second complexing agent, wherein the second complexing agent is selected from the group consisting of allyl thioureas, aryl thioureas, and alkyl thioureas, and combinations thereof; and (f) optionally, a wetting agent, and (g) optionally, an antioxidant.

An electroplating bath for depositing a silver/tin alloy on a substrate. The electroplating bath comprises (a) a source of tin ions; (b) a source of silver ions; (c) an acid; (d) a first complexing agent; (e) a second complexing agent, wherein the second complexing agent is selected from the group consisting of allyl thioureas, aryl thioureas, and alkyl thioureas, and combinations thereof; and (f) optionally, a wetting agent, and (g) optionally, an antioxidant.

The disclosure provides a Sn—In electroplating bath that is Pb-free, environmentally safe, operates at room temperature, and does not require changes in existing plating assemblies. Room temperature aging and limited thermal cycling tests show that the electroplated Sn—In alloy film on a Cu substrate effectively mitigates whisker growth.

The disclosure provides a Sn—In electroplating bath that is Pb-free, environmentally safe, operates at room temperature, and does not require changes in existing plating assemblies. Room temperature aging and limited thermal cycling tests show that the electroplated Sn—In alloy film on a Cu substrate effectively mitigates whisker growth.

A tin plating solution and a method for fabricating a semiconductor device are provided. The tin plating solution comprises tin ions supplied from a soluble tin electrode, an aliphatic sulfonic acid having a carbon number of 1 to 10, an anti-oxidant, a wetting agent, and a grain refiner that is an aromatic carbonyl compound.