Abstract: The invention has for its object the provision of a cleaner capable of removing particles and metal impurities present on the surface of a wafer without corrosion of wirings, gates or the like yet at normal temperature in a short period of time and with a one-pack type solution. To accomplish the above object, the invention provides a cleaner that is an aqueous solution containing phosphoric acid, hydrofluoric acid, and ammonia and/or amine, and having a pH ranging from 2 to 12, wherein the aqueous solution comprises 0.5 to 25 mass % of phosphoric acid, 0.1 to 10 mass % of ammonia and/or amine, and 5×10?3 to 5.0 mass % of hydrofluoric acid.

Abstract: The invention has for its object the provision of a cleaner capable of removing particles and metal impurities present on the surface of a wafer without corrosion of wirings, gates or the like yet at normal temperature in a short period of time and with a one-pack type solution. To accomplish the above object, the invention provides a cleaner that is an aqueous solution containing phosphoric acid, hydrofluoric acid, and ammonia and/or amine, and having a pH ranging from 2 to 12, wherein the aqueous solution comprises 0.5 to 25 mass % of phosphoric acid, 0.1 to 10 mass % of ammonia and/or amine, and 5×10?3 to 5.0 mass % of hydrofluoric acid.

Abstract: Disclosed is an apparatus for inverse photoemission spectroscopy in which optical filters having at least two different cutoff energies are selectively provided in the optical path of a vacuum ultraviolet-ray detector. The bandpass characteristic of emitted light obtained by causing monochromatic energy to impinge upon a sample is obtained by different high cutoff energies of the two filters. The different high cutoff energies are set by selection of different types of ionic crystals and the temperature characteristic of the same or different types of ionic crystals.