| 摘要 |
PURPOSE:To obtain a light emitting element which does not decrease its bondability by using chromium (Cr) as a protective film disposed on the lowermost layer of an electrode, so that the protective film is a high temperature treated film, thereby protecting a compound semiconductor against an etchant. CONSTITUTION:A compound semiconductor 10 is first set in a vacuum chamber, Cr prepared in advance by an electron beam is deposited to form a protective film 21. Then, it is heated to approx. 300 deg.C, held for the prescribed time to anneal the Cr film. Thereafter, it is again set to the original temperature and vacuum conditions to form the second electrode layer 22 which mainly contains Ge and the third electrode layer 23 which mainly contains Au. When the deposition is finished, a photosensitive film is patterned by a photolithographic technique, and an Au-Ge layer is etched with iodine potassium iodide mixture solution. Thereafter, Cr is etched with mixture of second sellium ammonium nitrate, perchloric acid and water. The protective film made of Cr may be practical if the thickness is less than 100Angstrom according to the ohmic annealing. |
