(19)
(11) EP 0 726 590 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
11.12.1996 Bulletin 1996/50

(43) Date of publication A2:
14.08.1996 Bulletin 1996/33

(21) Application number: 96102013.8

(22) Date of filing: 12.02.1996
(51) International Patent Classification (IPC)6: H01J 9/02
(84) Designated Contracting States:
DE FR GB

(30) Priority: 13.02.1995 JP 23582/95

(71) Applicant: NEC CORPORATION
Tokyo (JP)

(72) Inventor:
  • Kaihara, Toshio
    Ohtsu-shi, Shiga (JP)

(74) Representative: Baronetzky, Klaus, Dipl.-Ing. et al
Patentanwälte Dipl.-Ing. R. Splanemann, Dr. B. Reitzner, Dipl.-Ing. K. Baronetzky Tal 13
80331 München
80331 München (DE)

   


(54) Method for forming a field emission cold cathode


(57) The present invention provides a method for reshaping up a cone-like electrode (3) which is made of a refractory metal containing silicon. The method comprises the following steps. A surface of the cone-like electrode (3) is subjected to an oxidation of silicon which is contained in the refractory metal. The oxidation is generated at rates which increase toward a top portion of the cone-like electrode. As a result, a silicon oxide film (9) is formed, which coats the cone-like electrode (3). The silicon oxide film (9) has thickness which gradually increase toward a bottom portion of the cone-like electrode (3). An interface between the silicon oxide film (9) and the cone-like electrode (3) has sloped angles which increase toward the top portion. The silicon oxide film (9) is removed to thereby expose a reshaped cone electrode (3) which has a sharply pointed top. The reshaped cone electrode (3) has a surface having sloped angles which increase toward the sharply pointed top.






Search report