(10)  Patent No.:  US 7,404,910 Bl  Jul. 29, 2008  (45)  Date of Patent:  c12)  United States Patent  Kezuka et al.  (54)  ETCHING SOLUTION, ETCHED ARTICLE  AND METHOD FOR ETCHED ARTICLE  (75)  Inventors:  Takehiko Kezuka,  Settsu (JP);  Makoto  Suyama,  Settsu (JP);  Mitsushi Itano,  Settsu (JP)  (73)  Assignee:  Daikin Industries, Ltd.,  Osaka (JP)  ( *)  Notice:  Subject to any disclaimer, the term ofthis  patent is extended or adjusted under 35  U.S.C. 154(b) by  O  days.  (21)  Appl. No.:  09/856,358  (22)  PCT Filed:  Nov. 22, 1999  (86)  PCT No.:  PCT  I  JP99/06502  § 371 (c)(l),  (2), ( 4) Date:  May 22, 2001  (87)  PCT Pub. No.:  WO00/31785  PCT Pub. Date:  Jun. 2, 2000  (51)  Int. Cl.  B44C 1122  (2006.01)  (52)  U.S. Cl.  .......................  216/103;  216/106; 216/108;  252/79.1; 252/79.2  (58)  Field of Classification Search  ................. 438/745,  438/756; 252/79.1, 79.2, 79.3, 79.4; 257/636;  216/103  See application file for complete search history.  (57)  ABSTRACT  8 Claims, No Drawings  (56)  References Cited  U.S. PATENT DOCUMENTS  (30)  Foreign Application Priority Data  FOREIGN PATENT DOCUMENTS  An etching solution which contains hydrogen fluoride (HF)  and exhibits an etching rate ratio: etching rate for a boron› glass film (BSG) or boron-phosphorus-glass film (BPSG)/  etching rate for a thermally oxidized film (THOX) of 10 or  more at 25°  C.  3,518,135 A  6/1970 Cerniglia et al.  Nov. 24, 1998  (JP)  ................................. 10-332782  (74)Attorney, Agent, or Firm-B.  Aaron Schulman; Stites &  Harbison PLLC  Primary Examiner-Binh  X Tran  Assistant Examiner-Maki  Angadi  * cited by examiner  EP  EP  EP  EP  JP  JP  JP  JP  JP  JP  WO  0 669 646  0 887 323  1150342 Al  *  1168424 Al  52-56869  1977-056869  58-204540  1983-204540  60-64437  11-74249  WO 94/27314  8/1995  12/1998  10/2001  1/2002  5/1977  5/1977  11/1983  11/1983  4/1985  3/1999  11/1994  3,968,565  A  *  3,977,925  A  3,997,381  A  *  4,052,253  A  4,273,826  A  *  4,395,304  A  5,112,437 A  *  5,294,568  A  5,439,553  A  *  5,571,375  A  5,658,417 A  *  5,716,535  A  5,783,495  A  *  5,824,601  A  7/1976 Bertens et al. ................. 438/3  8/1976 Schwabe .................... 438/424  12/1976 Wanlass ........................ 156/3  10/ 1977 Kingzett  6/1981  McCollister et al ...... 428/310.5  7/1983 Kern et al.  5/1992 Watanabe et al. ........... 156/646  3/1994 McNeilly et al. ............ 438/706  8/1995 Grant et al. ................... 216/58  11/1996 Izumi et al.  8/1997 Watanabe et al. ........... 156/345  2/1998 Lee et al. ...................... 216/99  7/1998 Li et al. ...................... 438/738  10/1998 Dao et al.  US007404910Bl 