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US010648087B2 (12 ) United States Patent ( 10 ) Patent No.: US 10,648,087 B2 Lansalot -Matras et al. (45 ) Date of Patent : May 12 , 2020 (54 ) ETCHING REACTANTS AND PLASMA - FREE (51 ) Int. CI. ETCHING PROCESSES USING THE SAME C23F 1/12 (2006.01 ) HOIL 21/311 (2006.01 ) ( 71) Applicants :L’Air Liquide, Société Anonyme pour ( Continued ) l'Etude et l'Exploitation des Procédés (52 ) U.S. Ci. Georges Claude, Paris (FR ) ; Clément CPC C23F 1/12 ( 2013.01) ; C23C 8/80 Lansalot- Matras , Princeton , NJ (US ) ; (2013.01 ) ; HOIL 21/31116 ( 2013.01 ) ; Jooho Lee , Seoul (KR ) ; Jean -Marc ( Continued ) Girard , Versailles ( FR ) ; Nicolas (58 ) Field of Classification Search Blasco , Grenoble (FR ) ; Satoko CPC C23F 1/12 Gatineau , Seoul (KR ) See application file for complete search history. ( 72 ) Inventors: Clément Lansalot- Matras , Princeton , (56 ) References Cited NJ (US ) ; Jooho Lee, Seoul (KR ) ; Jean -Marc Girard , Versailles ( FR ) ; U.S. PATENT DOCUMENTS Nicolas Blasco , Grenoble (FR ) ; Satoko 4,343,676 A 8/1982 Tarng Gatineau , Seoul (KR ) 4,793,897 A 12/1988 Dunfield et al . ( 73 ) Assignee : L’Air Liquide, Société Anonyme pour ( Continued ) l'Exploitation et l'Etude des Procédés Georges Claude, Paris (FR ) FOREIGN PATENT DOCUMENTS JP H09 228053 9/1997 ( * ) Notice : Subject to any disclaimer, the term of this JP H10 113536 5/1998 patent is extended or adjusted under 35 U.S.C. 154 ( b ) by 0 days . (Continued ) (21 ) Appl. No.: 15 /774,892 OTHER PUBLICATIONS Aarik , J. et al. , “Mechanisms of suboxide growth and etching in ( 22 ) PCT Filed : Sep. 1 , 2016 atomic layer deposition of tantalum oxide from TaCl, and H20 , " Applied Surface Science 103 ( 1996 ), 331-341. ( 86 ) PCT No.: PCT/ US2016 / 049857 (Continued ) § 371 ( c ) ( 1 ) , ( 2 ) Date : May 9 , 2018 Primary Examiner Roberts P Culbert (74 ) Attorney , Agent, or Firm — Yan Jiang ; Patricia E. ( 87 ) PCT Pub . No.: WO2016 / 172740 McQueeney PCT Pub . Date : Oct. 27 , 2016 (57 ) ABSTRACT (65 ) Prior Publication Data Disclosed are processes of removing layers from substrates US 2018/0327913 A1 Nov. 15 , 2018 using fluorinated reactants having the formula MF_( adduct) n ' wherein x ranges from 2 to 6 inclusive; n ranges from 0 to 5 inclusive; M is selected from the group consisting of P , Related U.S. Application Data Ti, Zr, Hf, V , Nb , Ta ,Mo , and W ; and the adduct is a neutral (60 ) Provisional application No.62 / 253,507 , filed on Nov. organic molecule selected from THF , dimethylether, diethy 10 , 2015 . (Continued ) 6 M 3 8 11 2 11 9 US 10,648,087 B2 Page 2 lether , glyme , diglyme, triglyme, polyglyme , dimethylsul FOREIGN PATENT DOCUMENTS phide , diethylsulphide, or methylcyanide . The fluorinated reactants dry etch the nitride layers without utilizing any JP 2007 141918 6/2007 plasma. WO WO 2015 194178 12/2015 16 Claims, 12 Drawing Sheets OTHER PUBLICATIONS Baroch , C.J. et al. , “ Preparation of zirconium from zirconium tetrafluoride, ” U.S. Atomic Energy Commission , Physical Sciences ( 51 ) Int. Cl. Reading Room , Unclassified ISC - 720 , Ames Laboratory , Iowa State HOIL 213213 ( 2006.01) College, May 31 , 1956 , 1-18 . HOIL 21/67 (2006.01 ) Jenkins , W.A. et al. , “ Tantalum oxychloride, " J. Inorg . Nucl . Chem . C23C 8/80 ( 2006.01) 1959 , 11 , 163-164 . HOIL 21/02 (2006.01 ) Knapas, K. et al. , “ Etching of Nb205 thin films by NbC15 ," Chem . B08B 9/08 ( 2006.01 ) Vap. Deposition 2009 , 15, 269-273 . ( 52 ) U.S. Ci. Kukli , K. et al ., " Atomic layer deposition of tantalum oxide thin CPC .. HOIL 21/31122 ( 2013.01 ) ; HOIL 21/32135 films form iodide precursor, ” Chem . Mater . 2001, 13 , 122-128 . ( 2013.01 ) ; HOIL 21/67069 (2013.01 ) ; B08B Mercier , F. et al. , “ Niobium nitride thin films deposited by high 9/083 (2013.01 ) ; HOIL 21/02244 ( 2013.01 ) ; temperature chemical vapor deposition ,” Surface & Coatings Tech HOIL 21/02247 (2013.01 ) nology 260 (2014 ) 126-132 . Sha , L. et al. , “ Ion -enhanced chemical etching of ZrO2 in a chlorine ( 56 ) References Cited discharge, " J. Vac . Sci . Technol. A 20 ( 5 ), Sep./Oct. 2002 , 1525 1531 . U.S. PATENT DOCUMENTS Sha , L. et al. , “ Plasma etching selectivity of ZrO2 to Si in BC12/ C12 5,855,689 A 1/1999 Akiyama plasmas, ” J. Vac . Sci. Technol. A 21 (6 ) , Nov./Dec. 2003 , 1915-1922 . 5,879,646 A 3/1999 Orihara et al . Sungauer, E. et al. , “ Etching mechanisms of HfO2, SiO2, and 6,077,451 A 6/2000 Takenaka et al. poly -Si substrates in BC1z plasmas , " J. Vac . Sci. Technol. B 25 ( 5 ) , 6,143,191 A 11/2000 Baum et al. Sep./Oct. 2007 , 1640-1646 . 6,261,934 B1 7/2001 Kraft et al. Woo , J.-C. et al. , “ A study on dry etching for profile and selectivity 6,284,052 B2 9/2001 Nguyen et al. of ZrO2 thin films over Si by using high density plasma, ” Thin Solid 9,130,158 B1 9/2015 Shen et al. 9,391,267 B2 7/2016 Shen et al. Films 517 (2009 ) , 4246-4250 . 2005/0019977 Al 1/2005 Shiva International Search Report and Written Opinion for corresponding 2005/0082002 A1 4/2005 Sato et al. PCT// US2016 / 049857 , dated Dec. 19 , 2016 . 2015/0050807 A1 * 2/2015 Wu HO1L 21/28556 438/669 * cited by examiner U.S. Patent May 12 , 2020 Sheet 1 of 12 US 10,648,087 B2 6 3 8 1 2 11 9 FIG 1 6 7 - 3 co 1 - - -1 - 1 2 8 1 11 14 FIG 2 U.S. Patent May 12 , 2020 Sheet 2 of 12 US 10,648,087 B2 5 ** O * 4.44 64 Y$ > g Sii $ ***** FIG 3 U.S. Patent May 12 , 2020 Sheet 3 of 12 US 10,648,087 B2 302 106 300 301 201 103 200 101 102. ) 1400 105 108 FIG 4 U.S. Patent May 12 , 2020 Sheet 4 of 12 US 10,648,087 B2 50 Nb205 Etchingrate[A/sec] 40 Ta205 A ZrO2 30 X HfO2 * TiO2 X X O Al2O3 10 + SIO2 0 250 270 290 310 330 350 370 390 410 Temperature [ ° C ] FIG 5 U.S. Patent May 12 , 2020 Sheet 5 of 12 US 10,648,087 B2 160 Nb205 OTa205 120 AZrO2 Etchingrate(A/sec) XHfO2 ?TiO2 X OA1203 + SiO2 20 ATIN 100 150 200 250 300 350 Temperature ( ° C ) FIG6 U.S. Patent May 12 , 2020 Sheet 6 of 12 US 10,648,087 B2 Nb205 350 OTa205 X 300 AZrO2 pong 250 XHfO2 Etchingrate(A/sec) 200 XTIO2 150 X OAI203 + SiO2 ? -S?N 50 CE 100 200 250 300 350 Temperature (° C ] FIG 7 U.S. Patent May 12 , 2020 Sheet 7 of 12 US 10,648,087 B2 Metallic layer Substrate Oxidation / Nitrization Metal oxide / nitride layer Metallic layer Substrate Etching Metallic layer Substrate Oxidation / Nitrization Metal oxidel nitride layer Metallic layer Substrate Etching Metallic layer Substrate Oxidation / Nitrization Metal oxidel nitride layer Substrate Etching Substrate FIG 8 U.S. Patent May 12 , 2020 Sheet 8 of 12 US 10,648,087 B2 WO w SIOL FIG 9a TINTI SiO2 lum FIG 9b U.S. Patent May 12 , 2020 Sheet 9 of 12 US 10,648,087 B2 Wo TINTI SiO , lum FIGFIG 909c Wo. W TINTI lum FIG 9d U.S. Patent May 12 , 2020 Sheet 10 of 12 US 10,648,087 B2 Tungsten oxide Tungsten TINTI FIG 10 U.S. Patent May 12 , 2020 Sheet 11 of 12 US 10,648,087 B2 Tungsten oxide 2 Tungsten FIG 11a Tungsten oxide Tungsten7 FIG 11b Tunesien oxida Tungste FIG 110 U.S. Patent May 12 , 2020 Sheet 12 of 12 US 10,648,087 B2 Tungsten oxide Tungsten FIG 12a Tungsten oxide Tungsten VINNN FIG 12b Tungsten FIG 12c US 10,648,087 B2 1 2 ETCHING REACTANTS AND PLASMA- FREE pressing the silicon etch rate (Sha et al ., J. Vac . Sci . Technol. , ETCHING PROCESSES USING THE SAME A 21 (2003 ) 1915 ) ; and an investigation of the etching characteristics ( etch rate , selectivity to Si) of ZrO2 thin films CROSS REFERENCE TO RELATED in the HBr/ SF high density plasma system ( Woo et al. , Thin APPLICATIONS 5 Solid Films 517 (2009 ) 4246-4250 ) . Dry plasma etching processes have some disadvantages The present application is a 371 of International PCT such as the cost of the equipment, the use of toxic or Application PCT /US2016 / 049857 , filed Sep. 1 , 2016 , which corrosive gases , and potential damage to the underlying claims the benefit of U.S. Provisional Application Ser. No. substrate . 62 /253,507 filed Nov. 10 , 2015 , herein incorporated by 10 H. Schafer (Z. Anorg . Allg . Chem . 1960, 305 , 341 ) and W. reference in its entirety for all purposes . A. Jenkins ( J. Inorg . Nucl . Chem . 1959 , 11, 163 ) described the thermal etching process of Tantalum oxide ( Ta203) at TECHNICAL FIELD temperatures between 200 and 350 ° C. according to the Disclosed are thermal processes of removing layers from 15 equation Ta ,05 ( ) + 3TaCl: ( ) > 5 TaOC13 ( g ). The reaction is substrates using fluorinated reactants having the formula endothermic ( ~ 35 kcal/ mol ) and an increase of the etching MF ( adduct) n , wherein x ranges from 2 to 6 inclusive ; n rate with temperature was observed . Nonetheless, the etch ranges from 0 to 5 inclusive ; M is an element selected from ing rate was too slow ( ~6x10-2 A /Cy ) to be suitable to the group consisting of P , Ti, Zr, Hf, V , Nb, Ta, Mo, and W ; replace existing plasma based processes. Knapas et al . and the adduct is a neutral organic molecule selected from 20 (Chem . Vap . Deposition 2009, 15 , pp . 269-273) found that THF, dimethylether , diethylether, glyme , diglyme, triglyme , NbCl, etches Nb20 , film producing volatile NbOC1z .
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    Manuscript including Title Page & Abstract First Principles Study on the Formation of Yttrium Nitride in Cubic and Hexagonal Phases G. Soto, M.G. Moreno-Armenta and A. Reyes-Serrato Centro de Ciencias de la Materia Condensada, Universidad Nacional Autónoma de México, Apartado Postal 356, Ensenada, Baja California. CP 22800, México. Abstract We have studied the formation of yttrium nitride in which the Y-atoms were arranged in two common close-packed stacking: The AB-stacking (hcp-symmetry) is the ground state of metallic yttrium; while the ABC-stacking (fcc-symmetry) is the ground state of yttrium nitride. Given the different symmetries between YN and Y, there must be a phase transition (hcp → fcc) as N is incorporated in the Y-lattice. By means of first principles calculations we have made a systematical investigation where N was gradually incorporated in octahedral interstices in AB and ABC stacking of Y. We report the heat of formation, bulk modulus, lattice parameter and electronic structure of the resultant nitrides. We found that both metal arrangements are physically achievable. Furthermore, for low nitrogen incorporation the two phases may coexist. However for high nitrogen concentration the cubic phases are favored by a 30 kJ mol-1 margi n. These results are important since fcc-YN is semiconducting and could be utilized as active layer in electronic devices. PACS: 71.15.Nc; 71.20.-b; 71.20.Be; 71.20.Lp; 71.20.Nr; 72.80.Ga Keywords: Yttrium nitride; Interstitial alloys; Transition metal nitrides; Ab initio; DFT; LAPW 1 Introduction The Transition (T) Metal (M) Nitrides (N) are valuable for several technological applications.
  • Harrison School District Chemical Hygiene Plan

    Harrison School District Chemical Hygiene Plan

    Harrison School District Chemical Hygiene Plan Updated & Approved by Mark Wilsey on 10-11-2019 Table of Contents Introduction and Overview .................................................................................................... 3 Section I: Annual Review ................................................................................................................ 3 Section II: Laboratory Hazardous Materials and Chemical Management .......................................... 3 Section II (a): Administrative Positions and Duties ......................................................................................... 3 Section III: Purchasing Procedures .................................................................................................. 4 Section IV: On-Site Hazardous Materials and Chemical Management ............................................... 5 Management of Chemicals .................................................................................................... 8 Acquisition of Chemicals ................................................................................................................. 8 General Rules and Procedures ........................................................................................................ 8 Inventory and Tracking ................................................................................................................... 9 Safety Data Sheets ........................................................................................................................