Reduction Gas and Chemical Additive Effects on the MOCVD Copper Films Deposited From (hfac)Cu(1,5-DMCOD) as a Precursor

(hfac)Cu(1,5-DMCOD) 전구체를 이용한 MOCVD Cu 증착 특성에 미치는 환원기체와 첨가제의 영향에 관한 연구

  • Byeon, In-Jae (School of Metallurgical and Materials Engineering, Kookmin university) ;
  • Seo, Beom-Seok (School of Metallurgical and Materials Engineering, Kookmin university) ;
  • Yang, Hui-Jeong (School of Metallurgical and Materials Engineering, Kookmin university) ;
  • Lee, Won-Hui (School of Metallurgical and Materials Engineering, Kookmin university) ;
  • Lee, Jae-Gap (School of Metallurgical and Materials Engineering, Kookmin university)
  • 변인재 (국민대학교 금속재료공학부) ;
  • 서범석 (국민대학교 금속재료공학부) ;
  • 양희정 (국민대학교 금속재료공학부) ;
  • 이원희 (국민대학교 금속재료공학부) ;
  • 이재갑 (국민대학교 금속재료공학부)
  • Published : 2001.01.01

Abstract

The deposition characteristics of MOCVO Cu using the (hfac)Cu(I) (1,5-DMCOD)(1,1,1,5,5,5-hexafluoro-2,4-pentanedionato Cu(I) 1,5-dimethyl-cyclooctadine) as a precursor have been investigated in terms of the effects of hydrogen and H(hfac) ligand addition with He carrier gas. MOCVD Cu using a Helium carrier gas showed a low deposition rate (20~$125{\AA}/min$) at the substrate temperature range of 180~$230^{\circ}C$. Moreover, the Cu film deposited at 19$0^{\circ}C$ was very thin (~$700{\AA}$) and showed the lowest resistivity value of $2.8{\mu}{\Omega}-cm$. The deposition rate of MOCVD Cu using $H_2$or H(hfac) addition was significantly enhanced especially at the low temperature region (180~$190^{\circ}C$). Furthermore, thinner Cu films (~$500{\AA}$) provided low resistivity (3.6~$2.86{\mu}{\Omega}-cm$). From surface reflectance measurement, very thin films deposited by using different gas system revealed good surface morphology comparable with sputtered Cu film ($300^{\circ}C$, vacuum-anneal). Hence, Cu film using (hfac)Cu(1,5-DMCOD) as a precursor is expected as a good seed layer in the electrochemical deposition process for Cu metallization.

(hfac)Cu(1, 5-DMCOD)(1, 1, 1, 5, 5, 5-Hexafluoro-2, 4-pentanedionato Cu(I) 1, 5-dimethyl-cyclooctadine) 전구체와 He 운반기체를 이용하여 MOCVD(Metal Organic Chemical Vapor Deposition) 방법으로 Cu 박막을 형성하였으며, He 운반기체와 함께 $H_2$ gas 및 H(hfac) Ligand의 첨가가 Cu 박막 형성에 미치는 영향에 대하여 조사하였다. He운반기체만을 사용한 경우, Cu 박막의 증착율은 기판온도 180~$230^{\circ}C$에서 20~$125{\AA}/min$ 정도로 낮은 값을 보였으며, 특히 기판온도 $190^{\circ}C$에서는 매우 얇은 두께 ($700{\AA}$)이면서 낮은 비저항($2.8{\mu}{\Omega}cm$)을 갖는 Cu 박막이 형성됨을 알 수 있었다 He 운반기체와 함께 환원가스(H$_2$) 및 화학첨가제 (H (hfac) ligand)의 첨가 실험에서는 낮은 기판온도 ($180~190^{\circ}C$) 구간에서 현저하게 증착율이 증가하였으며 얇은 두께 (~$500{\AA}$)의 Cu 박막이 낮은 비저항(3.6~$2.86{\mu}{\Omega}cm$)을 갖는 것으로 나타났다. 또한 얇은 두께의 MOCVD Cu박막들의 표면 반사도(reflectance)는 $300^{\circ}C$에서 열처리한 sputter Cu의 반사도에 근접하는 우수한 surface morphology를 보였다 결국, (hfac)Cu(1,6-DMCOD) 전구체를 이용하여 얻어진 MOCVD Cu박막은 얇은 두께에서 낮은 비저항을 갖는 우수한 막질을 보였으며, Electrochemical deposition공정에서 conformal seed layer로써의 적용이 가능할 것으로 기대된다.

Keywords

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