## Abstract

Contact resistivity between tungsten and in situ impurity (P and B)-doped Si _{1-x-y} Ge _{x} C _{y} films with 0 ≤ x ≤ 0.7, 0 ≤ y ≤ 0.02 has been investigated. In the case of the P-doped Si _{1-x-y} Ge _{x} C _{y} films, the contact resistivity decreases with increasing the carrier concentration, independently of the Ge and C fraction. Because P atoms become electrically inactive with increasing the Ge and C fractions, lower Ge and C fractions are necessary to reduce the contact resistivity. By growing the multi-layer P-doped epitaxial Si with a high carrier concentration of 4 × 10 ^{20} cm ^{-3} at a very low temperature of 450 °C on the P-doped Si _{1-x-y} Ge _{x} C _{y} film, very low contact resistivity of 6.5 × 10 ^{-8} Ω cm ^{2} is achieved. On the other hand, in the case of the B-doped Si _{1-x-y} Ge _{x} C _{y} films, the contact resistivity decreases with increasing the Ge fraction and scarcely depends on C fraction at a specified carrier concentration, and is typically 25 and 57% lower for x = 0.44 and 0.7 than that for Si, respectively. For the B-doped Si _{0.56} Ge _{0.44} films with a high carrier concentration of 6 × 10 ^{20} cm ^{-3} , very low contact resistivity is obtained to be 3.8 × 10 ^{-8} Ω cm ^{2} . These results demonstrate that low contact resistivity is caused by the lowering of schottky barrier height between metal and the B-doped film, due to the valence band shift.

Original language | English |
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Pages (from-to) | 679-683 |

Number of pages | 5 |

Journal | Applied Surface Science |

Volume | 212-213 |

Issue number | SPEC. |

DOIs | |

Publication status | Published - 2003 May 15 |

Externally published | Yes |

## Keywords

- CVD
- Contact resistivity
- Impurity doping
- Si Ge C
- Tungsten

## ASJC Scopus subject areas

- Chemistry(all)
- Condensed Matter Physics
- Physics and Astronomy(all)
- Surfaces and Interfaces
- Surfaces, Coatings and Films