The role of nickel and titanium in the formation of ohmic contacts on p-type 4H–SiC

Farah Laariedh (1, 2) , Mihai Lazar (1, 2) , P. Cremillieu (3) , J. Penuelas (4) , J-L Leclercq (5) , Dominique Planson (1, 2)

1 EE - Ampère, Département Energie Electrique
2 INSA Lyon - Institut National des Sciences Appliquées de Lyon
3 INL - Nanolyon - INL - Plateforme Technologique Nanolyon
4 INL - H&N - INL - Hétéroepitaxie et Nanostructures
5 INL - Photonique - INL - Nanophotonique

The formation of low resistivity ohmic contacts to p-type 4H–SiC is achieved. Transfer length method (TLM)-based structures were fabricated on 0.8 µm thick epitaxial p-type silicon carbide (4H–SiC) layers. TLM metal patterns were obtained by a lift-off procedure and electron beam deposition of Ni, Ti and Al. The electrical properties of the contacts were examined using current/voltage measurements. Contact resistivity as a function of annealing was investigated over the temperature range from 700 to 1000 °C. The lowest contact resistivity of 1.5 × 10−5 Ω cm2 was obtained for the Ni/Ti/Al/Ni contact after annealing at 800 °C for 90 s. Using secondary ion mass spectrometry, energy-dispersive x-ray spectroscopy and x-ray diffraction measurements, we quantitatively and qualitatively determined the formation and the nature of the ohmic contact to p-type SiC.

Mots clés: Silicon Carbide; Ohmic contact resistance; nickel silicide; titanium silicon carbide; SIMS; EDX and XRD

Domaines: Electronique

Farah Laariedh, Mihai Lazar, P. Cremillieu, J. Penuelas, J-L Leclercq, et al.. The role of nickel and titanium in the formation of ohmic contacts on p-type 4H–SiC. Semiconductor Science and Technology, 2013, 28 (4), ⟨10.1088/0268-1242/28/4/045007⟩. ⟨hal-01627844⟩