Controlling the properties of metal contacts (Schottky or Ohmic) to p-type wide band gap semiconductors SiC and GaN is an important physical issue, owing to the potential implications in power devices technologies. This work reports on the properties of Ti/Al-based contacts to p-type 4H-SiC and p-type GaN, monitored using different techniques. In particular, in the case of p-type SiC, Ti/Al and Ti/Al/W contacts showed an Ohmic behavior at 900-1100°C (with rc = 1.5 - 6x10-4Ohmxcm2), attributed to the formation of Ti- and Al-containing phases at the interface and in the stack. In the case of p-type GaN, Ti/Al contacts were studied to be used as Schottky gate in HEMTs. Temperature-dependent measurements allowed to determine a variation of the Schottky barrier height from 2.08 eV to 1.60 eV upon annealing at 800°C. Comparison with other metals are reported through the paper.
Study of Ti/Al-based Metal Contacts to p-type SiC and GaN
F Roccaforte;M Vivona;G Greco;R Lo Nigro;F Giannazzo;S Di Franco;C Bongiorno;
2016
Abstract
Controlling the properties of metal contacts (Schottky or Ohmic) to p-type wide band gap semiconductors SiC and GaN is an important physical issue, owing to the potential implications in power devices technologies. This work reports on the properties of Ti/Al-based contacts to p-type 4H-SiC and p-type GaN, monitored using different techniques. In particular, in the case of p-type SiC, Ti/Al and Ti/Al/W contacts showed an Ohmic behavior at 900-1100°C (with rc = 1.5 - 6x10-4Ohmxcm2), attributed to the formation of Ti- and Al-containing phases at the interface and in the stack. In the case of p-type GaN, Ti/Al contacts were studied to be used as Schottky gate in HEMTs. Temperature-dependent measurements allowed to determine a variation of the Schottky barrier height from 2.08 eV to 1.60 eV upon annealing at 800°C. Comparison with other metals are reported through the paper.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
