TY - JOUR
T1 - On the specific contact resistance of metal contacts to p-type GaN
AU - Lewis, L.
AU - Maaskant, P. P.
AU - Corbett, B.
PY - 2006/12/1
Y1 - 2006/12/1
N2 - Extraction of the specific contact resistance, ρc, using the established circular transmission line measurement (c-TLM) and a series resistance measurement across mesa-isolated diodes is compared for a non-alloyed Pd/Ag contact to p-GaN. The limitations of the c-TLM technique are discussed and it is shown that for ρc values below 10-4 Ω cm2 both unintentional submicron errors in the actual radii and uncertainty in the resistance measurements can lead to order of magnitude changes in the extracted ρc. An additional current-voltage measurement across a mesa-isolated diode is proposed. The accuracy of the extracted ρc in this case requires consistency of the intrinsic diode characteristic, namely the ideality, at the bias voltages used for extraction, which is in turn related to the carrier transport and recombination properties. From a comparison with the c-TLM, we conclude that the resistance should be extracted at current densities <10 A cm-2 as junction heating changes the diode ideality.
AB - Extraction of the specific contact resistance, ρc, using the established circular transmission line measurement (c-TLM) and a series resistance measurement across mesa-isolated diodes is compared for a non-alloyed Pd/Ag contact to p-GaN. The limitations of the c-TLM technique are discussed and it is shown that for ρc values below 10-4 Ω cm2 both unintentional submicron errors in the actual radii and uncertainty in the resistance measurements can lead to order of magnitude changes in the extracted ρc. An additional current-voltage measurement across a mesa-isolated diode is proposed. The accuracy of the extracted ρc in this case requires consistency of the intrinsic diode characteristic, namely the ideality, at the bias voltages used for extraction, which is in turn related to the carrier transport and recombination properties. From a comparison with the c-TLM, we conclude that the resistance should be extracted at current densities <10 A cm-2 as junction heating changes the diode ideality.
UR - https://www.scopus.com/pages/publications/33846885455
U2 - 10.1088/0268-1242/21/12/041
DO - 10.1088/0268-1242/21/12/041
M3 - Article
AN - SCOPUS:33846885455
SN - 0268-1242
VL - 21
SP - 1738
EP - 1742
JO - Semiconductor Science and Technology
JF - Semiconductor Science and Technology
IS - 12
M1 - 041
ER -