Properties of Au-Zn Ohmic contacts to p-GaSb

Abstract

Electrical and metallurgical behavior of Au/Zn contacts to ptype indium phosphide Quantitative analysis of arsenic losses during the formation of Au(Zn)/pGaAs ohmic contacts Ohmic contacts to p-GaSb were prepared by the deposition of (100 A Au + 100 A Zn + 800 A Au) and their characteristics were analyzed. Measurements of specific contact resistance as a function of annealing temperature show a minimum value of ~ 1 X 1O~-5 n cm 2 for alloying at 3OO·C for 15 min. Auger electron spectroscopy depth profiles and Rutherford backscattering spectroscopy analysis for samples annealed at different temperatures show the diffusion of Au into GaSb and also give evidence of Ga outdiffusion and Zn in-diffusion. The presence of oxygen in the film surface and at the interface is discussed.

Interaction of Au with GaSb and its Impact on the Formation of Ohmic Contacts

“…Due to their small band gap, they are a natural material of choice for many applications in the infrared, while the small effective masses of light holes and conduction electrons, unique band offsets and surface properties makes them particularly challenging candidates for novel quantum-effect devices. However, few studies have been published on ohmic contacts to these materials [1,2]. The obtained results show that low Schottky barrier heights for metals on GaSb do not (419) favor significantly lower contact resistances.…”

The physics and technology of gallium antimonide: An emerging optoelectronic material

“…GaAsSb has been shown to facilitate p-type ohmic contacts to p -n -p AlGaAs/GaAs HBTs with specific contact resistivity as low as 5ϫ10 Ϫ7 ⍀ cm 2 . 281 A prototype n -p -n AlGaAs/GaAsSb/GaAs DHBT exhibited a stable current gain of 5 and a significant collector current density of 5ϫ10 4 A/cm 2 . GaSb p-channel modulation-doped FETs ͑MODFETs͒ with AlSb 0.9 As 0.1 /AlSb barrier layers have been studied by Luo and co-workers.…”

“…Ohmic contacts to p-GaSb doped in the range of 8 ϫ10 16 Ϫ1ϫ10 19 cm Ϫ3 are provided by thermal evaporation of several metals and alloys of Au, Ag and In after annealing in the range of 250-350°C for 10-30 min. [280][281][282] The specific contact resistivity c varies in the range of 10 Ϫ4 - 283 fabricated metal contacts of Cr/Au, Ti/Pt/Au and Au on p-GaSb by MBE. For Au contacts, c in the range of 1.4-7.8ϫ10 Ϫ8 ⍀ cm 2 have been obtained which are the lowest values ever reported so far for p-GaSb.…”

Front contact to the GaSb-photovoltaic converter: Properties and thermal stability

“…In paper [14] gold-based contacts Au (100 Å)-Zn (100 Å)-Au (800 Å) were deposited and the values of specific contact resistances were measured depending on annealing temperature in the atmosphere 92% N 2 + 8% H 2 . The minimum values of ρ c ∼ 1 • 10 −5 ohms • cm 2 were reached at T = 300 • C and annealing time 15 min.…”