Inductively coupled plasma etching of III–V antimonides in BCl3/Ar and Cl2/Ar

Abstract

Articles you may be interested inInductively coupled plasma etching of through-cell vias in III-V multijunction solar cells using SiCl4/Ar J. Vac. Sci. Technol. B 31, 06FF05 (2013); 10.1116/1.4822015Detailed analysis of the influence of an inductively coupled plasma reactive-ion etching process on the hole depth and shape of photonic crystals in In P ∕ In Ga As P Low damage dry etching of III-V materials for heterojunction bipolar transistor applications using a chlorinated inductively coupled plasma Inductively coupled plasma ͑ICP͒ etching characteristics of GaSb and AlGaAsSb have been investigated in BCl 3 /Ar and Cl 2 /Ar plasmas. The etch rates and selectivity between GaSb and AlGaAsSb are reported as functions of plasma chemistry, ICP power, rf self-bias, and chamber pressure. It is found that physical sputtering desorption of the etch products plays a dominant role in BCl 3 /Ar ICP etching, while in Cl 2 /Ar plasma, the chemical reaction dominates the etching. GaSb etch rates exceeding 2 m/min are achieved in Cl 2 /Ar plasmas with smooth surfaces and anisotropic profiles. In BCl 3 /Ar plasmas, etch rates of 5100 and 4200 Å/min are obtained for GaSb and AlGaAsSb, respectively. The surfaces of both GaSb and AlGaAsSb etched in BCl 3 /Ar plasmas remain smooth and stoichiometric over the entire range of plasma conditions investigated. This result is attributed to effective removal of etch products by physical sputtering. For a wide range of plasma conditions, the selectivity between GaSb and AlGaAsSb is close to unity, which is desirable for fabricating etched mirrors and gratings for Sb-based midinfrared laser diodes.

HgCdTe focal plane arrays for dual-color mid- and long-wavelength infrared detection

“…15 The ICP technique has been identified in the semiconductor industry as a more attractive choice for manufacturing applications because of easier scale up to larger wafer sizes and greater automation capability than ECR. 16,17 Consequently, ICP tools that deliver high plasma uniformity over large wafer sizes are seeing widespread application in silicon and III-V semiconductor technology. 15 Work performed at RVS on HgCdTe HDP mesa etching with ECR and ICP techniques has identified ICP etching capable of producing up to a factor of 5 reduction in lateral mask erosion during etching, improved etch-depth uniformity, and less significant etch-lag effects.…”

Inductively coupled plasma etching of III–V antimonides in BCl3/SiCl4 etch chemistry

“…There is also a possibility of undercutting when operated at high Cl 2 concentration or chamber pressure, since the chemical reaction dominated process results in lateral etching. The BCl 3 /Ar mixture [5,6] usually produces much smoother surfaces with vertical sidewalls, an important benefit of BCl 3 , but the etch rates are considerably lower due to the limited number of reactive Cl in BCl 3 /Ar plasma compared to Cl 2 /Ar plasma.…”

“…The most common recipes include Cl 2 /Ar and BCl 3 /Ar, where the inert gas Ar helps enhance the efficiency of etch product desorption by ion bombardment. The Cl 2 /Ar recipes [5] typically produce high etch rates, but result in rougher surfaces. There is also a possibility of undercutting when operated at high Cl 2 concentration or chamber pressure, since the chemical reaction dominated process results in lateral etching.…”

Fabrication of Sub-25 nm Diameter GaSb Nanopillar Arrays by Nanoscale Self-Mask Effect

“…32,38 Specifically, in Figure 6a and b, heights of nanopillars were found to increase from 264 ± 23 nm to 1206 ± 110 nm. The result of longer nanopillars can be attributed to the decreasing oxide removal rate on top of nanopillars resulting from the reduced sputter etching.…”