M. H. Jeon

Temperature-dependent Cl2/Ar plasma etching of bulk single-crystal ZnO

The etch rate of bulk ZnO in Cl2/Ar high density plasmas was found to be thermally activated with an activation energy of ∼0.31 eV at 200 °C).

Role of inert gas additive on dry etch patterning of InGaP in planar inductively coupled BCl3 plasmas

Abstract The dry etch characteristics of InGaP in BCl3 planar inductively coupled plasmas (ICP) with additions of Ar or Ne were determined. The inert gas additive provided enhanced etch rates relative to pure BCl3 and Ne addition in particular produced much higher etch rates at low ratios of BCl3 in the mixture. The etched features tended to have sloped sidewalls and much rougher surfaces than for GaAs and AlGaAs etched under the same conditions. The practical effect of the Ar or Ne addition was the ability to operate the ICP source over a somewhat broader range of pressures and still maintain practical etch rates. The use of room temperature BCl3-based etching in a planar ICP appears feasible for base and emitter mesa applications in InGaP/GaAs heterojunction bipolar transistors.

Planar Inductively Coupled BCl3 Plasma Etching of III-V Semiconductors

Both Ga-based (GaAs, AlGaAs) and In-based (InGaP, InP, InAs, and InGaAsP) compound semiconductors were etched in a planar inductively coupled plasma (ICP) reactor in pure BCl 3 . The Ga-based materials etched at significantly higher rates, as expected from the higher volatilities of their trichloride etch products relative to InCl 3 . In contrast to the more common cylindrical geometry ICP sources, the dc self-bias which controls ion energy is not strongly dependent on source power up to ∼400 W while etch rates increase rapidly over this power range. The source tunes easily even at very low powers (<100 W) but operates inefficiently above ∼10 mTorr, with a marked decrease in both emission intensity from the discharge and in resulting etch rates of the compound semiconductors. The etched surfaces of both AlGaAs and GaAs have comparable root-mean-square roughness and similar stoichiometry to the unetched control samples, while the surfaces of In-based materials are degraded by the BCl 3 etching.

High Density Inductively Coupled Plasma Etching of InP in BCl 3 -Based Chemistries

We studied InP etching in high density planar inductively coupled and /Ar plasmas(PICP). The investigated process parameters were PICP source power, RIE chuck power, chamber pressure and /Ar gas composition. It was found that increase of PICP source power and RIE chuck power increased etch rate of InP, while that of chamber pressure decreased etch rate. Etched InP surface was clean and smooth (RMS roughness /min) after the planar /Ar ICP etching. It may make it possible to open a new regime of InP etching with -free plasma chemistry. Some amount of Ar addition (

Dry Etching of GaAs and AlGaAs Semiconductor Materials in High Density BCl 3 and BCl 3 /Ar Inductively Coupled Plasmas

We investigated dry etching of GaAs and AiGaAs in a high density planar inductively coupled plasma system with BCland BCl/Ar gas chemistry. A detailed etch process study of GaAs and ALGaAs was peformed as functions of ICP source power, RIE chuck power and mixing ratio of and Ar. Chamber process pressure was fixed at 7.5 mTorr in this study. The ICP source power and RIE chuck power were varied from 0 to 500 W and from 0 to 150 W, respectively. GaAs etch rate increased with the increase of ICP source power and RIE chuck power. It was also found that etch rates of GaAs in /5Ar plasmas were relatively high with applied RIE chuck power compared to pure 20 sccm plasmas. The result was the same as AlGaAs. We expect that high ion-assisted effect in /Ar plasma increased etch rates of both materials. The GaAs and AlGaAs features etched at 20 sccm and /5Ar with 300 W ICP source power, 100 W RIE chuck power and 7.5 mTorr showed very smooth surfaces(RMS roughness