Specific Process Knowledge/Etch/III-V RIE

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III-V RIE Plassys

Name: MG300 RIE
Vendor: Plassys

General information

III-V RIE is located in room A-1

Dry etching of III-V compound semiconductors is performed with a conventional Reactive Ion Etch (RIE) located in cleanroom A-1. The III-V RIE is a Plassys model MG300. Find the company website her: Plassys.

The system is equipped with a laser interferometer to monitor etch-rate and -depth.

The user manuals, user APVs, technical information and contact information can be found in LabManager:

III-V RIE (Plassys)

The diameter of the quartz plate is 20 cm, ie up to 2 4" wafers, 3 3" wafers or 4 2" wafers can be processed simultaneously. The area, A, of the quartz plate is 314 cm².

The intensity of the plasma is the ratio of power applied to the plasma, P, to the area, A, of the quartz plate. A power of 1000 W thus gives a plasma intensity of 0.32 W/cm². To strike a plasma, the applied power should be 50 W or more; if a process needs a lower power during etch it is necessary to initially strike the plasma with eg 50 W (higher powers are needed for lower gas pressures) for 5-10 sec where after the power can be lowered to the desired value.

The chamber should be cleaned after all usage of the machine; read more under Chamber Cleaning.

Process information

• CHF₃/O₂ RIE - SiO₂ and Si₃Ni₄ etch

• CH₄/H₂ RIE - InP and InGaAs(P) etch

• BCB polymer RIE - BCB polymer and resist etch

• Chamber Cleaning - Chamber cleaning

Overview of the performance of the RIE´s and some process-related parameters

Purpose	Dry etch of	SiO2 Si3N4 BCB Resist InP InGaAs
Performance (see specific recipes)	Etch rates	SiO2: ~1-30 nm/min Si3N4: ~17-38 nm/min BCB: ~70-880 nm/min (needs testing) Resist: ~30-98 nm/min (AZ5206 and ZEP520A), ~70-815 nm/min (AZ5214) InP: ~29 nm/min GaAs: ~9 nm/min
	Anisotropy	Can vary from isotropic to anisotropic with vertical sidewalls and on to a physical etch were the sidewalls are angled but without etching under the mask.
Process parameters	Plasma pressure	down to 10 mTorr
	Maximum Gas flows	O2: 50 sccm CHF3: 17.5 sccm CH4: 10 sccm H2: 50 sccm Ar: 20 sccm
Substrates	diameter of quartz plate	20 cm
	Substrate material allowed	III-V compound semiconductors
	Possible masking material	Photoresist/e-beam resist Titanium