Etching

Wet etching

https://transene.com/etch-compatibility/ Data comparing different bottles of transene type D: Etching on Si, InAs (001), and GaAs(001)

Etch rate with MIF321

The Al/SiO2 chips are developed in MIF321 for 50 sec, before etching.

Time [seconds]	0	3	6	9	12	15
Δh [nm]	10	25	35	40	50	60

Etch rate with BHF

etching ALD HfOx

Blank Si samples with HfOx grown locally by ALD. The sample was etched for 2 mins and the film was measured by ellipsometry. Then, repeated the etch 3 times.

Time [minutes]	0	2	4	6
h [nm]	21.53	17.18	12.18	7.55

Dry etching

For dry etching, you can use AJA systems or Plassys Evaporator. AJA1 and Plassys have an Ion gun for DC Kaufman milling, and in AJA2 you can do RF milling.

Erch rate with AJA1

• Argon flow: 15 sccm.
• pressure: 1 mTorr.
• Angle: 90 degree tilt , i.e. head on.
• Milling duration: 2 minutes warm-up followed by 4 minutes milling.

Kaufmann settings

• cathode Amps = 7.0
• Discharge Volts = 40.0
• Discharge Amps = 0.5
• Beam Volts = 300.0
• beam Amps = 23.0
• Accelerator Volts = 120.0
• Accelerator Amps = 10.0
• Emission mAmps = 46.0
• Neutralizer Amps = 11.0

Gold

Time [minutes]	1	3	5	7
Δh [nm]	9.2	28.4	46.9	46.5

Aluminum

Time [minutes]	1	3	5	7
Δh [nm]	2.5	7.7	13.4	21.3

Erch rate with AJA2

SiOx

Milling of SiOx on Si for 5 minutes at different pressures

Power [W]	Δh [nm]
	6 mTorr	12 mTorr	18 mTorr	24 mTorr
50	2.7	3.0	5.5	3.7
100	9.8	13.6	10.4	17.3
150	13.5	16.2	47.3	35.1
200	24.3	35.9	57.0	53.1
250	38.3	47.9	77.3	72.7

Data from Shiv, qdevwiki Aug 2016