Ion Mill Rates

The table below lists the sputter yield data for Ar+ ions published by Nils Laegreid and G.K. Wehner in the 1961 manuscript "Sputtering Yields of Metals for Ar+ and Ne+ Ions with Energies from 50 to 600 eV". The data was acquired experimentally by immersing spherical targets in an Ar plasma and measuring mass loss. The actual yield may be 10% higher than reported due to uncertainties in measuring the ion current. Refer to the manuscript for details.

Target Yield [atoms/ion]
100 [eV] 200 [eV] 300 [eV] 600 [eV]
Ag 0.630 1.580 2.200 3.400
Al 0.110 0.350 0.650 1.240
Au 0.320 1.070 1.650 2.430 (500)
Be 0.074 0.180 0.290 0.800
Co 0.150 0.570 0.810 1.360
Cr 0.300 0.670 0.870 1.300
Cu 0.480 1.100 1.590 2.300
Fe 0.200 0.530 0.760 1.260
Ge 0.220 0.500 0.740 1.220
Hf 0.160 0.350 0.480 1.830
Ir 0.120 0.430 0.700 1.170
Mo 0.130 0.400 0.580 0.930
Nb 0.068 0.250 0.400 0.650
Ni 0.280 0.660 0.950 1.520
Os 0.057 0.360 0.560 0.950
Pd 0.420 1.000 1.410 2.390
Pt 0.200 0.630 0.950 1.560
Re 0.100 0.370 0.560 0.910
Rh 0.190 0.550 0.860 1.460
Ru 0.140 0.410 0.680 1.300
Si 0.070 0.180 0.310 0.530
Ta 0.100 0.280 0.410 0.620
Th 0.097 0.270 0.420 0.660
Ti 0.081 0.220 0.330 0.580
V 0.110 0.310 0.410 0.700
W 0.068 0.290 0.400 0.620
Zr 0.120 0.280 0.410 0.750
U 0.140 0.350 0.590 0.970

The table below lists the sputtering rate data for Ar+ ions for the previous list of materials. This dataset was published by Kaufman & Robinson, Inc in the book titled "Applications of Broad-Beam Ion Sources: An Introduction". The rates were calculated assuming a beam current density of 1 [mA/cm2] using the formula:
     R = 62.2Yw/ρ
where R is the etch rate in [Å/min], Y is the yield in [atoms/ion], w is the atomic weight in [amu] and ρ is the density in [g/cm3].

Target Rate [Å/min] for a current density of 1 [mA/cm2]
100 [eV] 200 [eV] 300 [eV] 600 [eV]
Ag 420 1100 1500 2400
Al 82 270 450 770
Au 170 710 1100 1900
Be 22 50 94 190
C 4 11 22 55
Co 82 260 380 620
Cr 150 330 440 650
Cu 250 530 750 1300
Fe 97 260 370 590
Ge 200 480 690 1000
Hf 46 130 190 360
Ir 71 260 400 680
Mo 64 240 360 590
Nb 37 160 280 480
Ni 130 300 440 740
Os 35 200 320 570
Pd 270 600 860 1400
Pt 110 390 580 970
Re 73 220 340 600
Rh 110 310 480 840
Ru 78 240 370 700
Si 41 160 260 420
Ta 56 200 310 460
Th 120 410 580 880
Ti 58 160 250 420
V 63 170 230 390
W 46 140 210 340
Zr 110 280 410 700
U 120 310 480 840