Electrical characterization of Fe-doped semi-insulating InP grown by metalorganic chemical vapor deposition

Abstract

The bulk resistivity of Fe-doped metalorganic chemical vapor deposited grown epitaxial InP was determined from current-voltage and capacitance measurements made on Schottky-diode-like devices. The current-voltage data exhibit both an ohmic and a space-charge-limited regime, and the capacitance was found to be independent of applied bias. The electrical thickness was obtained from the capacitance using a relationship appropriate for current injection. Data for two samples representing both thin (∼1 μm) and thick (∼9 μm) epitaxial layers are presented. The resistivities were 6.5×107 Ω cm and 2.2×108 Ω cm.

Combined Macro/Nanoscale Investigation of the Chemical Vapor Deposition of Fe from Fe(CO)5

“…Following the trend of Fe(CO) 5 decarbonylation for these two temperatures, the Fe(CO) 5 available for the surface reaction decreases at T s = 223 °C. On the other hand, Fe(CO) 3 increases with the increased decomposition of Fe(CO) 5 . This trend is reinforced in the vicinity of the susceptor where the temperature is higher (see also Figure 4a,b, left) and eventually, this combination leads to the decrease of the deposition rate.…”

“…Interestingly enough, the rate of recombination of Fe(CO) 2 with CO (green lines) is almost the same as the decomposition rate of Fe(CO) 3 (blue lines). As a result, the Fe(CO) 2 decomposition (Table 1, G4) and consequently the FeCO decomposition (Table 2, SR3) do not occur, since all Fe(CO) 2 intermediates are consumed in the recombination with CO to form Fe(CO) 3 . The recombination of Fe(CO) 4 with CO yields null rates, consistent to literature reports, [17] whereas the recombination of Fe(CO) 3 with CO occurs at negligible rates (≈10 −9 kmol m −3 s −1 ), due to the consumption of the tricarbonyl by the surface reaction (Table 2, SR2).…”

“…As a result, the Fe(CO) 2 decomposition (Table 1, G4) and consequently the FeCO decomposition (Table 2, SR3) do not occur, since all Fe(CO) 2 intermediates are consumed in the recombination with CO to form Fe(CO) 3 . The recombination of Fe(CO) 4 with CO yields null rates, consistent to literature reports, [17] whereas the recombination of Fe(CO) 3 with CO occurs at negligible rates (≈10 −9 kmol m −3 s −1 ), due to the consumption of the tricarbonyl by the surface reaction (Table 2, SR2). Figure 3c shows the mass fractions of Fe(CO) 5 and Fe(CO) 3 at T s = 223 °C (black and red solid lines, respectively) and T s = 215 °C (black and red dashed lines, respectively), still 1 mm above the susceptor.…”

“…As shown in Figure 3d, the CO mass fraction is higher at T s = 223 °C contributing to a higher inhibition of the surface processes by CO (Equation (3)) and subsequently to the decrease of the deposition rate. Thus, the model validates the two main reasons for the reduction of the deposition rate at high temperatures that is, increased decomposition rate of the precursor and poisoning of the surface by CO. [19,21] Figure 4 shows the temperature (left) and the gas velocity profiles (right) at T s = 223 °C (Figure 4a 3 (red lines) at T s = 223 (solid lines) and 215 °C (dashed lines). d) The mass fraction of CO at T s = 223 (solid line) and 215 °C (dashed line).…”

“…[1] They can also be applied as components in magnetic metal multilayers [1] and in metallic alloys, such as NiFe, FeMn, FePt, and NdFeB to provide advanced materials with high quality magnetic properties [2] or as dopants to form semi-insulating InP layers. [3] It was shown recently that the bulk Al 13 Fe 4 intermetallic alloy presents excellent catalytic activity which may be further improved if processed in the form of thin films. [4] Several methods have been developed for the production of Fe and Fe-containing thin films, among which chemical vapor deposition (CVD) that combines high deposition rates, moderate process temperatures, reduced effluents volume, and conformal coverage of complex surfaces.…”