Limits...
Evaluation of intrinsic charge carrier transport at insulator-semiconductor interfaces probed by a non-contact microwave-based technique.

Honsho Y, Miyakai T, Sakurai T, Saeki A, Seki S - Sci Rep (2013)

Bottom Line: We have successfully designed the geometry of the microwave cavity and the thin metal electrode, achieving resonance of the microwave cavity with the metal-insulator-semiconductor (MIS) device structure.By means of the present measurement system named field-induced time-resolved microwave conductivity (FI-TRMC), the pentacene thin film in the MIS device allowed the evaluation of the hole and electron mobility at the insulator-semiconductor interface of 6.3 and 0.34 cm² V⁻¹ s⁻¹, respectively.This is the first report on the direct, intrinsic, non-contact measurement of charge carrier mobility at interfaces that has been fully experimentally verified.

View Article: PubMed Central - PubMed

Affiliation: Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.

ABSTRACT
We have successfully designed the geometry of the microwave cavity and the thin metal electrode, achieving resonance of the microwave cavity with the metal-insulator-semiconductor (MIS) device structure. This very simple MIS device operates in the cavity, where charge carriers are injected quantitatively by an applied bias at the insulator-semiconductor interface. The local motion of the charge carriers was clearly probed through the applied external microwave field, also giving the quantitative responses to the injected charge carrier density and charge/discharge characteristics. By means of the present measurement system named field-induced time-resolved microwave conductivity (FI-TRMC), the pentacene thin film in the MIS device allowed the evaluation of the hole and electron mobility at the insulator-semiconductor interface of 6.3 and 0.34 cm² V⁻¹ s⁻¹, respectively. This is the first report on the direct, intrinsic, non-contact measurement of charge carrier mobility at interfaces that has been fully experimentally verified.

No MeSH data available.


Correlation between charge carrier number ΔN and pseudo electrical conductivity ΔNμ.Red and blue circles indicate holes and electrons, respectively. The slopes of the fitted curves correspond to the value of the mobility μ.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3822380&req=5

f6: Correlation between charge carrier number ΔN and pseudo electrical conductivity ΔNμ.Red and blue circles indicate holes and electrons, respectively. The slopes of the fitted curves correspond to the value of the mobility μ.

Mentions: When a gate bias of –40 V was applied, the pentacene/PMMA MIS device displayed a time-dependent microwave power change (ΔPr) with saturated behavior (Fig. 5a), where the bias voltage was applied between 9 to 39 ms. At the same time, the charging-discharging current appeared to respond to the applied gate bias (Fig. 5a). The differential of ΔPr was in good agreement with the current signal, which indicates that the ΔPr response is associated clearly with charges accumulated in the MIS device. The ΔPr response resembles the voltage response characteristics of a capacitor in a typical resistor–capacitor (RC) circuit, and in the decay region (39–50 ms) gives the linear plots shown in Fig. S5. Fig. 5b. shows the dependence of ΔPr on the applied gate bias. When the applied gate bias voltage was decreased from 0 V to –60 V, ΔPr increased proportionally, probably because the number of accumulated holes became large in relation to the absolute value of the gate bias. In sharp contrast, the response of ΔPr to the positive gate bias was poor from 0 V to 60 V (Fig. 5c), suggesting a lower conductivity for electrons in the MIS device. After measuring ΔPr at each gate bias and capacitance, and using equations (5) and (1), we can draw the ΔN–ΔNμ plots, as shown in Fig. 6. The slope ( = δNμ/δN) corresponds to the value of the charge carrier mobility, providing the approximate values μhole = 6.3 cm2 V−1 s−1 and μelectron = 0.34 cm2 V−1 s−1 for the pentacene MIS device.


Evaluation of intrinsic charge carrier transport at insulator-semiconductor interfaces probed by a non-contact microwave-based technique.

Honsho Y, Miyakai T, Sakurai T, Saeki A, Seki S - Sci Rep (2013)

Correlation between charge carrier number ΔN and pseudo electrical conductivity ΔNμ.Red and blue circles indicate holes and electrons, respectively. The slopes of the fitted curves correspond to the value of the mobility μ.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3822380&req=5

f6: Correlation between charge carrier number ΔN and pseudo electrical conductivity ΔNμ.Red and blue circles indicate holes and electrons, respectively. The slopes of the fitted curves correspond to the value of the mobility μ.
Mentions: When a gate bias of –40 V was applied, the pentacene/PMMA MIS device displayed a time-dependent microwave power change (ΔPr) with saturated behavior (Fig. 5a), where the bias voltage was applied between 9 to 39 ms. At the same time, the charging-discharging current appeared to respond to the applied gate bias (Fig. 5a). The differential of ΔPr was in good agreement with the current signal, which indicates that the ΔPr response is associated clearly with charges accumulated in the MIS device. The ΔPr response resembles the voltage response characteristics of a capacitor in a typical resistor–capacitor (RC) circuit, and in the decay region (39–50 ms) gives the linear plots shown in Fig. S5. Fig. 5b. shows the dependence of ΔPr on the applied gate bias. When the applied gate bias voltage was decreased from 0 V to –60 V, ΔPr increased proportionally, probably because the number of accumulated holes became large in relation to the absolute value of the gate bias. In sharp contrast, the response of ΔPr to the positive gate bias was poor from 0 V to 60 V (Fig. 5c), suggesting a lower conductivity for electrons in the MIS device. After measuring ΔPr at each gate bias and capacitance, and using equations (5) and (1), we can draw the ΔN–ΔNμ plots, as shown in Fig. 6. The slope ( = δNμ/δN) corresponds to the value of the charge carrier mobility, providing the approximate values μhole = 6.3 cm2 V−1 s−1 and μelectron = 0.34 cm2 V−1 s−1 for the pentacene MIS device.

Bottom Line: We have successfully designed the geometry of the microwave cavity and the thin metal electrode, achieving resonance of the microwave cavity with the metal-insulator-semiconductor (MIS) device structure.By means of the present measurement system named field-induced time-resolved microwave conductivity (FI-TRMC), the pentacene thin film in the MIS device allowed the evaluation of the hole and electron mobility at the insulator-semiconductor interface of 6.3 and 0.34 cm² V⁻¹ s⁻¹, respectively.This is the first report on the direct, intrinsic, non-contact measurement of charge carrier mobility at interfaces that has been fully experimentally verified.

View Article: PubMed Central - PubMed

Affiliation: Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.

ABSTRACT
We have successfully designed the geometry of the microwave cavity and the thin metal electrode, achieving resonance of the microwave cavity with the metal-insulator-semiconductor (MIS) device structure. This very simple MIS device operates in the cavity, where charge carriers are injected quantitatively by an applied bias at the insulator-semiconductor interface. The local motion of the charge carriers was clearly probed through the applied external microwave field, also giving the quantitative responses to the injected charge carrier density and charge/discharge characteristics. By means of the present measurement system named field-induced time-resolved microwave conductivity (FI-TRMC), the pentacene thin film in the MIS device allowed the evaluation of the hole and electron mobility at the insulator-semiconductor interface of 6.3 and 0.34 cm² V⁻¹ s⁻¹, respectively. This is the first report on the direct, intrinsic, non-contact measurement of charge carrier mobility at interfaces that has been fully experimentally verified.

No MeSH data available.