The temperature dependence of current-voltage (I-V ) and capacitance-voltage (C-V ) characteristics of the Au/n-InP Schottky barrier diodes has been measured in the temperature range of 80-320 K. The forward I-V characteristics are analysed on the basis of standard thermionic emission (TE) theory and the assumption of a Gaussian distribution of the barrier heights (BHs). It has been shown that the ideality factor decreases while the barrier height increases with increasing temperatures, on the basis of TE theory. Furthermore, the homogeneous BH value of approximately 0.524 eV for the device has been obtained from the linear relationship between the temperature-dependent experimentally effective BHs and ideality factors. The modified Richardson plot, according to inhomogeneity of the BHs, has a good linearity over the temperature range. The value of Richardson constant A * has been found to be 5.97 A cm −2 K −2 , which is close to the theoretical value of 9.4 A cm −2 K −2 for n-InP. Moreover, the temperature coefficient of the BH is found to be −3.16 × 10 −4 eV K −1 for Au/n-InP.

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We have identically prepared as many as 60 Ti/p-Si (100) Schottky barrier diodes (SBDs) with a doping density of about 10 15 cm −3 . The Si (100)-H surfaces were obtained by wet chemical etching in diluted hydrofloric acid. We have made a statistical study related to the experimental barrier heights (BHs) and ideality factors of the diodes, and we have looked at linear relationship between BHs and ideality factors. The BHs obtained from the current-voltage (I-V) characteristics varied from 0.556 to 0.617 eV, and the ideality factor varied from 1.019 to 1.196. The experimental BH and ideality factor distributions obtained from the I-V characteristics were fitted by a Gaussian function, and their mean values were found to be 0.577 ± 0.013 eV and 1.098 ± 0.044, respectively. Furthermore, the homogeneous BH value of approximately 0.602 eV for the device was obtained from the linear relationship between experimental effective BHs and ideality factors.

An experimental explanation of the forward bias Capacitance-frequency plots for intimate or MIS SBDs with perfect or imperfect ohmic back-contact has been made. It has been shown that there is no excess capacitance that could be ascribed to the interface states or minority carrier at the intimate SBDs (that is, without interfacial layer) with the perfect ohmic back contact (low-resistance). It has been found that the excess capacitance is only measurable at SBDs with imperfect back contacts or with an interfacial layer which separates the interface states from the metal. It has been found that excess capacitance can be generated by varying the resistance or quality of the back-ohmic contact to the bulk semiconductor substrate, that is, the density of minority carriers that are injected by the Schottky contact depends sensitively on the properties of the ohmic back-contact. Again, it has been seen that the excess capacitance has appeared owing to the interface states plus minority carriers in MIS SBDs with imperfect back contacts. Thus, it has been concluded that the excess capacitance at nonideal Schottky contacts has been caused not only by the interface states but also by the minority carriers or by the interface states plus minority carriers due to the poor frontside or poor backside contacts. Thereby, it has been experimentally shown that every forward bias C-f plots with excess capacitance cannot be used to extract the results related to the interface states.

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A study on parameters of the Sn/n-GaAs Schottky barrier diode (SBD) fabricated on an n-type GaAs substrate has been made. The Sn/n-GaAs SBD has shown a nearly ideal behaviour with ideality factor and barrier height (BH) values of 1.081 and 0.642 eV, respectively, from the experimental forward-bias current-voltage (I-V) characteristics. A BH value of 0.724 eV has been obtained from the experimental reverse-bias capacitance-voltage (C-V) characteristics. An accurate theoretical modelling of the effect of the presence of inhomogeneities on the electron transport across the metal-semiconductor interface has been applied. This model attempts to explain abnormal experimental results obtained on 'real' Schottky diodes. Our results clearly demonstrate that the electron transport at the metal-semiconductor interface is significantly affected by low-barrier regions (patches). When the experimental data are described by the thermionic emission theory of inhomogeneous Schottky contacts, it has been concluded that both the experimental forward and reverse I-V characteristics and the difference between the values of the experimental I-V and C-V SBHs should be considered. An experimental BH difference of = 0.082 V has been obtained for the Sn/n-GaAs SBD that is less than the critical value; therefore, it has been seen that the potential in front of the patch is not pinched off.