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The inverted-gate colossal magnetoresistance-field-effect-transistors (CMR-FETs) were designed and successfully fabricated on the Si substrate by using semiconductor techniques. The studies on the capacitance properties were carried out under different temperatures, different frequencies, and different gate biases. The results indicate that La_0.8Ca_0.2MnO₃ is the typical p-type semiconductor. It was shown that the capacitance increases with the increasing of the temperature under certain gate bias. The sudden increase of the capacitance at 160 K was observed and needeed to be studied further. Meanwhile the capacitance decreased as the frequency increased with first order exponential decay fitting.

BST ceramics with doping of 1, 3, and 5 wt.% ZnBO were prepared by the conventional mixed oxide method and sintered at 1100°. X-ray diffraction analyses were carried out to verify the structural properties. 1, 3, and 5 wt.% ZnBO doped BST ceramics were crystallized with weak tetragonal structure at 1100°C. The grain growth behavior and shapes were investigated by scanning electron microscopy images. The electrical properties of 1, 3, and 5 wt.% ZnBO doped BST ceramics were investigated by impedance spectroscopy at the different temperatures (350, 375, and 400°C). Impedance spectroscopy data presented in Nyquist plot show the existence of both grain and grain boundary effects in all specimens. 1, 3, and 5 wt.% ZnBO doped BST ceramics showed negative temperature coefficient of resistance (NTCR). Also, the capacitances and resistances of grains and grain boundaries for 1, 3, and 5 wt.% doped BST ceramics were simulated through equivalent circuit with the parallelly connected capacitors and resistors. The capacitance and resistance were decreased when temperature and ZnBO dopants were increased.

Tailoring pore-creating method to fit the various demands of different researchers is the frontier issue in the research of electrode capacitance of boron-doped diamond (BDD). Two critical factors in achieving the desired capacitance are the pore size and shape. This work compares the characteristics and applicability of various pore-creating methods, and reveals the influence mechanism of factors such as surface area, size and shape of the pore, on the capacitance of BDD electrodes. Obtained results could facilitate researchers to develop a personalized pore-creating method to achieve the desired capacitance.