With the complementary metal oxide semiconductor (CMOS) field-effect transistor circuits approaching their physical limits, the search for next generation nanoelectronic devices becomes more and more urgent. Very recently, three-terminal ballistic junctions (TBJs) [1-4] and planar quantum wire transistors (QWTs) [5] are successfully fabricated on III-V heterostructures. Room temperature measurements reveal various novel electrical properties [1-5].
In this work, we report on the realization of novel nanoelectronic analogue and digital circuits with TBJs and QWTs made from InP/In0.75Ga0.25As heterostructure. First we show that a single TBJ can function as a frequency mixer or phase detector. When two AC signals of frequencies, f1 and f2, are sent into the two branches of the TBJ, the measured output signal from the third branch contains both the sum and the difference frequency components, f1¡Àf2. In the special case where f1=f2, the DC output at the third branch can be used to determine the phase difference of the two input signals. Second, we fabricate an integrated nanostructure which contains two planar QWTs. The circuit can be used as an RS flip-flop element. The measured results coincide very well with the truth table of RS flip-flop circuits, and the signal gain of as large as 4 (defined by the ratio between the output and input logic swing) has been achieved. Third, we make an even more complex nanoelectronic circuit by integration of two TBJs, two QWTs, and two additional side gates. This integrated nanoelectronic circuit shows the RS flip-flop functionality with large noise margins in both high and low logic level inputs.
All the above devices operate at room temperature. These devices also have advantages over traditional circuits in terms of small size and reduced circuit complexity. Therefore, TBJs and QWTs could be used as new building blocks in nanoelectronics.
[1] I. Shorubalko and H.Q. Xu et al., Appl. Phys. Lett. 79 (2001) 1384.
[2] I. Shorubalko and H.Q. Xu et al., IEEE Electron Device Lett. 23 (2002) 377.
[3] H.Q. Xu et al., IEEE Electron Device Lett. 25 (2004) 164.
[4] D. Wallin et al., Appl. Phys. Lett. 89 (2006) 092124.
[5] S. Reitzenstein et al., IEEE Electron Device Lett. 26 (2005) 142.
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