Memory device application of wide-channel in-plane gate transistors with type-II GaAsSb-capped InAs quantum dots

Abstract

We demonstrate room-temperature electron charging/discharging phenomena of InAs quantum dots using wide-channel in-plane gate transistors. The device based on type-II GaAsSb-capped InAs quantum dots exhibits both the longer charging and discharging times than those of the type-I counterpart with GaAs capping layers. The slow charge relaxation of GaAsSb-capped InAs quantum dots and simple architecture of in-plane gate transistors reveal the potential of this device architecture for practical memory applications. V

Charge character in the double‐barrier quantum dots in well hybrid structure

“…This phenomenon occurs at the bias of about −0.75 V. When the light intensity was enhanced, the hysteresis became more obvious. This fact implies that a noticeable amount of electrons has been transferred back and forth by up-sweeping bias and down-sweeping bias [15][16][17][18]. The transferred electrons are accumulated on the far left side of the X-valley QW of the AlAs layer, while the holes still remain in the Γ-valley GaAs QW.…”

“…Once the charge polarisation builds up, it should disappear at another bias in the backwards sweeping. Hence, both the space-charge effect and the transferred electrons in the X-valley QW of the AlAs layer, a hysteresis appeared in the measured C-V curves [15][16][17][18]. When the was light turned off, the hysteresis still existed.…”

“…The chopping frequency was 13 Hz, and the power intensity was The photocurrent transient from laser-off to laser-on reflects a fast generation process in which electrons and holes were excited and transferred so that they became separated in both real and K spaces. The decay transient of the photocurrent from laser-on to laser-off reveals the time that the carrier (electrons and holes) motion, which were stored in the X-valley QW of the AlAs layer and the Γ-valley GaAs-QW, respectively, to recombine either radiatively recombination or non-radiatively recombination [15][16][17][18]. Fig.…”

Long-Wavelength In-Plane Gate InAs Quantum-Dot Phototransistors

“…Due to the operation speed of the device is mainly limited by the migration speed of the mobile surface electrons, high-speed photodetector can be a promising application for IPGTs. By inserting a GaAsSbcapped InAs quantum-dot (QD) layer beneath the 2DEG channel, memory device application is also demonstrated with hysteresis observed in the I D −V GS curves under different bias sweeping directions [8]. By replacing the 2DEG channel with a single n-type doped GaAs layer, transistor behaviors can still be observed based on similar operation mechanisms [9].…”

Photonic switching devices based on semiconductor nano-structures

“…While a variety of QD-based photonic devices including lasers [31,32], optical amplifiers [33,34], optical memories [35,36] and switches [17,37] have been successfully demonstrated, their dense integration has been hindered by intrinsic material problems. The two most significant of these are: (1) the inhomogeneous broadening of optical spectra which is a natural consequence of self-assembly, (2) the small cross-section and short interaction length of QDs when interacting with light.…”