The downscaling of semiconductor devices, because of increasing the operating speed and decreasing power consumption, has mainly been responsible for the progress of integrated circuit (ICs). However, it is predicted that semiconductor fabrication tec...
The downscaling of semiconductor devices, because of increasing the operating speed and decreasing power consumption, has mainly been responsible for the progress of integrated circuit (ICs). However, it is predicted that semiconductor fabrication technology will reach the downscaling limit. Overcoming the downscaling limit requires a new paradigm in electronics. In the semiconductor electronics, electron charges play the key role while electron spin plays no role at all. An electronics based on the spin degrees of freedom of the electron represents a new paradigm, spin FET (field effect transistor) which will require a way of controlling electron spins in semiconductor channels by using the gate voltage. This structure was first elucidated by Datta and Das as the basic principle for the realization of a novel electronic device.
In this paper, we described the injection device of spin FET that uses a semiconductor two dimensional electron gas (2DEG) channel. This device basically consists of two ferromagnetic films (Ni_(81)Fe_(19)) of spin injector and detector, 2DEG channel of InAs HEMT. Especially, we have investigated to a new fabrication method about the device structure that is flatness of the shape of spin injector and detector on the channel by using vanadium material. Through this method, the spin injector and detector having nano-scaled length have shown to surprising effect of magnetic domains like single domain. For non-local geometry, △R of 4 mΩ is detected and for local spin valve geometry, magneto-resistance of 0.1 are obtained at T=10K. Due to sharp magnetic switching, the clear spin signal transition between parallel and anti-parallel alignment is observed. And, we have confirmed through theoretical calculation that the spin orbit interaction can be controlled by the gate voltage through our data of spin injection experiment, which is the important step towards the development of functional spin devices.