In this work, the interfacial electronic property between N-type LaAlO3/TiO2-SrTiO3 has been investigated by using scanning tunneling microscopy and spectroscopy (STM/S). With the consideration of the tip-induced band bending effect during STM measurements and in conjunction with the three-dimensional theoretically analysis, the schematic band structure of the hetero-structured SrTiO3/LaAlO3 is also revealed. Results indicate that the magnitude of the built-in field on the LaAlO3 is (30¡Ó5) mV/Å. The band bending on SrTiO3 side at the heterointerface is also observed. The band downshift of SrTiO3 side at the interface is 0.31 eV with about 0.8 nm decay length.

No description available.

Organic transistors with vertical current transport like the Permeable Base Transistor (PBT) show a high performance while allowing for an easy fabrication on the device level. For a simple implementation on a circuit level, ambipolar transistors, providing the functionality of n-type as well as p-type devices, have a benefit for complementary logic. This requires transistors where electrons and holes are present. Here, we investigate a potential concept of bipolar current transport in PBTs. In our device structure, we use the base electrode to control the current flow, but also to investigate the charge carrier transport. The ambipolar organic PBT achieves a charge carrier transmission of 88% and a current density above 200mA=cm². Additionally, we show that recombination near the base is required in an ambipolar PBT for a good performance.