Defect Modulation Doping

Abstract

The doping of semiconductor materials is a fundamental part of modern technology, but the classical approaches have in many cases reached their limits both in regard to achievable charge carrier density as well as mobility. Modulation doping, a mechanism that exploits the energy band alignment at an interface between two materials to induce free charge carriers in one of them, is shown to circumvent the mobility restriction. Due to an alignment of doping limits by intrinsic defects, however, the carrier density limit cannot be lifted using this approach. Here, a novel doping strategy using defects in a wide bandgap material to dope the surface of a second semiconductor layer of dissimilar nature is presented. It is shown that by depositing an insulator on a semiconductor material, the conductivity of the layer stack can be increased by 7 orders of magnitude, without the necessity of high-temperature processes or epitaxial growth. This approach has the potential to circumvent limits to both carrier mobility and density, opening up new possibilities in semiconductor device fabrication, particularly for the emerging field of oxide thin film electronics.

Electrical Properties of Low-Temperature Processed Sn-Doped In2O3 Thin Films: The Role of Microstructure and Oxygen Content and the Potential of Defect Modulation Doping

“…The results provide guidelines for low-temperature processing of doped In2O3 films and will be used to explain the effects of Al2O3 deposition on the electrical properties of ITO and the conditions for realizing defect modulation doping of this compound. Defect modulation doping utilizes a Fermi level in a contact phase, which is pinned by defects at a high energy [31]. Carrier concentrations near an interface, which are higher than those observed by conventional doping, can be achieved by this technique.…”

Inorganic thermoelectric materials: A review

“…Nevertheless, a heavily doped material enhances n between 10 19 ‐10 21 cm −3 , while it reduces μ of charge carriers due to enhanced ionized impurity scattering . In order for a trade‐off between n and μ , modulation doping has been recently used to discretize the charge carriers from ionized dopants to reduce ionized impurity scattering for high μ , while enhanced n in TE materials . Figure shows the modulation doping of semiconductors and their energy diagram for n‐ and p ‐type doping.…”

Spin Coating Method Fabricated of In2O3 Thin Films

“…DOI: 10.2478/awutp-2019-0005 on it is a class of good vector of the semiconductor materials due to the n-types in nature [4].…”

“…The optical band gap of In 2 O 3 thin films was located in the range of 3.5 -4 eV, which is varied by various conditions like deposition method, precursor molarity, substrate temperature, film thickness, crystallization temperature and doping level [1][2][3][4][5].…”

“…In 2 O 3 thin films can be fabricated by several techniques such as electrochemical deposition, pulsed laser deposition (PLD), magnetron sputtering technique, molecular beam epitaxy (MBE), reactive evaporation, sol-gel process, chemical vapor deposition, and spray pyrolysis [1][2][3][4][5]. spectrophotometer (LAMBDA 25) in the range of 300-1000 nm.…”