Fabrication and characterization of Algan/Gan high electron mobility transistors on silicon

Abstract

"Moore's Law" states that the number of transistors in an integrated circuit will double approximately every two years. True to this observation, the number of transistors per Si IC indeed has doubled every 18 months since the 1970s. In accordance with the scaling trend predicted in Moore's Law, not only is the packing density of transistors increased but devices' performance are significantly improved as well. However as the size of transistors continuously shrinks, several issues such as the fundamental limitation of Si, quantum

A Review on Gallium Nitride for Liquid Sensors: Fabrications to Applications

“…Unlike most III−V semiconductors (e.g., GaAs) with a zincblende crystal structure, GaN structure is a tetrahedrally coordinated wurtzite structure with a lack of inversion symmetry along the c-axis. 60 This lack of symmetry along the c-axis provides spontaneous polarizations. 61 The variation in the lattice constant between the AlN and GaN results in a significant lattice mismatch when growing AlGaN on GaN.…”

“…The bandgap difference between both semiconductors leads to band bending, causing the formation of a two-dimensional electron channel in the upper section of the GaN layer. Unlike most III–V semiconductors (e.g., GaAs) with a zincblende crystal structure, GaN structure is a tetrahedrally coordinated wurtzite structure with a lack of inversion symmetry along the c -axis . This lack of symmetry along the c -axis provides spontaneous polarizations .…”

AlGaN/GaN high electron mobility transistor for various sensing applications: A review

“…The wet chemical etching is not feasible due to the strong bond energy of GaN besides a very slow etch rate and proper mask. The dry etch processes are widely used like reactive ion etching using inductively coupled plasma (RIE-ICP) with Ar/CH4/H2/Cl2 plasma and ion beam etching based on Ar+ ion sputtering [21] . Ion implantation techniques are also harnessed for mesa isolation where the incident ion energy and dosages can be optimized for a damage and disorder-free process schemes utilizing H + , He + , N + , F + , Mg + and Ar + /Kr + ions [43], [44].…”

“…The growth of ZnO nanorods increases surface to volume ratio so that improved catalytic activity occurs at surface and the subsequent reactions are given in Eq. ( 19), (20) and (21). The sensing region dimension was 50x50 µm 2 .…”