RESUMEN
This study employs quasiparticle-corrected DFT calculations to explore the electronic, optical, and surface adsorption properties of Li-doped hexagonal boron nitride (h-BNLi) monolayers. The results reveal that Li doping introduces two defect states into the wide band gap of the monolayer, reducing the band gap from 5.73 eV to 3.72 eV at the K-Γ point of the Brillouin zone. Using the GW approach to incorporate quasiparticle energies demonstrates a distinct advantage over conventional DFT, leading to qualitative shifts in band alignment across the Brillouin zone. Additionally, we identify intragap transitions driven by these defect states, resulting in a significant red shift in the optical gap, decreasing it from 5.73 eV to 1.61 eV in the doped monolayer. Moreover, Li doping enhances the detection of carbon-based gas molecules, raising the surface adsorption energy by -0.42 eV and -0.45 eV compared to the pristine monolayer. These findings hold substantial promise for the application of h-BNLi in electronic, optoelectronic, optical, and sensing devices, effectively subjugating the challenge posed by its wide band gap.
RESUMEN
Laser scanning optical beam induced current (OBIC) microscopy has become a powerful and nondestructive alternative to other complicated methods like electron beam induced current (EBIC) microscopy, for high resolution defect analysis of electronic devices. OBIC is based on the generation of electron-hole pairs in the sample due to the raster scanning of a focused laser beam with energy equal or greater than the band gap energy and synchronized detection of resultant current profile with respect to the beam positions. OBIC is particularly suitable to localize defect sites caused by metal-semiconductor interdiffusion or electrostatic discharge (ESD). OBIC signals, thus, are capable of revealing the parameters/factors directly related to the reliability and efficiency of the electronic device under test (DUT). In this review, the basic principles of OBIC microscopy strategies and their notable applications in semiconductor device characterization are elucidated. An overview on the developments of OBIC microscopy is also presented. Specifically, the recent progresses on the following three OBIC measurement strategies have been reviewed, which include continuous laser based single photon OBIC, pulsed laser based single photon OBIC, and multiphoton OBIC microscopy for three-dimensional mapping of photocurrent response of electronic devices at high spatiotemporal resolution. Challenges and future prospects of OBIC in characterizing complex electronic devices are also discussed. HIGHLIGHTS: Characterization of electronic device quality is of paramount importance. Optical beam induced current (OBIC) microscopy offers spatially resolved mapping of local electronic properties. This review presents the principle and notable applications of OBIC microscopy.