Potassium and ion beam induced electron accumulation in InN

Abstract

a b s t r a c t "We present angle resolved photoemission study of quantized electron accumulation subbands obtained from both clean and potassium deposited InN(0001) surfaces. Shifting of the quantized accumulation states toward higher binding energies upon low energy N 2 + ion bombardment or a small amount of potassium adsorption is explained by the modification of the In-adlayer induced surface states. N 2 + ion bombardment leads to a higher density of donor-type surface states by creating nitrogen vacancies near the surface. On the other hand, a small amount of K adsorbates initially donate their free electron to InN and result in more pronounced downward band bending. Eventually, further K adsorption leads to passivation of surface states and reduction of the surface electron accumulation. With the increase of the electron density, enhanced many-body interactions of electrons within the electron accumulation layer are observed."

Photoemission response of 2D electron states

“…Semiconductor surfaces can also bear QW-states formed from bulk CB states confined in the surface band-bending V(r). A recent example is InN where the band bending can be tuned, for example, by absorption of potassium (Colakerol et al 2015) or water (Jovic et al 2017). These QWstates demonstrate the same periodic ARPES response pattern (Jovic et al 2017).…”

Effect of a skin-deep surface zone on the formation of a two-dimensional electron gas at a semiconductor surface

“…Two-dimensional electron gases (2DEGs) occurring at surfaces of semiconductors have been studied for many years due to their rich phenomenology and extreme technological relevance [1][2][3][4][5][6][7][8][9][10][11][12][13]. The 2DEGs arise following subsurface confinement of conduction electrons caused by an electric field.…”

How Indium Nitride Senses Water

“…This is reasonable if we consider that up to four sub-bands have been experimentally shown by our group on InN films with higher charge carrier concentrations. 33 From the Fourier transform of Ψ , we further predict the k z dependence of the Fermi surface, shown in Fig. 3 (d), and compare it to the experimental ARPES result around Γ 0004 in Fig.…”