| AVS 55th International Symposium & Exhibition | |
| Electronic Materials and Processing | Thursday Sessions |
| Session EM-ThP |
| Session: | Electronic Materials and Processing Poster Session |
| Presenter: | B.D. Thoms, Georgia State University |
| Authors: | R.P. Bhatta, Georgia State University A.R. Acharya, Georgia State University B.D. Thoms, Georgia State University M. Alevli, Georgia State University N. Dietz, Georgia State University |
| Correspondent: | Click to Email |
The presence of surface electron accumulation on a semiconductor has been shown to affect the properties of metallic contacts and may be important in determining other properties of devices. Adsorbates have been shown to affect the electron density on InAs surfaces, however, the effects on the surface electron concentration for InN have not been established. In this work, the effects of adsorbates on surface electron accumulation for N-polar InN have been studied by high resolution electron energy loss spectroscopy (HREELS). By varying the energy of the incident electrons the probing depth can be varied. Shifts in the energy of the conduction band plasmon indicate differences in plasma frequency and therefore differences in free carrier concentration as a function of depth from the surface. By this method it is shown that hydrogen-terminated N-polar InN exhibits surface electron accumulation. Heating InN for 15 minutes at 425°C desorbs the surface hydrogen without surface damage or film decomposition. HREELS of bare N-polar InN indicates the presence of surface electron accumulation and confirms that no surface indium is present. These results indicate that surface electron accumulation is not due to indium-indium bonding and is not affected by the presence or absence of surface hydrogen, but may instead be intrinsic to the N-polar InN surface. The effects of other adsorbates, such as oxygen, will also be discussed.