Secondary electron dopant contrast imaging of compound semiconductor junctions

Secondary electron imaging combined with immersion lens and through-the-lens detection has been used to analyze various semiconductor junctions. Dopant contrast imaging was applied for multi-doped 4H-SiC, growth-interrupted n+/p and n/n+ homoepitaxial interfaces, and an AlGaAs/GaAs p-n junction light-emitting diode structure. Dopant contrast was explained by the local variation in secondary electron escape energies resulting from the built-in potential difference. The effect of varying electron affinity on contrast for the heterostructures is also discussed. The contrast profile of the n-doped AlGaAs compared reasonably well to the simulated valence bandedge energy using a previously determined efficiency of dopant ionization. 2011 American Institute of Physics.

Chung, S., Wheeler, V., Myers-Ward, R., Nyakiti, L. O., Eddy, C., Gaskill, D. K., Skowronski, M., & Picard, Y. N.

Chung, Suk||Wheeler, Virginia||Myers-Ward, Rachael||Nyakiti, Luke O||Eddy, Charles R Jr||Gaskill, D Kurt||Skowronski, Marek||Picard, Yoosuf N

Secondary electron dopant contrast imaging of compound semiconductor junctions Academic Article