Evaluation of different oxidation methods for silicon for scanning capacitance microscopy
2001 (English)In: Materials Science in Semiconductor Processing, ISSN 1369-8001, Vol. 4, no 03-jan, 81-84 p.Article in journal (Refereed) Published
Different oxides, namely, native, thermal, and wet-chemical (H2SO4 + H2O2 based) oxides on Si are evaluated in the context of scanning capacitance microscopy (SCM). The samples investigated consisted of uniformly doped Si substrates and p-type epitaxial doping-staircase structures with concentrations ranging from 5 x 10(14) to 2 x 10(19) cm(-3) The bias for which the SCM signal (dC/dV) is maximised for the lowest doped region was used for comparing the different oxidation methods. It is shown that for a better evaluation of the surface oxide properties, it is essential to obtain dC/dV curves for a sufficiently large doping range. Best results in terms of low values of flat-band voltages (1 V), uniformity, and consistency across a large doping range were obtained for the wet-chemical oxide. For the native oxide case, the difference in the dC/dV peak bias Values obtained at regions doped to 5 x 10(14) to 10(17) cm(-3) was anomalously large and suggests appreciable distortion of the dC/dV curves. For the same oxidation procedure the full-width at half-maximum of the dC/dV curve obtained on the cleaved surface is typically 2 times larger than that on the planar (100) surface. It is most likely that interface states are responsible for the observed distortion.
Place, publisher, year, edition, pages
2001. Vol. 4, no 03-jan, 81-84 p.
SCM, Si, oxide, flat-band voltage
IdentifiersURN: urn:nbn:se:kth:diva-20481ISI: 000167727200019OAI: oai:DiVA.org:kth-20481DiVA: diva2:339176
QC 201005252010-08-102010-08-10Bibliographically approved