Si CHANNEL SURFACE DEPENDENCE OF ELECTRICAL CHARACTERISTICS IN ULTRA-THIN GATE OXIDE CMOS

摘要

The properties of ultra-thin gate MOSFETs on various surface oriented Si substrates were investigated. The behavior regarding low field mobility in n- and p-MOSFETs on (111) and (110) substrates was the same as in the thicker oxide case. Transconductance of p-MOSFETs on (110) substrate was 1.9 times greater than that for (100) substrates. In the case of (111) substrate, it was found that some of the properties and reliability for ultra-thin SiO_2 film and MOSFETs are very good and quite different from those in the thicker oxide case. In addition, the improvement of electrical characteristics of MOSFETs on (100) Si substrate using epitaxial Si channel technique was demonstrated. With thinning of the gate insulators, the quality control of Si/insulator interface becomes important.