P. Kleimann et al., STRESS-DEPENDENT HOLE EFFECTIVE MASSES AND PIEZORESISTIVE PROPERTIES OF P-TYPE MONOCRYSTALLINE AND POLYCRYSTALLINE SILICON, Physical review. B, Condensed matter, 57(15), 1998, pp. 8966-8971
Piezoresistive effects of p-type polycrystalline silicon underline tha
t longitudinal and transversal piezoresistive properties in monocrysta
lline silicon do not have the same physical origin, which is not accou
nted for in current models. This difference is highlighted by the stud
y of the mechanical stress effect on the valence band, which shows tha
t piezoresistive properties of p-type monocrystalline silicon can he e
xplained in terms of both hole transfer between heavy-and light-hole v
alence bands and stress-dependent hole effective masses. The quantific
ation of these phenomena points out that longitudinal piezoresistive p
roperties are mainly due to the hole transfer, whereas transversal one
s an mainly attributed to the effective mass change effects. This enab
les one to model p-type polycrystalline silicon piezoresistivity, in p
articular the sign change of the transversal gauge factor at high dopi
ng level. [S0163-1829(98)01615-4].