Crystallization and silicon diffusion nanoscale effects on the electrical properties of Al2O3 based devices

Conductivity and Charge Trapping After Electrical Stress in Amorphous and Polycrystalline $\hbox{Al}_{2}\hbox{O}_{3}\hbox{-Based}$ Devices Studied With AFM-Related Techniques

“…GIXRD measurements show that the Al 2 O 3 layer crystallizes at a temperature between 850 • C and 900 • C [23]. These observations are further supported by TEM images.…”

“…Moreover, except for the sample annealed at 900 • C, the electrical conductivity is lower for crystalline structures annealed at the lowest T A . Finally, it can be observed that, for both groups, crystalline and amorphous oxides, a higher T A results in a smaller mean value (larger conductivity) and a higher deviation of the onset voltage (larger inhomogeneity) [23]. The explanation for the particular electrical behavior of the sample annealed at 900 • C could be related to changes in the physical thickness of the layers of the stack during annealing.…”

“…The most remarkable result is the dependence of the percent of silicon on T A . In particular, it was observed that, the higher the T A , the higher the content of silicon diffused from the substrate into the Al 2 O 3 stack [23].…”

On the use of two dimensional hexagonal boron nitride as dielectric

“…In 2008, in the 45 nm node, the traditional SiO 2 gate insulator started to be replaced by thin films of high-k materials, such as HfO 2 or Al 2 O 3 [11][12][13]. Nevertheless, replacing SiO 2 , which only has one disadvantage (its low dielectric constant), by high-k dielectrics was a painful process as, in principle, these materials only have the advantage of reducing the leakage current.…”

Correlation between the nanoscale electrical and morphological properties of crystallized hafnium oxide-based metal oxide semiconductor structures

“…[3][4][5][6][7] Conductive atomic force microscopy ͑CAFM͒ has been widely used to evaluate the electrical conduction of polycrystalline high-k dielectrics. Whereas some studies have suggested that conduction through the polycrystalline films occurs primarily through the bulk of the grains, 8,9 others have demonstrated that the leakage current flows preferentially through the grain boundaries ͑GBs͒, 3,7,10,11 which agrees with the results of ab initio calculations. 12 Besides generally expected differences associated with the intrinsic properties of the studied materials, such a discrepancy could be caused by the limits of the CAFM lateral resolution, which are close to the characteristic GB width.…”