Structural and electrical characteristics of Ge nanoclusters embedded in Al2O3 gate dielectric

Abstract

Structural and electrical characteristics of the metal–insulator–semiconductor (MIS) structures of Al/Al2O3/Si containing Ge nanoclusters are experimentally demonstrated. Secondary ion mass spectroscopy results indicate the out-diffusion of Ge after annealing at 800 °C in N2 ambient for 30 min. An increment of leakage current is observed due to the out-diffusion of Ge. Capacitance–voltage studies indicate that annealing can effectively passivate the negatively charged trapping centers. Memory effect of the Ge nanoclusters is verified by the hysteresis in the C–V curves in the annealed sample.

Theoretical study of the insulating oxides and nitrides: SiO2, GeO2, Al2O3, Si3N4, and Ge3N4

“…These nanocrystals are embedded in an insulating matrix which is usually chosen to be silica 4,5,6,7 . However, other wide bandgap materials are also employed such as germania 8,9 , silicon nitride 10,11,12 , and alumina 13,14,15 . As a matter of fact, the effect of different host matrices is an active research topic in this field.…”

The effect of the thickness of tunneling layer on the memory properties of (Cu2O)0.5(Al2O3)0.5 high-k composite charge-trapping memory devices

“…[8][9][10][11][12][13][14][15][16][17][18][19][20] To achieve good memory characteristics, some highk oxide dielectrics have been proposed and studied as the tunneling layer, chargetrapping layer and blocking layer, respectively. For example, HfO 2 , ZrO 2 , Y 2 O 3 and La 2 O 3 have been employed to replace Si 3 N 4 in SONOS memory devices to acquire better trapping characteristics, [21][22][23] and Al 2 O 3 has been employed as the tunneling layer and the blocking layer to reduce the working voltage.…”

Self-organized Ge nanocrystals embedded in HfAlO fabricated by pulsed-laser deposition and application to floating gate memory

“…However, it is still difficult to fabricate uniform and self-organized Ge nanocrystals. Most of the methods, including the thermal annealing of Ge and dielectric mixture layer, [13][14][15] Ge ion implantation, 5 and the oxidation of SiGe, 6,7 require annealing at high temperatures. Baron et al 16 has fabricated Ge nanodots on the SiO 2 matrix by low-pressure chemical vapor deposition.…”

“…The memory effect of the Ge nanocrystals with storage charge density of up to 10 12 The nanocrystal floating gate embedded in dielectrics has attracted a great deal of attention recently because it can potentially be applied in nonvolatile, high-speed, highdensity, and low-power consuming memory. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] Compared to conventional floating gate memories such as flash, a device composed of nanocrystals isolated by dielectrics benefits from a relatively low operating voltage, high endurance, fast write-erase speeds, and better immunity to soft errors. 1 For the first nano-floating-gate memory, the materials of nanocrystals and dielectrics were Si and SiO 2 , respectively.…”

“…1 In recent years, several new memory nodes such as Ge, SiGe, Au, TiN, and Ag have been investigated, and some of them were incorporated with high-k dielectrics. [3][4][5][6][7][8][9][10][11][12][13][14] The Ge nanocrystal is considered to be an ideal memory node due to its relatively small band gap compared to Si and compatibility with current complementary metal-oxide-semiconductor (CMOS) technology. However, it is still difficult to fabricate uniform and self-organized Ge nanocrystals.…”