A-C Properties of Anodic Oxide Films on Silicon

Abstract

Low resistivity (∼0.02 ohm cm), (111)‐oriented, p‐type silicon slices were anodized in a solution of 0.04N KNO3 in ethylene glycol containing 2% water, and the dielectric behavior of the system normalSi/anodic SiO2/normalelectrolyte has been studied. It was found that the reciprocal capacitance decreased proportionally to the square root of time during which the sample was immersed in a measurement electrolyte. Denning a “diffusion constant,” 2D=false(εεo·A)2∂false(1/C)2/∂t , it was found that D was not affected by the pH of the measurement electrolyte but increased (i) with the water content of the electrolyte, (ii) with temperature, and (iii) with anodic bias. An activation energy of 0.66 ev has been determined between 0° and 75 °C. It is suggested that water, after entering the anodic oxide, dissociates into hydroxyl groups which migrate into the oxide and cause the effective dielectric thickness to decrease. Partial dehydration was possible by annealing or by evacuation. The frequency dependence of the capacitance, when measured in an electrolyte of low water content, (i) increased with film thickness for oxide layers formed at the same current density, and (ii) decreased with increasing formation current density for constant film thickness.

Hydrides and Hydroxyls in Thin Silicon Dioxide Films

“…Subsequently, several hundred papers concerned with both theoretical and experimental aspects of Lang topography have been reported. However, although there have been numerous modifications to the technique for particular applications (3)(4)(5), Lang topography in most common use today remains essentially the same as when first introduced.…”

Annealing effects on the operation stability of ballistic electron emission from electrochemically oxidized nanocrystalline silicon diodes

“…11 Incorporated hydrogen generates precursor defects that cause local dielectric breakdown in nanometer-thick SiO 2 layers. 12,13 In this model, hydrogen in a SiO 2 layer migrates and extracts another terminated hydrogen as follows: wSiHϩH 0 →wSi•ϩH 2 , where wSi• represents a Si atom backbonded to c-Si with a dangling bond that was initially passivated by hydrogen.…”

Theoretical Model of the Anodic Oxidation Growth Kinetics of Si at Constant Voltage

“…By least squares analysis, the slopes of the linear regions are Substituting the mobility from Eq. [21] into [20], we obtain slope = K~e [22] We define vi~, Xoi,, Vin, Jein, and Ei~ as initial velocity, initial oxide thickness, initial voltage, initial electronic current density, and initial electric field, at the start of the linear region of oxide growth. From Fig.…”