Low defect density amorphous hydrogenated silicon prepared by homogeneous chemical vapor deposition

Abstract

Compositional, structural and transport data are presented for amorphous hydrogenated silicon (a-Si:H) prepared by homogeneous chemical vapor deposition (HOMOCVD). We find a remarkable similarity in properties between HOMOCVD and plasma a-Si:H, including a nearly identical range (250–300 °C) for the preparation of highly photoconductive films. However, unlike plasma material, HOMOCVD a-Si:H exhibits negligible photo-induced instabilities (Staebler–Wronski effect) and low spin concentrations over a wide span of deposition conditions. These results indicate that a significant defect-creating reaction, most likely surface Si-H bond scission, is occurring in the plasma environment, but absent in HOMOCVD.

Vibrational resonance in a multistable system with position-dependent mass

“…To get a clearer picture, we present the system's potential plot from equation (13) in figures 1(a) and (b) for four different values of the mass nonlinear strength a. Figure 1(a) depicts a symmetric periodic potential with periodicity k and potential barrier V k 0 for PDM parameters (m 0 , a) = (1, 0) representative of equation (6). Clearly, the perturbed potential (13) is reduced to equation (6)at a = 0, giving rise to the symmetry in the potential structure [39,45].…”

“…This phenomenon is well-known as multistability [1]. Studies on multistable systems are interdisciplinary and have gained attention in various fields of science such as neuroscience [2], lasers and optics [3], condensed matter physics [4], chemistry [5,6], rheology [7], nuclear physics [8], ecology [9], fluid-dynamics [10,11], semiconductor physics [12] and biology [13]. Experimental and theoretical models have revealed distinct paths to multistability in various systems such as weakly dissipative systems [14], coupled systems [15], delayed feedback systems [16], parametrically excited systems [17], and stochastic systems [18].…”

Peculiarities of nanocrystalline silicon films growth on porous anodic alumina surface

“…The variety of direct CVD techniques has been used to yields materials with good optoelectronic properties [4][5][6][7][8][9]. But among them only plasma enhanced chemical vapor deposition (PE CVD) has been established for industrial applications [10].…”