Grain Growth and Conductive Characteristics of Super Thin Polysilicon Films by Oxidation

Abstract

Improved characteristics of electronic conduction and grain growth effect of super thin CVD polysilicon films after thermal oxidation (less than 1000 Å thick) were investigated. After oxidation of CVD silicon, grain size grew two-dimensionally to as large as 1500 Å in diameter with a thickness of 300 Å. In contrast, temperature dependence of conductivity changed from T -(1/4) rule to T -1 rule after oxidation. The grain growth effect after oxidation to super thin films (200–300 Å thick) was found to affect the decrease in grain boundary barrier height, which resulted in the increase of carrier mobility.

Advanced Superthin Polysilicon Film Obtained by Si+ Implantation and Subsequent Annealing

“…Temperature dependences of electron mobility deduced from SFT compared to an unimplanted one (10) are shown in Fig. 8.…”

“…Silicon nitride is of particular importance as an insulation and passivation material (1). To date, studies of the LPCVD nitride process have primarily been experimental (2)(3)(4)(5)(6)(7)(8)(9)(10). These studies have characterized how reactor operating parameters affect the nitride film stoichiometry (6, 10), masking ability (5), electrical properties (7,9), and stress (8)(9)(10).…”

“…To date, studies of the LPCVD nitride process have primarily been experimental (2)(3)(4)(5)(6)(7)(8)(9)(10). These studies have characterized how reactor operating parameters affect the nitride film stoichiometry (6, 10), masking ability (5), electrical properties (7,9), and stress (8)(9)(10). Theoretical approaches to the understanding of the salient chemistry and kinetics in the nitride process have not yet been accompanied by supporting experiments (11).…”