Atomic layer deposition of B2O3/SiO2 thin films and their application in an efficient diffusion doping process

Abstract

We investigated atomic layer deposition (ALD) of B 2 O 3 and SiO 2 thin films using trimethylborate (TMB) and bis-(diethylamino)silane (SAM-24) precursors, focusing on growth characteristics and film properties. For both cases, ALD processes using O 3 and O 2 plasma as reactants exhibited well-defined growth saturation and linear growth behavior without any incubation cycles, and produced highly pure, stoichiometric films. In the case of B 2 O 3 films, however, SiO 2 layer passivation is required onto the B 2 O 3 due to a spontaneous decomposition caused by moisture in air. On the basis of electrical characterization, the detailed dielectric properties of SiO 2 and B 2 O 3 /passivation SiO 2 films were extensively discussed including the k-value, flat band voltage, and leakage currents. Then, boron-doped SiO 2 films with different B/(B + Si) compositions were prepared by controlling B 2 O 3 and SiO 2 growth cycles, followed by drive-in annealing and a subsequent wet removal process. Based on both theoretical estimation and SIMS depth profile results, we demonstrated that the surface doping concentration is effectively modulated with controllable B doping contents in the B-doped SiO 2 films.

Use of B2O3 films grown by plasma-assisted atomic layer deposition for shallow boron doping in silicon

“…The reason for this type of almost complete volatilization, which was also observed by Kim et al, 10 is not quite clear. Sokolov 15 reported substantial relaxation of CVD-produced borophosphosilica glass films (BPSG) during their storage in air.…”

“…The well-established ion-implantation faces here severe limitations due to its radiative nature, which leads to structural damage, channeling in crystalline materials and shadowing effects at 3D surface features. 10 There, trimethylborate was used as boron precursor and H 2 O, O 3 , and O 2 plasma were investigated as oxidants at a deposition temperature of 150 C. The ALD of SiO 2 was applied for stabilization of the volatile B 2 O 3 films and it could be proved by XPS measurements that the boron oxide films showed B 2 O 3 type stoichiometry. The more historical technique of solid-phase diffusion from pre-deposited glass layers or high-temperature gas-phase depositions lacks in most cases the needed uniformity and dose control.…”

Boron doping-induced interconnected assembly approach for mesoporous silicon oxycarbide architecture

“…4 b) [ 36 ]. On the principle of binary phase diagram of B 2 O 3 and SiO 2 , it was reasonable to speculate that a part of B 2 O 3 can penetrate into SiO x species at the interphase [ 37 , 38 ], leading to a melt phase composed of C, SiO x and B 2 O 3 . This flowing interface layer acts like a solution, which can induce dense packing of the nanoparticles (Fig.…”

Atomic Layer Deposition of Localized Boron- and Hydrogen-Doped Aluminum Oxide Using Trimethyl Borate as a Dopant Precursor

“…48 Clusters were computed at the DFT level using the Jaguar code. 51 Electronic structure was computed using the hybrid B3LYP functional 52,53 with D3 dispersion corrections54,55 and LAV3P** basis set with an effective core potential on Al,56,57 converged in each step to energy differences < 5×10 −5 E H and RMS density matrix differences < 5×10 −6 .Growth inhibition of the TMB -O 2 plasma processFor the TMB-O 2 plasma process, a decreasing growth rate was observed during the ALD experiment in contrast with linear growth obtained in earlier work on TMB by Kim et al35 On the other hand, similar decay of growth was reported by Mane et al41 with B 2 F 4 as the…”