Trapping and diffusion kinetic of hydrogen in carbon-cluster ion-implantation projected range in Czochralski silicon wafers

Abstract

We investigated the diffusion behavior of hydrogen in a silicon wafer made by a carbon-cluster ion-implantation technique after heat treatment and silicon epitaxial growth. A hydrogen peak was observed after high-temperature heat treatment (>1000 °C) and silicon epitaxial growth by secondary ion mass spectrometry analysis. We also confirmed that the hydrogen peak concentration decreased after epitaxial growth upon additional heat treatment. Such a hydrogen diffusion behavior has not been reported. Thus, we derived the activation energy from the projected range of a carbon cluster, assuming only a dissociation reaction, and obtained an activation energy of 0.76 ± 0.04 eV. This value is extremely close to that for the diffusion of hydrogen molecules located at the tetrahedral interstitial site and hydrogen molecules dissociated from multivacancies. Therefore, we assume that the hydrogen in the carbon-cluster projected range diffuses in the molecular state, and hydrogen remaining in the projected range forms complexes of carbon, oxygen, and vacancies.

Trapping and diffusion behaviour of hydrogen simulated with TCAD in projection range of carbon‐cluster implanted silicon epitaxial wafers for CMOS image sensors

“…In addition, our previous study demonstrated that the dissociation activation energy of H to dissociate from the projection range of a C-cluster is 0.76 AE 0.04 eV [4]. This activation energy is extremely close to the binding energy of the C-H 2 defect and the activation energy for the diffusion of H molecules from tetrahedral interstitial sites and multivacancy [10][11][12][13][14].…”

“…We have developed proximity gettering technology with carbon (C)-cluster ion-implanted silicon (Si) epitaxial wafers for advanced complementary metaloxide-semiconductor (CMOS) image sensors [1][2][3][4]. Previous studies demonstrated that carbon-cluster ion implanted silicon epitaxial wafers have three characteristics suitable for high-performance CMOS image sensors [1][2][3][4]: a high gettering capability, an oxygen diffusion barrier effect and a hydrogen (H) passivation effect. In particular, we have reported the diffusion behaviour of H in the projection range of C-cluster implantation [4].…”

“…Previous studies demonstrated that carbon-cluster ion implanted silicon epitaxial wafers have three characteristics suitable for high-performance CMOS image sensors [1][2][3][4]: a high gettering capability, an oxygen diffusion barrier effect and a hydrogen (H) passivation effect. In particular, we have reported the diffusion behaviour of H in the projection range of C-cluster implantation [4]. H in the projection range of a C-cluster is trapped after epitaxial growth and diffused in accordance with the subsequent heat-treatment temperature.…”

“…Conventionally, H diffusion velocity is extremely high in bulk Si at high temperature [7][8][9]. Thus, only monomer-implanted H diffused to below the detection limit of secondary ion mass spectrometry (SIMS) analysis after low-temperature heattreatment at 600 8C [4]. However, C-cluster-implanted H remains in the projection range after high-temperature heattreatment at 1100 8C.…”

Effect of dose and size on defect engineering in carbon cluster implanted silicon wafers

“…14,15) Third, a passivation effect on process-induced defects is expected owing to the hydrogen in the carboncluster ions trapped in the implanted region during the device fabrication process. 16,18) However, the formation behavior of the implantation defects considered to be the gettering sinks in the implanted region around the projection range of the carbon clusters is unclear.…”