• 专利标题:   Method for manufacturing large area graphene for graphene-based photonics device e.g. saturable absorber, involves several resist layers from main graphene layer to reveal final graphene layer.
  • 专利号:   US2017088944-A1
  • 发明人:   SULTANA M, LI M J, YU A W
  • 专利权人:   NASA US NAT AERO SPACE ADMIN
  • 国际专利分类:   C01B031/04, C23C016/26, C23F001/00
  • 专利详细信息:   US2017088944-A1 30 Mar 2017 C23C-016/26 201726 Pages: 16 English
  • 申请详细信息:   US2017088944-A1 US864442 24 Sep 2015
  • 优先权号:   US864442

▎ 摘  要

NOVELTY - The method involves growing a first graphene layer (201A) on one side of a metal substrate, and a second graphene layer (201B) on another side of metal substrate. The first graphene layer is coated with several resist layers. The second graphene layer and the metal substrate are removed to reveal the first graphene layer. The first graphene layer is arranged on an optical substrate. Several resist layers are removed from the first graphene layer to reveal a final graphene layer. USE - Method for manufacturing large area graphene for graphene-based photonics device such as saturable absorber (claimed) and bolometric graphene detector. ADVANTAGE - The large area monolayer and multi-layer graphene samples of optical quality for a mode locking process are fabricated effectively and reliably. The light absorption of graphene at plasmonic frequencies is enhanced. The optical absorption band of the final graphene layer is tuned to create the passband filter by controlling the size of the graphene device or by controlling the chemical potential of the graphene device. DETAILED DESCRIPTION - The first graphene layer and second graphene layer are manufactured using a low pressure chemical vapor deposition (LPCVD) technique. Several resist layers are comprised with a relatively low molecular weight polymethylmethacrylate, and a relatively high molecular weight polymethylmethacrylate. The second graphene layer and metal substrate are removed by etching. The ionic contaminants are removed after metal substrate is etched. The metal substrate is comprised of a copper. An optical substrate is comprised as a lead free optical glass with a linear optical transmission in a visible range down to 350 nm. The degasing process is performed to remove water molecules from between first graphene layer and optical substrate. Several resist layers and contaminants are removed by thermal or chemical processing. A third graphene layer is provided with several resist layers. The third graphene layer is arranged on final graphene layer which is arranged on optical substrate. A tunable plasmonic structure is formed by arranging metal layer on microscale graphene ribbons or strips to form grating coupler. An external bias voltage is applied between grating coupler and microscale graphene ribbons or strips, to electrostatically gate graphene device. The bandgaps of bilayer graphene are comprised to yield a continuously tunable photodetection bandwidth from mid-infrared (MIR) to long wave infrared (LWIR), and the programmable band gaps of graphene microscale ribbons or strips are comprised to fabricate detectors for wavelengths above 6 mu m. An INDEPENDENT CLAIM is included for a saturable absorber has a large area graphene layer is achieved by repeatedly adding additional graphene layers on third graphene layer to form multiple graphene layer structure. The final graphene layer is comprised in a laser or mode locking application, or arranged on a tip of an optical fiber. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the transfer process for large area graphene. First graphene layer (201A) Second graphene layer (201B) Copper substrate (202)