TY - CHAP
T1 - A novel polishing stop for accurate integration of potassium yttrium double tungstate on a silicon dioxide
AU - Van Emmerik, Carlijn I.
AU - Martinussen, Simen M.
AU - Mu, Jinfeng
AU - Dijkstra, Meindert
AU - Kooijman, Roy
AU - García-Blanco, Sonia M.
PY - 2018/1/1
Y1 - 2018/1/1
N2 - Rare-earth ion doped potassium yttrium double tungstate, RE:KY(WO4)2, is a promising candidate for the realization of on-chip lasers and amplifiers. Two major bottlenecks difficult the realization of compact, high-contrast devices. Firstly, the crystal can only be grown on a lattice matched substrate, leading to a low (<2×10-2) refractive index contrast between core and cladding. Secondly, the required thickness for the high-index contrast waveguides, ∼1 μm, makes a lapping and polishing approach very challenging. In this work we propose a novel polishing stop that will permit to accurately control the final thickness of the KY(WO4)2 waveguide within a few tens of nanometers. A 1 mm thick KY(WO4)2 substrate is flip-chip bonded with an adhesive layer onto a SiO2 substrate. Afterwards a low temperature pulsed laser deposited (PLD) Al2O3 layer-with the desired final thickness of the KY(WO4)2 waveguide core-is deposited on top of the assembly. The sample is then thinned using a multistep lapping and polishing procedure. Earlier work with a polishing stop made from SiO2, showed a decrease of the polishing speed with a factor 3-4, allowing the termination of the process within a tolerance of a few tens of nanometers.
AB - Rare-earth ion doped potassium yttrium double tungstate, RE:KY(WO4)2, is a promising candidate for the realization of on-chip lasers and amplifiers. Two major bottlenecks difficult the realization of compact, high-contrast devices. Firstly, the crystal can only be grown on a lattice matched substrate, leading to a low (<2×10-2) refractive index contrast between core and cladding. Secondly, the required thickness for the high-index contrast waveguides, ∼1 μm, makes a lapping and polishing approach very challenging. In this work we propose a novel polishing stop that will permit to accurately control the final thickness of the KY(WO4)2 waveguide within a few tens of nanometers. A 1 mm thick KY(WO4)2 substrate is flip-chip bonded with an adhesive layer onto a SiO2 substrate. Afterwards a low temperature pulsed laser deposited (PLD) Al2O3 layer-with the desired final thickness of the KY(WO4)2 waveguide core-is deposited on top of the assembly. The sample is then thinned using a multistep lapping and polishing procedure. Earlier work with a polishing stop made from SiO2, showed a decrease of the polishing speed with a factor 3-4, allowing the termination of the process within a tolerance of a few tens of nanometers.
KW - Bonding
KW - Heterogeneous integration
KW - Integrated optics
KW - Lapping
KW - Polishing.
KW - Potassium double tungstate
KW - heterogeneous integration
KW - lapping
KW - thinning
KW - bonding
KW - polishing
KW - high-contrast waveguide
KW - integrated optics
KW - potassium double tungstate
UR - http://www.scopus.com/inward/record.url?scp=85047721244&partnerID=8YFLogxK
UR - https://www.spiedigitallibrary.org/conference-proceedings-of-spie/10535/2289955/A-novel-polishing-stop-for-accurate-integration-of-potassium-yttrium/10.1117/12.2289955.full
UR - http://www.mendeley.com/research/novel-polishing-stop-accurate-integration-potassium-yttrium-double-tungstate-silicon-dioxide-platfor
U2 - 10.1117/12.2289955
DO - 10.1117/12.2289955
M3 - Chapter
AN - SCOPUS:85047721244
SN - 9781510615557
VL - 10535
T3 - INTEGRATED OPTICS: DEVICES, MATERIALS, AND TECHNOLOGIES XXII
SP - 27
BT - Integrated Optics: Devices, Materials, and Technologies XXII
A2 - García-Blanco, Sonia M.
A2 - Cheben, Pavel
PB - SPIE
T2 - SPIE Optoelectronics and Photonic Materials and Devices Conference, OPTO 2018
Y2 - 28 January 2018 through 2 February 2018
ER -