Transfer of micro and nano-photonic silicon nanomembrane waveguide devices on flexible substrates

Abstract

This paper demonstrates transfer of optical devices without extra un-patterned silicon onto low-cost, flexible plastic substrates using single-crystal silicon nanomembranes. Employing this transfer technique, stacking two layers of silicon nanomembranes with photonic crystal waveguide in the first layer and multi mode interference couplers in the second layer is shown, respectively. This technique is promising to realize high density integration of multilayer hybrid structures on flexible substrates.

Silicon nanomembranes for high-performance flexible photonic interconnects and devices

“…In our previous work, we demonstrated the possibility of transferring photonic crystal waveguides (PCW) and multimode interference (MMI) couplers onto flexible polyimide substrate through the conventional direct peeling up approach [17]. Without elastomeric stamp, the adhesion between surfaces is difficult to control, resulting in a low transfer yield.…”

A new twist on glass: A brittle material enabling flexible integrated photonics

“…Crystalline semiconductors such as Si overcome these disadvantages of polymers. By thinning semiconductor wafers to sub‐micron thickness and transferring the resulting semiconductor nanomembranes (NMs) onto supporting polymer substrates, the NM structures can be made flexible . The hybrid NM transfer process, however, limits the yield and throughput of the approach.…”

“…By thinning semiconductor wafers to sub-micron thickness and transferring the resulting semiconductor nanomembranes (NMs) onto supporting polymer substrates, the NM structures can be made flexible. [24][25][26][27][28] The hybrid NM transfer process, however, limits the yield and throughput of the approach. In addition, NM photonic devices exhibit only moderate flexibility with a bending radius typically no less than 5 mm and cannot handle stretching deformation.…”

Stamp printing of silicon-nanomembrane-based photonic devices onto flexible substrates with a suspended configuration

“…Among all transferable single-crystal semiconductors, the silicon nanomembrane (SiNM) is one of the most promising materials because it possesses not only high carrier mobility and mechanical durability, but also optical transparency in the near-IR region, thus making it suitable for high-performance flexible optoelectronic devices. In the conventional SiNM transfer method, the patterned silicon-on-insulator (SOI) chip is put into hydrofluoric (HF) solution to selectively remove the buried oxide (BOX) layer [1][2][3][4][5][6][7][8][9][10][11]. The released SiNM settles down and is weakly bonded to the "handle" silicon wafer via van der Waals forces.…”

“…In our previous work, we demonstrated the possibility of transferring photonic crystal waveguides (PCWs) and multimode interference (MMI) couplers onto flexible polyimide substrate through the conventional directpeeling-up approach [10]. Without an elastomeric stamp, adhesion between the surfaces is difficult to control, resulting in a low transfer yield.…”