Agency for Science, Technology and Research

National University of Singapore

Other

Chew Kiat Heng

Yu Jau Chen

Tit Meng Lim

Yubo Miao

Quanbo Zou

Tie Yan

Janak Singh

Disposable units in current use for performing PCR are limited by their heat block ramping rates and by the thermal diffusion delay time through the plastic wall as well as by the sample itself. This limitation has been overcome by forming a disposable plastic chip using a simple deformation process wherein one or more plastic sheets are caused, through hydrostatic pressure, to conform to the surface of a suitable mold. After a given disposable chip has been filled with liquid samples, it is brought into close contact with an array of heating blocks that seals each sample within its own chamber, allowing each sample to then be heat treated as desired.

Shallow multi-well plastic chip for thermal multiplexing

Formation of micro-fluidic systems is normally achieved using a multi-wafer fabrication procedure. The present invention teaches how a complete micro-fluidic system can be implemented on a single chip. The invention uses only dry etch processes to form micro-chambers. In particular, it makes use of deep reactive ion etching whereby multiple trenches of differing depths may be formed simultaneously. Buried micro-chambers are formed by isotropically increasing trench widths using an etchant that does not attack the mask so the trenches grow wider beneath the surface until they merge. Deposition of a dielectric layer over the trenches allows some trenches to be sealed and some to be left open. Micro-pumps are formed by including in the micro-chamber roof a layer that is used to change chamber volume either through electrostatically induced motion or through thermal mismatch as a result of its being heated.

Process to fabricate an integrated micro-fluidic system on a single wafer

Growing community of inventors

Singapore, Singapore

Chew Kiat Heng