Research Area

Fabrication and characterization and characterization of micro devices & systems

Capabilities, such as deep reactive ion etching, fusion and anodic bonding and electroplating, which are more specific to MEMS realization, will be added to enhance the existing strength of the Microelectronic Fabrication Facility. These would remove the constraint of working with limited film thickness (a few micrometers) using conventional surface micro-machining techniques, thus allowing also the readlization of "high-profile" devices. Others, such as advanced double-sides bond aligner, would allow the fabrication of complicated 3-dimensional structure. Focus will also be placed on identifying and characterizing new materials, which might enhance MEMS performance or ease device integration by improving process compatibility.

Biochips

The research activities in the area are mainly focused on the development of the genechip and lab-on-a-chip technology as well as niche applications. The program aims to develop in-house fabrication capabilities for high density genechip arrays, PCR (polymerase chain reastion) chips, and microcapillary electrophoresis systems. Niche applications will initially target TCM, including diagnostics (identification of toxic TCMs or adulterated TCMs) , genomics, and drug discovery. These areas have been selected on the basis of their immediate benefits to Hong Kong and their ptential for providing a strong foundation by which to support and encourage local investment and entrepreneurial initiatives. It is our vision that these resarch activities will significantly contribute to and support: (i) the establishment of a local genechip industry, and (ii) the local development of biotechnology and biotechnology-oriented electronics, computer hardware, and software industries.

Integrated transducers

Transducer receives signal and retransmits it in a different form. Transducers are a key components in any nano- and microsystems. Transducers find applications in a wide range of areas. In biological system, as the result of some biochemical reaction a signal was detected which can be used to trigger other biochemical reactions. This type of transducer is critically important in Smart Laboratory-on-a-chip. In environmental applications, transducers can detect air, water and food pollution. In personalized telecommunication, transducers can sense the location which a user is located so that appropriate wireless communication profile can be enabled for the user as they move from one location to another. Possible areas of research are biological / biochemical transducers, environmental transducers, transducers for telecommunications. In each of the proposed area we should be able to find application in Hong Kong as well as advance the state-of-the-art in nano- and microsystems in the world

In addition, the combination of micro-optics and integrated optics with microelectronics and micromechanics creates a broad class of micro-opto-electro-mechanical systems (MOEMS). Many devices for potential applications such as laser diode correctors / collimators, adaptive fiber couplers, hybrid refractive-diffractive color separators, fiber optic multiplexing, micro vision and illumination, optical micro sensors, optical modulation and laser communication will be developed. The ultimate goal is to construct low cost, portable, compact, robust micro optical devices to replace current bulky, touchy, expensive optical systems.

Micro &nano fluidic systems

Micro & nano thermal systems

The MEMS community is introducing a wealth of microfabricated sensors, actuators, pumps, and microfluidic devices whose functionality relies on heat transfer. Attempts to optimize these devices demand a comprehensive understanding of the fundamental thermal transport phenomena occurring at short length and time scales. The research activities in this area will focus on the systematic investigations in two-phase flow characteristics and phase-change heat transfer mechanisms in microchannels and porous structures having nano-scale pores. Specific topics include: 1) Bubble dynamics in microstructures; 2) Boiling and condensation heat transfer in microchannels; 3) Micromachined silicon inverted-meniscus evaporators; 4) Phase-change-actuated micro pumps; 5) Microscale refrigeration systems; and 6) Two-phase flow and heat transfer in micro fuel cells.

Micro & nano chemical systems

Microreactors and membrane microseparators are parts of a new paradigm in chemical engineering process that gave birth to microchemical system technology. Through miniaturization, new opportunities in chemical production, material manufacture and power generation can be exploited to satisfy the needs of a increasingly mobile society. It has been envisioned that a complete microchemical device such as microfuel cells, will consist of several major components responsible for fluid delivery, reaction and separation. A smart unit may be included to monitor, control and coordinate the performance of each of these components. A microfuel cell with power rating less than 100 W will have an enormous market demand as power unit for most portable devices including cellular phones and computers. Central to the realization of a microfuel cell device is the development of new electrode, catalyst and membrane materials that will provide more effective energy generation.

Micro-mechanics and micro-dynamics

Some fundamental scientific issues in solid mechanics and dynamics at the micrometer scale are under study. Three key issues will be addressed: 1) assessment of the testing methods for measuring the mechanical properties of MEMS materials, so as to propose standardized testing procedures; 2) analyses of the major failure mechanisms of micro structural components (e.g. micro-beams, micro-frames, micro-springs and membranes) by taking into account of size effect and surface effect which significantly influence the failure modes and criteria; and 3) examination of dynamic factors (e.g. stress waves, inertia and strain-rate sensitivity of materials) which influence the deformation and failure of micro components under shock or impact loads.

Novel materials for micro & nano systems

The research activities in this area are primarily focused on the charaterization of some smart materials such as piezoelectric materials, shape memory alloys (SMAs) and shape memory polymers (SMPs), as well as their utilization in micro systems. For instance, prototypes of SMA thin film micro-sensors and micro-actuators are under development. Applications of SMAs in medical macro- and micro-surgery will also be investigated. The application of ER fluids in transmitting forces and nano-channel ion selective membranes for chemical sensors and medical analysis will also be studied.