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URO Fall 2004

8 Sep 2004

Attached is the LabVIEW programs. Without the hardware, you cannot run the program, but you can still look at it. LabVIEW evaluation version can be run for 15 min, after that it will close automatically. Then you have to start it again.


            FYI, the Raman spectroscopy system is from this company

                   The motors are from this company  


DLL and LabView  05 Sep 2004

2004 EECS Research Summary
Contents of Chapter 4: Integrated Circuits

CMOS Multi-Mode Linear/Efficient Power Amplifier
Gang Liu
(Professors Ali Niknejad and Tsu-Jae King)
Analog Devices

The recent explosion in consumer applications for radio frequency (RF) and wireless systems has resulted in an extensive research and design effort to develop low-cost implementations of RF integrated circuits. CMOS technology has played an important role in providing higher functionality and complexity at low costs. The single-chip RF transceiver, implemented by low-cost commercial CMOS technologies, is a good solution for these devices mentioned above. RF receiver circuits, such as low noise amplifiers, mixers, and voltage-controlled oscillators have been reported in the integrated forms [1]. Recently, a fully integrated non-linear CMOS PA has been shown [2].

Modern communication systems employ spectrally efficient modulation schemes which require linear PAs. Backward compatibility with existing networks require efficient non-linear PAs. However, successful demonstration of a fully integrated linear power amplifier has been one of the major holdups preventing the implementation of a single-chip next generation wireless system.

Our research proposes to design a multimode fully integrated CMOS power amplifier capable of switching between linear class A/AB operation for next generation wireless systems and high efficiency class F operation to allow backwards compatibility of current standards.

The integration of Si active devices with advanced micromechanical (MEMS) devices on one chip is considered the next step for communication systems. This research will investigate SiGe MEMS technology to implement post CMOS processing to obtain high qualify, fully integrated passives to further improve the performance of PAs.

Luke Lee, Ph.D., UCB
Assistant Professor, Bioengineering
Associate Director, Berkeley Sensor & Actuator Center
Contact Information:
Office: 455 Evans Hall
Box/Mail Code: MC 1762
Telephone(s): (510) 642-5855
Fax: (510) 642-5835

Gang Liu

PhD student in EECS
research interests: Analog RF IC, MEMS, integrated technology
advisor: King
email: liugang@eecs
phone: 510-642-1010
country of origin: P.R. China
previous degrees: BE in Engineering

 Liu, Gang's home

Luke Lee: New DNA Detectors Bridge the (Nano)Gap

By David Pescovitz

Printer-friendly version

A bio-nano breakthrough at UC Berkeley may someday lead to devices that diagnose disease, detect evidence of bioterrorism, and aid in the discovery of new drugs. Most impressive though is that these devices, based on a DNA-sensing chip in development at Berkeley, will fit in your pocket.

Bioengineering professor Luke Lee, co-director of the Berkeley Sensor and Actuator Center, and his students recently demonstrated a tiny chip that instantly identifies DNA by its electrical properties.

Already available DNA microarrays, or "gene chips," enable the analyses of DNA samples to identify biological substances. The silicon or glass chips are embedded with tens of thousands of different fragments of DNA whose double helix structure has been separated into single strands. Each bit of reference DNA consists of a specific sequence of bases - the four letters that spell out the genetic code- that are unique to a particular disease or biomaterial the user is attempting to identify.

The sample-of-interest is also separated into single strands and then introduced onto the chip for analysis. Because certain letters in DNA always connect to specific other letters, the sample will only bind, or hybridize, with its complementary strand. By detecting which reference fragment the DNA sample binds most tightly to, the user can identify the DNA in question. The hassle though comes in trying to detect when the DNA strands bind, or hybridize.

"Most DNA detection systems are based on optical detection," Lee says. "You have to label the DNA with a fluorescent molecule, excite it with a laser, and then detect the fluorescence."

Not only is that process time-consuming, Lee explains, but the optical apparatus is bulky and expensive.

Lee's approach is to replace the optics with electronics. Using novel nanotechnology batch-fabrication techniques, Lee creates polysilicon chips riddled with nanogap junctions, chasms just 50 nanometers wide. Immobolized within each nanogap is a single strand of reference DNA. A voltage is then applied across the nanogap and a measurement is taken of the capacitance, the ability of the conductors to store charge. The capacitance is determined by the dielectric (insulating) property of the material in the nanogap, which changes as a result of hybridization.

"Then you add the sample DNA and measure the difference after hybridization," Lee says. "You look for a complementary match based on the electrical signal."

Currently, Lee and his team are working to improve the sensitivity of their device. The next step in the research, he says, is to design a nanofluidic system, essentially nanoscale plumbing, the control the flow of the DNA samples through the nanogap junction arrays.

"Our work," Lee says, "is really at the interface between solid state electronics and soft state biopolymers," molecules formed by living organisms.
04 Sep 2004

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Electrical Engineering 141 Fall 2003: Teaching Assistant Gang Liu

URO project index

Bioengineering URO Project

Professor Luke Lee
455 Evans Hall


*Biomedical Polymer Opto Electro Mechanical Systems

We are developing a novel microsystem that combines
biocompatible polymer micromachining technology,
nano- and microfluidics, optoelectronics, single photon
avalanche-diodes, and active micro-optical control
devices to realize stand-alone µ-laser induced
fluorescence (µLIF) microsystems, µ-confocal imaging
arrays (µCIA), and integrated near-field optical
microfluidic devices (INFOMD) for ultra sensitive
bioassays with single-molecule detection sensitivities.
The hybridization of biocompatible polymer
micromachining technology, microlasers, active
biomimetic microlens, waveguides, and single photon
avalanche-diodes would enable critical capabilities of
microsystems for total bioanalysis. The hybrid bioassay
microsystems could be used for analyzing biological
samples for the detection of single DNA molecules,
subcellular organelles, or neurotransmitters.

Qualifications: Dedicated spirit with basic background in chemistry and physics.