Dr. Jay Mathews Profile

Dr. Jay Mathews

Associate Professor

SPIE Involvement:

Author

Publications (2)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 17 February 2010 Paper

Germanium p-i-n photodiode on silicon for integrated photonic applications

Jay Mathews, Radek Roucka, Change Weng, John Tolle, José Menéndez, John Kouvetakis

Proc. SPIE. 7606, Silicon Photonics V

KEYWORDS: Sensors, Annealing, Germanium, Silicon, Chemical vapor deposition, Photoresist materials, Diodes, Silicon photonics, Semiconducting wafers, Heterojunctions

Read Abstract +

The application of silicon photonic technologies to optical telecommunications requires the development of near-infrared detectors monolithically integrated to the Si platform. Recently, efforts in this area have focused on developing detectors from pure-Ge grown epitaxially on Si substrates. Much effort has been spent on achieving growth of high quality, relaxed Ge films for device structures, but low temperature growth and processing compatible with complementary-metal-oxide-semiconductor (CMOS) technology has yet to be achieved. In this paper, we report on p-i-n heterostructure photodiodes fabricated from Ge films grown directly on Si substrates using a low temperature chemical vapor deposition (CVD) process. The heterostructures were grown on arsenic-doped (n-type) Si(100) with resistivity 0.003 Ω-cm. A 350nm thick layer of intrinsic Ge was deposited first as the active region, followed by 100nm of boron-doped (p-type) Ge. Ohmic contacts were formed by evaporation of Cr and Au. The diodes were characterized with respect to their dark currents and responsivities in the near-IR. For a 60-μm-diameter device at room temperature, the dark current densities were on the order of 10^-2 A/cm² and 10³ A/cm² at -1V and 1V, respectively, the "turn-on" voltage was found to be 0.26 V, and the ideality factor n was found to be 1.2. The external quantum efficiency of the devices was measured at room temperature over the range 1-1.8 μm. The responsivities at 1.3 and 1.55 μm were found to be 0.26 and 0.11, respectively.

Proceedings Article | 12 February 2007 Paper

Self assembled monolayer and protein adsorption studies on micromachined quartz crystal balances

Ping Kao, Abhijat Goyal, Jay Mathews, David Allara, Srinivas Tadigadapa

Proc. SPIE. 6464, MEMS/MOEMS Components and Their Applications IV

KEYWORDS: Proteins, Resonators, Quartz, Electrodes, Molecules, Crystals, Bioalcohols, Adsorption, Self-assembled monolayers, Molecular self-assembly

Read Abstract +

We report the design and fabrication of a micromachined quartz crystal balance (QCM) array for self assembled monolayers (SAMs) and protein adsorption studies. The microQCM was fabricated using recently developed inductively coupled plasma etching process for quartz to realize resonators with 60 &mgr;m thickness and electrode diameters of 0.5 mm. The reduction in the thickness and lateral pixel size has resulted in a sensitivity improvement by factor of 1700 over a commercially available macro-sized QCM. Adsorption of hexadecanethiol on the gold electrode of the QCM in ethanol at a concentration of 1 mM was recorded in real time and a frequency shift of 3650 Hz was obtained. Modeling the SAMs layer as an ideal, rigid mass layer the expected frequency shift was calculated to be 1031 Hz. This was followed by a study of the adsorption of human serum albumin (HSA) protein on the SAMs layer. For 1.5×10^-10 moles/ml concentration of protein solution in phosphate buffer solution (PBS) we obtained a frequency change of 13.28 kHz. Modeling the protein layer as a viscoelastic layer in a viscous Newtonian fluid, for saturation protein surface coverage, the frequency change was calculated to be 17.27 kHz whereas the experimentally obtained frequency change was 51.82 kHz. In both rigid and viscoelastic film adsorption experiments, we find the microQCM to exhibit three times greater sensitivity than the predicted value when operated at the third overtone. These results show that the micromachined QCM in array format is a very sensitive gravimetric sensor capable of mass resolutions into the femtograms range.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print format on SPIE.org.

PERSONAL SIGN IN
Full access may be available with your subscription

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Institutional Access:

PURCHASE THIS CONTENT

INTERESTED IN A FREE CORPORATE TRIAL?

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years