First Solar, Inc.

Semiconductor Diagnostics, Inc.

Semilab Semiconductor Physics Laboratory Co., Ltd.

Dmitriy Marinskiy

Jacek J Lagowski

Benyamin Buller

Marshall D Wilson

Alexandre Savtchouk

Piotr Edelman

Carlos Almeida

Bret Schrayer

Sung-Li Wang

Sheng-Shin Lin

Lin-Jung Wu

Brady A Johnson

Shyh-Shin Ferng

Joseph Nicholas Kochey

Thye Chong Loy

Yi-Hung Lin

Methods of characterizing electrical properties of a semiconductor layer structure on a wafer with topside semiconductor layers on an insulating or semi-insulating substrate, the semiconductor layer structure including a high electron mobility transistor (HEMT) heterostructure with a two-dimensional electron gas (2DEG) at a heterointerface between the semiconductor layers of the heterostructure. The methods include: (a) physically contacting the topside of the wafer within a narrow border zone at an edge of the wafer with a flexible metal cantilever electrode of a contacting device, wherein the flexible metal cantilever electrode contacts one or more of the semiconductor layers exposed at the narrow border zone so that the flexible metal cantilever electrode is in electrical contact with the 2DEG; and (b) applying corona charge bias and measuring a surface voltage of the semiconductor layers using a non-contact probe while maintaining the electrical contact with the 2DEG. The physical contacting to the topside of the wafer is noncontaminating and noninvasive to the semiconductor layers.

Topside contact device and method for characterization of high electron mobility transistor (HEMT) heterostructure on insulating and semi-insulating substrates

An example semiconductor wafer includes a semiconductor layer, a dielectric layer disposed on the semiconductor layer, and a layer of the metal disposed on the dielectric layer. An example method of determining an effective work function of a metal on the semiconductor wafer includes determining a surface barrier voltage of the semiconductor wafer, and determining a metal effective work function of the semiconductor wafer based, at least in part, on the surface barrier voltage.

Non-contact method to monitor and quantify effective work function of metals

A method and system for operating a photovoltaic module includes providing a reversed electrical bias to the photovoltaic module.

Photovoltaic device

A system for measuring quantum efficiency in a sample photovoltaic cell may include a Fourier transform infrared spectrometer. One or more light source for illuminating the photovoltaic cell in a wavelength range of interest are provided.

High speed spectrometer

The surface photovoltage dopant concentration measurement of a semiconductor wafer is calibrated by biasing the semiconductor wafer into an avalanche breakdown condition in a surface depletion region; determining a contact potential difference value corresponding to an avalanche breakdown; determining small signal ac-surface photovoltage value corresponding to an avalanche breakdown; and using the values of the contact potential and the surface photovoltage to calculate a calibration constant that relates depletion layer capacitance and an inverse of the surface photovoltage.

Self-calibration in non-contact surface photovoltage measurement of depletion capacitance and dopant concentration

A non-contact method is described for acquiring the accurate charge-voltage data on miniature test sites of semiconductor wafer wherein the test sites are smaller than 100 &#x3bc;m times 100 &#x3bc;m. The method includes recognizing the designated test site, properly aligning it, depositing a prescribed dose of ionic charge on the surface of the test site, and precise measuring of the resulting voltage change on the surface of the test site. The method further compromises measuring of the said voltage change in the dark and/or under strong illumination without interference from the laser beam employed in the Kelvin Force probe measurement of the voltage. The method enables acquiring of charge-voltage data without contacting the measured surface of the wafer and without contaminating the wafer. Thus, the measured wafer can be returned to IC fabrication line for further processing.

Non-contact method for acquiring charge-voltage data on miniature test areas of semiconductor product wafers

Growing community of inventors

Tampa, FL, United States of America

Dmitriy Marinskiy