J. B. Lasky

Bio: J. B. Lasky is an academic researcher. The author has contributed to research in topics: Etching (microfabrication) & Wafer. The author has an hindex of 1, co-authored 1 publications receiving 603 citations.

Wafer bonding for silicon‐on‐insulator technologies

Abstract: A silicon wafer bonding process is described in which only thermally grown oxide is present between wafer pairs. Bonding occurs after insertion into an oxidizing ambient. It is proposed the wafers are drawn into intimate contact as a result of the gaseous oxygen between them being consumed by oxidation, thus producing a partial vacuum. The proposed bonding mechanism is polymerization of silanol bonds between wafer pairs. Silicon on insulator (SOI) is produced by etching away all but a few microns of one of the bonded pair. Capacitor measurements show a 27 μs minority‐carrier lifetime and no degradation of the SOI‐insulator interface. In addition, there is negligible charge at the bonding interface making the technique attractive for three‐dimensional as well as planar SOI applications.

Bonding of silicon wafers for silicon‐on‐insulator

Abstract: Several aspects of a new silicon‐on‐insulator technique utilizing bonding of oxidized silicon wafers were investigated. The bonding was achieved by heating in an inert atmosphere a pair of wafers with hydrophilic surfaces contacted face‐to‐face. A quantitative method for the evaluation of the surface energy of the bond based on crack propagation theory was developed. The bond strength was found to increase with the bonding temperature from about 60–85 erg/cm2 at room temperature to ≂2200 erg/cm2 at 1400 °C. The strength was essentially independent of the bond time. Bonds created during 10‐s annealing at 800 °C were mechanically strong enough to withstand the mechanical and/or chemical thinning of the top wafer to the desired thickness and subsequent device processing. A model was proposed to explain three distinct phases of bonding in the temperature domain. Electrical properties of the bond were tested using metal‐oxide‐semiconductor (MOS) capacitors. The results were consistent with a negative charge de...

Review: Semiconductor Piezoresistance for Microsystems

Abstract: Piezoresistive sensors are among the earliest micromachined silicon devices. The need for smaller, less expensive, higher performance sensors helped drive early micromachining technology, a precursor to microsystems or microelectromechanical systems (MEMS). The effect of stress on doped silicon and germanium has been known since the work of Smith at Bell Laboratories in 1954. Since then, researchers have extensively reported on microscale, piezoresistive strain gauges, pressure sensors, accelerometers, and cantilever force/displacement sensors, including many commercially successful devices. In this paper, we review the history of piezoresistance, its physics and related fabrication techniques. We also discuss electrical noise in piezoresistors, device examples and design considerations, and alternative materials. This paper provides a comprehensive overview of integrated piezoresistor technology with an introduction to the physics of piezoresistivity, process and material selection and design guidance useful to researchers and device engineers.

Frontiers of silicon-on-insulator

Abstract: Silicon-on-insulator (SOI) wafers are precisely engineered multilayer semiconductor/dielectric structures that provide new functionality for advanced Si devices. After more than three decades of materials research and device studies, SOI wafers have entered into the mainstream of semiconductor electronics. SOI technology offers significant advantages in design, fabrication, and performance of many semiconductor circuits. It also improves prospects for extending Si devices into the nanometer region (<10 nm channel length). In this article, we discuss methods of forming SOI wafers, their physical properties, and the latest improvements in controlling the structure parameters. We also describe devices that take advantage of SOI, and consider their electrical characteristics.