Applications of Electrochemistry to Fabrication of Semiconductor Devices

Abstract

This paper reviews some of the principal applications of electrochemistry to fabrication of semiconductor devices. Some of the electrochemical techniques used in fabrication of early semiconductor devices, such as chemical polishing, plating of contacts, dislocation etches, and junction delineation techniques continue to be used in manufacturing of present‐day devices. Principal newer uses of electrochemistry are in anisotropic etching of patterns in single crystal Si, in preferential etching of layers of a certain conductivity type or doping level without dissolution of an underlying (or adjacent) layer of Si of different type or doping level, in anodization of aluminum metallization on Si devices, and in Au plating for conductive layers in several types of silicon devices. A wide variety of other electrochemical techniques are being used in material and device characterization, and in fabrication of developmental‐type devices.

An Examination of the Chemical Staining of Silicon

“…The staining of silicon is not a new phenomenon. Over the years it has been observed to occur under a variety of silicon etching conditions, including anodic dissolution (2,3), as well as with a variety of etching solutions (4)(5)(6)(7)(8)(9)(10). Amorphous silicon (11,12), silicon hydride (13), mixtures of silicon oxides (14), and silicon monoxide or suboxide (15,16) have been proposed as compositions to account for the discolorations.…”

Surface scientific aspects in semiconductor electrochemistry

“…3), the surface of Si( 1 1 1) has been analysed by high resolution energy loss spectroscopy (HREELS). 15 This technique allows the detection of vibrational losses of primary low energy electrons impinging on the surface, measured in specula reflection geometry. The result of such an experiment in which the surface has been prepared by the aforementioned two-step electrochemical procedure is given in Fig.…”

Application of Chemical and Electrochemical Micromachining in the Electronics Industry

“…EMM through photoresist mask.--Semiconductor devices.--The use of EMM in the processing of semiconducting materials and thin metallic films has been described in several publications (70)(71)(72)(73)(74)(75)(76)(77). In these applications, due to the nature of the materials being The values within ( ) are for semiconductor materials etched, it is necessary to employ acidic or alkaline electrolytes.…”

“…During EMM, the etching stops once the junction epilayer/substrate is reached but continues in those regions that are electrically isolated from the passivated epilayer by the DP channels. Several other applications of EMM in the fabrication of semiconductor devices have been reviewed by Schnable and Schmidt (75). Booker and Stickler (76) described an electrolytic jet method of microfinishing Ge and Si to obtain flat, strain-fr~e surfaces for device fabrication.…”