David A. Hazlebeck

Modeling of the Electroplating of a Through‐Hole Considering Additive Effects and Convection

In this paper a general mathematical model of electroplating of high aspect ratio through-holes of multilayer printed circuit boards is developed. This two-dimensional model includes transport by electrical migration, diffusion, and convection in the through-hole. The solution of the model is used to examine the effects of plating variables on uniformity in an acid copper plating bath with and without additives in the bath. Different regimes of plating conditions are examined with particular emphasis on ohmic control. The general model is used to determine the necessary conditions to achieve ohmic-limited plating. These criteria and the solution of the ohmic-limited model used determine the type of flow enhancement required to achieve ohmic-limited plating. General guidance for selection of a model for through-hole plating is developed.

Modeling of the Electroplating of a Through‐Hole with Flow Reversal and Downstream Counterelectrode Configurations

This paper reports on two process configurations of periodic flow reversal with two equistant counterelectrodes and of unidirectional flow using only a downstream counterelectrode that are analyzed using a general model of through-hole electroplating. Although plating rates greater than attained with an ohmic-limited process cannot be achieved with a flow reversal process, the flow required in the through-holes can be significantly reduced. The use of only a downstream counterelectrode can improve the uniformity of deposition and increase the plating rate over ohmic-limited plating under certain conditions.

Supercritical water oxidation of chemical agents, and solid propellants

Abstract Supercritical water oxidation (SCWO), also referred to as hydrothermal oxidation (HTO), is a developing technology for the destruction of hazardous and nonhazardous wastes. SCWO destroys combustible materials using an oxidant in water at temperatures in the range of 350°C (662°F) to 600°C (1112°F) and pressures of 17 MPa (2500 psi) or greater. General Atomics and its subcontractors are currently conducting two comprehensive research and demonstration programs geared toward the destruction of Department of Defense (DoD) wastes utilizing SCWO technology. Wastes of primary interest include chemical agents and solid propellants. Technical challenges, particularly corrosion and solids handling, were overcome, and the destruction of chemical agents and solid propellants was demonstrated on a bench scale. SCWO results for chemical agents show destruction and removal efficiencies for GB, VX, and mustard agents to be in excess of 99.9999%, limited only by detection capability. SCWO results for hydrolyzed ...