In this paper we review paramagnetic point defects in amorphous silicon nitride thin films. We will discuss two intrinsic paramagnetic defects: a trivalent silicon center, named the K-center, and the recently observed nitrogen dangling-bond center. We examine the structural identification, and the electronic properties of the K-center, as well as consider why a-SiNx:H is generally a very effective charge trapping dielectric. In addition, this paper compares and contrasts special features of the structure and electronic role of the paramagnetic point defects in both silicon dioxide and silicon nitride thin films; this may provide insight for further studies on the physics and chemistry of these dangling-bond centers in both materials. © 1991, The Electrochemical Society, Inc. All rights reserved.