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Impacts of silicon, carbon, and oxygen interfacial impurities on the performance of high‐voltage vertical GaN‐based p–n diodes are investigated. The results indicate that moderate levels (≈5 × 1017 cm−3) of all interfacial impurities lead to reverse blocking voltages (Vb) greater than 200 V at 1 μA cm−2 and forward leakage of less than 1 nA cm−2 at 1.7 V. At higher interfacial impurity levels, the performance of the diodes becomes compromised. Herein, it is concluded that each impurity has a different effect on the device performance. For example, a high carbon spike at the junction correlates with high off‐state leakage current in forward bias (≈100× higher forward leakage current compared with a reference diode), whereas the reverse bias behavior is not severely affected (> 200 V at 1 μA cm−2). High silicon and oxygen spikes at the junction strongly affect the reverse leakage currents (≈ 1–10 V at 1 μA cm−2). Regrown diodes with impurity (silicon, oxygen, and carbon) levels below 5 × 1017 cm−3 show comparable forward and reverse results with the reference continuously grown diodes. The effect of the regrowth interface position relative to the metallurgical junction on the diode performance is also discussed. [ABSTRACT FROM AUTHOR]

Critiques recent research on the social evaluation of assertive speech. Proposes an alternative theoretical framework, based on speech act theory. Assertiveness is viewed as a style of conversation occurring in complex interpersonal contexts. (Author/BJV)

Contains a selection of works on feminist theory and method. Presents a description of types of articles contained in each of the following sections of the bibliography: (1) "Epistemology and Metatheory"; (2) "Critical Analysis and Reformulations"; (3) "Applications"; and (4) "Further Resources." A total of 232 entries is listed. (JS)

Multiple-quantum-well light-emitting diode (LED) structures of InGaN/GaN were grown by metalorganic chemical vapor deposition on Si(111) substrates via ZrB2(0001) buffer layers and a GaN template comprising composite AlxGa1-xN (where x lies in the range from 0 to 1) transition layers to minimize cracking due to thermal expansion mismatch between Si and GaN. Photoluminescence and electroluminescence results from the LED structures compared favorably with similar measurements obtained on identical LED structures grown on sapphire substrates. However, in spite of all the precautions taken, cracking was still present in the LED structures. Scanning electron microscopy and transmission electron microscopy in plan-view and cross-section geometries were conducted on the LED structures to examine the presence and the influence of various defects such as microvoids, micropipes, and threading dislocations on the mechanism of cracking. Our results suggest that the crack network propagates from microvoids on the surface of the LED structure. The formation of microvoids appears to originate from imperfections in the epitaxial ZrB2(0001) buffer layer. [ABSTRACT FROM AUTHOR]

A proposed standard definition for the use of the words sex and gender is viewed as simplistic since the problems associated with these two terms are conceptualrather than terminological. The need to address the differing epistemologies involving sex-related causality that co-exist in the field is instead emphasized. Psychologists are urged to continue to modify terminology as the requirements of scientific inquiry call for.

What factors predict self-identification as a feminist? College women (N = 233) were given measures of feminist ideology; feminist identity development; evaluation of feminists, collectivism, and individualism. Feminist identification was measured both as a dichotomous and a continuous variable. Measured dichotomously, feminist self-identification was predicted by not having conservative beliefs and having a positive general evaluation of feminists. In addition, self-identified feminists were more likely to believe in collective action; to hold liberal, radical, and womanist ideologies; and to endorse items in the Synthesis stage of identity development. They were less likely to believe a feminist is a lesbian, to endorse items in the Passive Acceptance stage, and to believe in the existence of a meritocracy. Measured continuously, degree of feminist identity was predicted by having a positive general evaluation of feminists, not having conservative beliefs, and endorsing items in the Revelation and Embeddedness/Emanation stages of identity development. The two measures of feminist identity were not entirely congruent, underlining the importance of methodological differences in measuring social identity.

When a woman says 'I am a feminist' what does she mean? What do other people think she means? We asked 71 women to complete the Feminist Perspectives Scale (Henley, Meng, O'Brien, McCarthy, & Sockloskie, 1998) from their own perspective and from the perspective of a 'typical feminist.' Women who self-identified as feminists had stronger beliefs than those who did not on all feminist perspectives except cultural feminism. Both groups believed that a typical feminist held stronger radical, socialist, and cultural feminist beliefs than they themselves did, although the discrepancies were greater for nonfeminists. Nonfeminists viewed a typical feminist as endorsing stronger cultural feminist views than did feminists. Our results indicate that feminist self-identity is related to endorsement of feminist ideologies, and that both feminists and nonfeminists think that a typical feminist is more extreme than they are. The results also suggest that cultural feminism is a contested ideology; it is not endorsed by feminists, but is ascribed to them by nonfeminists.