摘要:

The internal surface of voids present in aluminum–1% silicon metallization used in integrated circuits has been examined using Auger electron spectroscopy (AES). This surface was coated with a thin (<20 Å) layer of Al2O3in addition to nitrogen, which is believed to represent the grain boundary structure prior to void formation. Both the metal fracture surface adjacent to the void and the void surface itself showed nonequilibrium silicon concentrations of 4–6 at. % and oxygen concentrations of 9–17 at. %. The oxygen on the metal fracture surface was not associated with Al2O3or SiO2; rather, from residual gas analysis (RGA) of the sputtering environment, it is believed to be incorporated as the OH radical or water. High Si and O concentrations indicated the fracture site to be a grain boundary. Thus H, Si, O (or H2O), and N appear to be the contaminants associated with void formation and/or embrittlement in thin aluminum films.

ISSN:0734-211X    

DOI:10.1116/1.583561

出版商:American Vacuum Society    

年代:1986

数据来源: AIP

摘要:

Alloyed Au–Ge thin films onn‐GaAs are widely used for fabricating Ohmic contacts ton‐type GaAs. This paper presents a systematic study of the effects of Ge concentration on the compound formation and morphology in the metallization. The lowest annealing temperature at which the compound formation at 10−6Torr was observed for Au–Ge contacts with Ge concentrations of 0, ∼0.6, 3, and 12 wt. % Ge was 500, 500, 450, and 350 °C, respectively. Hence, Ge was found to decrease the compound formation temperature. Au7Ga2was observed in contacts with low Ge concentrations (0 and ∼0.6 wt. % Ge), whereas α’‐AuGa (or Au7Ga), a tentatively identified Au3Ga phase, and a AuGeAs ternary phase were observed in contacts with a Ge concentration of 12 wt. %. At an intermediate Ge concentration (3 wt. % Ge), both Au7Ga2and α’‐AuGa were observed. The morphology after compound formation was sensitive to the Ge concentration. In Au–Ge contacts, a change in the Ge concentration from 0 to ∼0.6 wt. % caused a sharp decrease in the aspect ratio of the aligned Au7Ga2rectangular particles; a change from 3 to 12 wt. % Ge caused a change from a GaAs‐rich matrix to a Au‐rich matrix with the appearance of characteristically shaped AuGeAs patches.

ISSN:0734-211X    

DOI:10.1116/1.583565

出版商:American Vacuum Society    

年代:1986

数据来源: AIP

摘要:

We have demonstrated a new type of GaAs/AlGaAs charge‐coupled device (CCD) in which the charge is confined to a quantum‐well channel. The MBE‐grown quantum‐well CCD (designated QWCCD) has a channel consisting of a 140 Å GaAs layer clad on both sides by AlGaAs layers. This structure was grown on a multiple‐quantum‐well (MQW) structure consisting of 60 periods of GaAs and AlGaAs layers of about 100 Å thickness each. Large optical modulation effects involving quantum‐confined excitons were observed in the MQW structure when a bias was applied perpendicular to the plane of the layers. The combination of QWCCD and MQW structures has promise as a high‐speed spatial light modulator for applications in optical signal processing.

ISSN:0734-211X    

DOI:10.1116/1.583562

出版商:American Vacuum Society    

年代:1986

数据来源: AIP

ISSN:0734-211X    

DOI:10.1116/1.583566

出版商:American Vacuum Society    

年代:1986

数据来源: AIP

ISSN:0734-211X    

DOI:10.1116/1.583567

出版商:American Vacuum Society    

年代:1986

数据来源: AIP