ZIB

Treffer pro Seite

Treffer 1 - 2 | 2 Treffer

Sortierung

Digitale Medien

Surface passivation effects of As2S3 glass on self-aligned AlGaAs/GaAs heterojunction bipolar transistors (1990)

Chuang, H. L. ; Carpenter, M. S. ; Melloch, M. R. ; [weitere]

Woodbury, NY : American Institute of Physics (AIP)

Applied Physics Letters 57 (1990), S. 2113-2115

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1077-3118

Quelle: AIP Digital Archive

Thema: Physik

Notizen: A recently developed As2S3 chemical treatment was used to passivate the perimeters of self-aligned heterojunction bipolar transistors (HBTs). The As2S3 chemical treatment significantly lowered the base current resulting in a two order of magnitude reduction in the collector current density at which dc current gain was observed (β=1). No degradation with time has been observed in the electrical characteristics of the chemically treated HBTs. This absence of degradation is attributed to the impermeability to oxygen of the As2S3 glass which coats the perimeter of the HBT after chemical treatment.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.104114

Permalink

Bibliothek	Standort	Signatur	Band/Heft/Jahr	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

Digitale Medien

On-line state estimation and control in glutamic acid production (1991)

Tsao, J. -H. ; Chuang, H. -L. ; Wu, W. -T.

Springer

Bioprocess and biosystems engineering 7 (1991), S. 35-39

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1432-0797

Quelle: Springer Online Journal Archives 1860-2000

Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung

Notizen: Abstract An automatic computer control system for glutamic acid production has been developed. A method based on empirical reaction subspace and singular value decomposition was presented for on-line estimation of cell concentration, glutamic acid, and total sugar. The only on-line measured state variable was the oxygen uptake rate. The estimated cell concentration was used as an index for the addition of penicillin. The estimated total sugar concentration was used for system identification. Adaptive control was then applied to manipulate the substrate feeding rate. The total sugar concentration was maintained at a given value during the period of fed-batch culture for glutamic acid production.