Answer:
=> base transport factor = 0.98.
=> emitter injection efficiency = 0.99.
=> common-base current gain = 0.97.
=> common-emitter current gain = 32.34.
=> ICBO = 1 × 10^-6 A.
=> base transit time = 0.325.
=> lifetime = 1.875.
Explanation:
(Kindly check the attachment for the diagram showing the dominant current components, with proper arrows, for directions in the normal active mode).
The following parameters or data are given for a p-n-p BJT with NE 7 NB 7 NC and they are: IEp = 10 mA, IEn = 100 mA, ICp = 9.8 mA, and ICn = 1 mA.
(1). The base transport factor = ICp/IEp=9.8/10 = 0.98.
(2). emitter injection efficiency =IEp/ IEp + ICn = 10/10 + 0.1 = 0.99.
(3).common-base current gain = 0.98 × 0.99 = 0.9702.
(4).common-emitter current gain =0.97 / 1- 0.97 = 32.34.
(5). Icbo = Ico = 1 × 10^-6 A.
(6). base transit time = 1248 × 10^-2 × (1.38× 10^-23/1.603 × 10^-19). = 0.325.
(7).lifetime;
= > 2 = √0.325 + √ lifetime.
= Lifetime = 2.875.