Masters Theses


"The investigation of electric field strength dependence of the rate of damage introduction, caused by gamma and neutron irradiations in matched is reported. Groups of devices (with varying biases applied to the emitter-base and collector-base junctions to allow study of the electric field strength dependence) were exposed to ionizing gamma radiation from a Co-60 source. Similar experiments were conducted to study the field strength dependence of the rate of space-charge volume damage introduction, caused by fast neutrons (E> l0keV, fission source). The experimental results indicate that the rate of surface degradation, as reflected by the increase of the normalized surface base current component (ΔI/IB(0)) and the reciprocal of the surface minority carrier lifetime is an increasing function of the electric field strength and the total gamma dose (1x10⁴ rads (Si) < Δ < 1x10⁶ rads (Si)). The ionizing gamma induced surface effects are significant at low fluences in the swimming pool type reactor and have to be subtracted from the total variation in transistor parameters (junction capacitance and base current component) before a meaningful interpretation of the fast neutron induced bulk effects can be given. The rate of volume damage introduction, Kv, was investigated in an effort to explain the anomalous behavior of fast neutron induced defect clusters in the high field space charge region of silicon p-n junctions. Kv is observed to be an increasing function of the average electric field strength in the p-n junction during irradiation and a decreasing function of the neutron fluence. Empirical expressions for the surface degradation and rate of volume damage introduction are developed"--Abstract, page ii.


Goben, C. A.

Committee Member(s)

Bolon, Albert E., 1939-2006
Hardtke, Fred C.


Nuclear Engineering and Radiation Science

Degree Name

M.S. in Nuclear Engineering


U.S. Atomic Energy Commission


University of Missouri--Rolla

Publication Date



viii, 61 pages, 54 pages

Note about bibliography

Includes bibliographical references (page 34).


© 1970 Cyrus Hoshang Irani, All rights reserved.

Document Type

Thesis - Open Access

File Type




Subject Headings

Electric fields -- Measurement
Energy dissipation
Gamma rays

Thesis Number

T 2431

Print OCLC #


Electronic OCLC #