Asset Details
Do you wish to reserve the book?
OPTICAL PROPERTIES OF DEEP LEVEL DEFECTS IN AMORPHOUS-GROWN AND IRRADIATED ZINC-SELENIDE
Hey, we have placed the reservation for you!
By the way, why not check out events that you can attend while you pick your title.
Oops! Something went wrong.
Looks like we were not able to place the reservation. Kindly try again later.
Are you sure you want to remove the book from the shelf?
OPTICAL PROPERTIES OF DEEP LEVEL DEFECTS IN AMORPHOUS-GROWN AND IRRADIATED ZINC-SELENIDE
Do you wish to request the book?
OPTICAL PROPERTIES OF DEEP LEVEL DEFECTS IN AMORPHOUS-GROWN AND IRRADIATED ZINC-SELENIDE
Please be aware that the book you have requested cannot be checked out. If you would like to checkout this book, you can reserve another copy
We have requested the book for you!
Your request is successful and it will be processed during the Library working hours. Please check the status of your request in My Requests.
Oops! Something went wrong.
Looks like we were not able to place your request. Kindly try again later.
Dissertation
OPTICAL PROPERTIES OF DEEP LEVEL DEFECTS IN AMORPHOUS-GROWN AND IRRADIATED ZINC-SELENIDE
1985
Overview
The optical and electrical properties of the deep-level defects present in as-grown and irradiated ZnSe were investigated to determine the compensation mechanisms that control the conductivity type in this material. Conductive ZnSe heteroepitaxial layers from 1 to 10 (mu)m thick were grown on n-GaAs using chemical vapor transport with hydrogen carrier gas. These layers were irradiated with 1.5 MeV electrons or protons at room temperature in order to enhance the concentration of native-defect-related states. Characterization of these layers was made by a combination of low-temperature photoluminescence, steady-state photocapacitance, and optically and electrically excited capacitance transient spectroscopy. The photoluminescence response of the as-grown ZnSe layers at 8 K showed deep emission at 1.94 and 2.2 eV, as well as donor-acceptor pair (DAP) emission at 2.681 eV. From an analysis of the bound exciton emission the residual acceptor responsible for the donor-acceptor pair emission was attributed to Na. Sodium has also been associated with hole traps at 90 and 130 meV above the valence band edge as measured by optical transient capacitance spectroscopy. The concentration of these two levels has been measured to be as high as 2 x 10('15) cm('-3), although the typical background concentration is less than 10('13) cm('-3). The low concentration of these levels indicates that shallow acceptor impurities are not important in compensating the as-grown material. The deep PL emission at 1.94 eV has been correlated with the appearance of an electronic level at E(,c)-2.25 eV as observed by steady-state photocapacitance. Electron irradiaton at 1.5 MeV enhanced the emission, consistent with its identification as the self-activated (zinc vacancy-donor) complex. Concentration measurements of the self-activated level by photocapacitance indicate that it, along with deep levels at E(,c)-1.1 and E(,c)-1.4 eV, is the dominant compensation center in the as-grown and electron irradiated ZnSe. In contrast, compensation in proton-irradiated ZnSe was found to occur from a center located at E(,c)-0.2 eV. This compensating center was found to anneal out between 260(DEGREES) and 300(DEGREES)C with an activation energy of 1.6 eV. Proton irradiation was also seen to introduce new trapping states at E(,c)-0.1, E(,v) + 0.15, E(,v) + 0.19, and E(,v) + 0.37 eV.
