Reduced blooming devices
AssigneeRCA Corporation
InventorsEugene D. Savoye, Thomas W. Edwards, Lloyd F. Wallace
Life of this patent
Estimating the term…
Abstract
A target for vidicons and image intensifier tubes include a potential barrier less than about 1500 A from an input signal sensing surface. The targets also include various passivation means for stabilizing the energy level configuration along the input signal sensing surface by substantially fixing the valence or conduction band along that surface relative to the Fermi level.
Claims12
A charge storage device having a signal sensing element with an input signal sensing surface region and a charge storage region, and reading means for selectively contacting portions of said charge storage region, and sensing element comprising:
- (a) a single crystal semiconductor wafer having
- (1) a plurality of discrete storage regions along a second surface and extending into said wafer a distance less than the wafer thickness, said discrete regions being of a first conductivity type;
- (2) a bulk region in said wafer defined as a region extending between and bounded at opposite sides by said discrete regions and said signal sensing surface region;
- said bulk region being of a second conductivity type;
- (3) means for controlling blooming within said signal sensing surface region comprising a region of similar conductivity type to that associated with said bulk, and having a dopant concentration exceeding that of said bulk for controlling recombination of excess carriers, excited within localized regions of said bulk, at a first opposed surface of the wafer;
- said dopant concentration having a peak spaced from and located less than about 1500 A from said first surface of the wafer;
- (b) passivation means for stabilizing the energy levels along said first surface of the wafer;
- said means substantially fixing the energy level relationship of the conducting band of the minority carriers in the bulk relative to the Fermi energy level of the semiconductor wafer.
An imaging device comprising:
- a wafer of single crystal semiconductor material having a bulk region of one conductivity type, the wafer having a first surface with an input signal sensing region extending into the wafer along the first surface and a second surface with a plurality of charge storage regions extending into the wafer from the second surface, the wafer also having a potential barrier in the sensing region for controlling blooming, the potential barrier extending along the first surface, said barrier having a peak spaced from and located less than about 1500 A from the first surface;
- and
- means for passivating the energy levels of said wafer along the first surface so that the minority carrier conducting energy band level along the first surface is substantially fixed with respect to the Fermi energy level of the semiconductor material.
Dependencies are inferred from the claim text.