US 5,688,698 AGranted

Method of fabricating a device having a wafer with integrated processing circuits thereon

AssigneeIowa State University Research Foundation, Inc.

InventorsDouglas S. Robinson, Terrence C. Jensen, Joseph N. Gray

Life of this patent

Estimating the term…

Loading patent…

Abstract

An integrated x-ray detection system includes an x-ray detector fabricated on a wafer with a housing for containing a gas. The detector has a plurality of microstrip anodes and the housing passes x-rays which partially ionize the gas thereby producing a pulse at one of the anodes. The same wafer also has a plurality of integrated active signal processing circuits which are respectively coupled to the anodes. Each active signal processing circuit receives and processes pulses from respective ones of the anodes and outputs a digital signal indicating the location and energy of x-rays detected by the detector. An isolation layer separates the x-ray detector from the active signal processing circuits.

Claims12

Dependent claims

A method for fabricating an integrated x-ray detection system, comprising the steps of:

integrating a plurality of active signal processing circuits into a wafer having a corresponding plurality of digital input/output contacts, said plurality of active signal processing circuits receiving pulses at a respective plurality of active signal inputs and processing said pulses to output digital information at said corresponding plurality of digital input/output contacts;
forming an isolating layer over said plurality of active signal processing circuits;
and
applying a polyimide layer over said wafer having a plurality of vias, said plurality of vias exposing said plurality of digital input/output contacts;
and
fabricating an x-ray detector over said wafer by metal deposition and application of insulating layers at temperatures sufficiently low such that said plurality of active signal processing circuits are not damaged, said x-ray detector having alternating potential strip and a plurality of anodes being electrically coupled to said plurality of active signal processing circuits, wherein said x-ray detector receives x-ray photons and outputs pluses at particular ones of said plurality of anodes closest to said x-ray photons, said active signal processing circuits processing said pulses and outputting digital information indicating locations and energies of said x-ray photons at said plurality of digital input/output contacts, wherein said isolating layer electrically isolates said x-ray detector from said plurality of signal processing circuits.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/475,331Filed 7 Jun 1995 · division
Priority: 31 Mar 1994
Granted: 18 Nov 1997
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

H10F 30/29
The devices having potential barriers, e.g. phototransistors: the devices being sensitive to radiation having very short wavelengths, e.g. X-rays,…
G01T 1/185
Measuring radiation intensity: with ionisation chamber arrangements
G01T 1/2935
Static instruments for imaging the distribution of radioactivity in one or two dimensions; Radio-isotope cameras: using ionisation detectors
H10F
Solar cells and light sensors