Infrared imaging element, infrared imaging array, and method for manufacturing infrared imaging element
AssigneeMitsubishi Electric Corporation
InventorTomohiro Maegawa
Life of this patent
Estimating the term…
Abstract
This infrared imaging element includes: a substrate which has a front surface and a back surface and to which a circuit unit is provided; a support leg wiring line that is disposed above the front surface of the substrate; and an infrared-ray detection unit which is held on the support leg wiring line and to which a diode electrically connected to the circuit unit via the support leg wiring line is provided, wherein the temperature change of the infrared-ray detection unit is detected as an electrical signal change of the diode by the circuit unit. The substrate, the support leg wiring line, and the infrared-ray detection unit are laminated at intervals in a direction perpendicular to the front surface of the substrate.
Claims8
An infrared imaging element, comprising:
- a first substrate, comprising:
- a supporting leg wiring;
- a metal layer provided on the supporting leg wiring;
- and
- an infrared detection part held on the supporting leg wiring and provided with a diode electrically connected to the metal layer through the supporting leg wiring, and
- a second substrate, comprising:
- a substrate having a front surface and a back surface and provided with a circuit part;
- and
- a metal layer formed on the front surface of the substrate,
- the first substrate being bonded to the second substrate so that the metal layer is connected to the metal layer, and
- the infrared imaging element detecting a temperature change of the infrared detection part as a change of an electrical signal of the diode by the circuit part, wherein
- the substrate, the supporting leg wiring, and the infrared detection part are stacked in a direction Z perpendicular to the front surface of the substrate at an interval therebetween,
- the supporting leg wiring has one end connected to the metal layer which is formed on the metal layer provided on the surface of the substrate and to be a micro bump and another end connected to a metal wiring provided on the infrared detection part,
- the metal wiring, which is not electrically connected to the supporting leg wiring, is also provided immediately above the supporting leg wiring connected to the metal layer, and a micro bump bonding strength reinforcing beam having the same structure as the infrared detecting part, formed of a BOX oxide film and a dielectric film separated from the infrared detecting part, and increasing the bonding strength of the micro bump.
A method for manufacturing an infrared imaging element, comprising:
- a step of preparing a first substrate, the step including the steps of,
- preparing a SOI substrate having a BOX oxide film and a silicon layer on a substrate:
- processing the silicon layer to form a diode,
- after forming an insulating film on the BOX oxide film, opening the insulating film to expose the surface of the diode, and forming a first metal wiring connected to the diode and a second metal wiring on a part of the insulating film,
- forming a sacrificial layer on the BOX oxide film,
- forming a supporting leg wiring having an end connected to the first metal wiring on the sacrificial layer, and
- forming a first metal layer on the supporting leg wiring immediately above the second metal wiring formed on the insulating film, so that another end of the supporting leg wiring is connected to the first metal layer,
- a step of preparing a second substrate, the step including the steps of,
- preparing a substrate having a front surface and a back surface,
- forming a circuit part on a front surface side of the substrate, and
- forming a second metal layer electrically connected to the circuit part,
- a step of bonding the first metal layer and the second metal layer such that the front surfaces of the first substrate and the second substrate face each other;
- a step of removing the substrate from a back surface side to expose the BOX oxide film;
- a step of removing the sacrificial layer;
- and
- a step of partially removing the BOX oxide film and the insulating film to form a micro bump bonding strength reinforcing beam, having the same structure as the infrared detecting part and separated from the infrared detecting part, on the second metal wiring above and connected to the first metal layer through the supporting leg wiring.
Dependencies are inferred from the claim text.