Wafer-level testing of light-emitting resonant structures
A device for testing a light-emitting resonant structure on a wafer includes a vacuum chamber for holding the resonant structure; a source of charged particles; a electromagnetic radiation detector; a positioning mechanism constructed and adapted control the position of the wafer within the vacuum chamber; and a controller operatively connected to said source of electrons and to said detector and to said positioning mechanism. A voltage source may be provided.
1 . A device for testing a light-emitting resonant structure on a wafer, the wafer comprising a plurality of chips, at least one of said chips having one or more light emitting structures, the device comprising:
a vacuum chamber for holding the wafer;
a source of charged particles;
a detector; and
a controller operatively connected to each of the source of charged particles and the detector.
2 . A device as in claim 1 wherein the source of charged particles comprises a source of electrons.
3 . A device as in claim 1 wherein the detector is constructed and adapted to detect electromagnetic radiation.
4 . A device as in claim 3 wherein the electromagnetic radiation is visible light.
5 . A device as in claim 1 further comprising:
a positioning mechanism constructed and adapted control the position of the wafer within the vacuum chamber, the positioning mechanism being operatively connected to the controller.
6 . A device as in claim 1 further comprising:
a mechanism constructed and adapted to control the position of the source of charged particles relative to the wafer, the mechanism being operatively connected to the controller.
7 . A device as in claim 1 further comprising:
a mechanism constructed and adapted to vary a position of the detector relative to the wafer, the mechanism being operatively connected to the controller.
8 . A device as in claim 5 further comprising:
a mechanism constructed and adapted to control the position of the source of charged particles relative to the wafer, the mechanism being operatively connected to the controller.
9 . A device as in claim 1 further comprising:
a power source constructed and adapted to provide power to chips on the wafer, the power source being operatively connected to the controller.
10 . A device as in claim 9 wherein the power source is a low-voltage power source.
11 . A device for testing a light-emitting resonant structure on a wafer, the wafer comprising a plurality of chips, at least one of said chips having one or more light emitting structures, the device comprising:
a vacuum chamber for holding the resonant structure;
a source of electrons;
a electromagnetic radiation detector;
a positioning mechanism constructed and adapted control the position of the wafer within the vacuum chamber;
a controller operatively connected to said source of electrons and to said detector and to said positioning mechanism.
12 . A method of testing an electromagnetic radiation (EMR)-emitting structure on a wafer, said wafer comprising a plurality of chips, at least one of said chips having one or more light emitting structures, the method comprising:
(a) putting the wafer in a chamber and forming a vacuum within the chamber;
(b) positioning the wafer within the chamber so that an EMR-emitting structure on a particular chip of said plurality of chips to be tested is adjacent a path of a beam of charged particles;
(c) providing the beam of charged particles along the path; and
(d) attempting to detect EMR from said EMR-emitting structure.
13 . A method as in claim 12 further comprising:
repeating said steps (b) to (d) for at least one other EMR-emitting structure on said particular chip.
14 . A method as in claim 12 further comprising:
repeating steps (b) to (d) for at least one other chip on said wafer.
15 . A method as in claim 12 further comprising:
providing power to at least one chip on said wafer; and
attempting to detect EMR from at least one EMR-emitting structure on said chip.
16 . A method of testing a wafer, said wafer comprising a plurality of chips, at least one of said chips having one or more ultra-small structures constructed and adapted to emit electromagnetic radiation (EMR) in response to a beam of charged particles, the method comprising:
(a) putting the wafer in a chamber and forming a vacuum within the chamber;
(b) for a particular chip of said plurality of chips:
(b1) causing a beam of charged particles to be emitted adjacent at least one ultra-small structure on said particular chip; and
(b2) attempting to detect EMR from said at least one structure.
17 . A method as in claim 16 , wherein said beam of charged particles emitted in step (b2) is emitted from an off-chip particle source.
18 . A method as in claim 17 further comprising:
(c) positioning said particular chip within said chamber so that an EMR-emitting structure on said particular chip is adjacent a path of said beam of charged particles.
19 . A method as in claim 16 further comprising:
repeating step (b) for at least one other chip on said wafer.
20 . A method as in claim 16 further comprising:
repeating steps (b1) and (b2) for at least one other ultra-small structure on said particular chip.
21 . A method as in claim 16 , wherein said beam of charged particles emitted in step (b2) is emitted from an on-chip particle source, the method further comprising:
providing power to said particular chip.
22 . A method of testing a wafer, said wafer comprising a plurality of chips, at least one of said chips having one or more ultra-small structures constructed and adapted to emit electromagnetic radiation (EMR) in response to a beam of charged particles, the method comprising:
(a) putting the wafer in a chamber and forming a vacuum within the chamber;
(b1) causing a beam of charged particles to be emitted adjacent at least one ultra-small structure on at least one of said chips, said beam of charged particles being emitted by an off-chip particle source;
(b2) responsive to step (b1), attempting to detect EMR from said at least one structure;
(c1) causing another beam of charged particles to be emitted adjacent at least one ultra-small structure on at least one of said chips, said other beam of charged particles being emitted by an on-chip source of charged particles; and
(c2) responsive to step (c1), attempting to detect EMR from said at least one structure.
23 . A method as in claim 19 wherein said at least one structure in steps (b1) and (b2) is the same structure as in steps (c1) and (c2).
24 . A method of testing an electromagnetic radiation (EMR)-emitting structure on a wafer, said wafer comprising a plurality of chips, at least one of said chips having one or more light emitting structures, the method comprising:
(a) putting the wafer in a chamber and forming a vacuum within the chamber;
(b) causing the wafer to be positioned within the chamber so that an EMR-emitting structure on a particular chip of said plurality of chips to be tested is adjacent a path of a beam of charged particles;
(c) providing the beam of charged particles along the path; and
(d) attempting to detect EMR from said EMR-emitting structure.
25 . A method as in claim 24 wherein said step (b) comprises one or more of:
(b1) moving the wafer;
(b2) changing the path of the beam of charged particles.
26 . A method as in claim 25 wherein step (b2) comprises:
causing a source of the beam of charged particles to be moved.