FIELD

The improvements generally relate to the field of printed electronic devices and more specifically relate to control such printed electronic devices.

BACKGROUND

Printed electronic devices are typically made from substrates on which electronic circuits are printed. As can be understood, printing of an electronic device generally involves depositing conductive ink on a substrate in a predetermined pattern to form conductive traces. The printing of such electronic circuits can be performed using conventional printing techniques suitable for defining patterns on substrates, such as screen printing, flexography, gravure, offset lithography, inkjet, sintering and the like. Printed electronic techniques enable for low-cost fabrication and large-volume production of electronic devices for applications such as flexible displays to name only one example.

As with any other production process, testing of some or all of the electronic devices during the production process is key in achieving a satisfactory production process. For instance, if the conductivity of the ink used in the printing technique varies below a given conductivity threshold over time, the operability of the resulting printed electronic devices could be negatively affected. As such, one technique to test the conductivity of the ink of a printed electronic device involves contacting measurement probes on the conductive traces to make a direct conductivity measurement at some point in the production process. However, such a testing technique can provide conductivity measurements which are limited in resolution. Moreover, this testing technique requires a physical contact of the traces, which can cause irreparable damage to the printed electronic device in at least some situations.

Although existing testing techniques are satisfactory to a certain degree, there remains room for improvement, especially in providing printed electronic device testing systems and methods which alleviate at least some of the above-mentioned drawbacks.

SUMMARY

In accordance with a first embodiment of the present disclosure, there is provided an electronic device testing system for testing an electronic device having a substrate on which a metamaterial structure is printed using an ink, the electronic device testing system comprising: a terahertz radiation emitter configured to emit an incident terahertz radiation beam to be incident on the metamaterial structure of the substrate, the incident terahertz radiation beam having power at least at the terahertz resonance frequency of the metamaterial structure; a terahertz radiation receiver configured to receive an outgoing terahertz radiation beam outgoing from the metamaterial structure and to measure an amplitude of an electric field of the outgoing terahertz radiation beam at least at the terahertz resonance frequency; and a controller configured to determine a conductivity value indicative of a conductivity of the ink based on said amplitude of the electric field of the outgoing terahertz radiation beam. In some embodiments, the controller can also be configured to generate a signal indicative of an action to be performed when the determined conductivity of the ink is below a given conductivity threshold.

Further in accordance with the first embodiment, the terahertz radiation emitter is for example a broadband terahertz radiation emitter, the terahertz radiation receiver being configured to measure a spectral power distribution of the outgoing terahertz radiation beam, the system further comprising a broadband terahertz radiation reference receiver configured to measure a spectral power distribution of a portion of the incident terahertz radiation beam, the controller being configured to determine the conductivity value based on the spectral power distribution of the incident terahertz radiation beam and on the spectral power distribution of the outgoing terahertz radiation beam.

Still further in accordance with the first embodiment, the terahertz radiation emitter is for example a broadband terahertz radiation emitter, the terahertz radiation receiver being configured to measure a spectral power distribution of the outgoing terahertz radiation beam, the controller being configured to determine the conductivity value based on an amplitude of a first spectral region including the terahertz resonance frequency and on an amplitude of a second spectral region being spectrally spaced-apart from the first spectral region.

Still further in accordance with the first embodiment, the metamaterial structure is for example provided in the form of a vortex phase plate.

Still further in accordance with the first embodiment, the terahertz radiation receiver is for example a terahertz radiation image receiver, the controller being configured to determine the conductivity value based on an amplitude of the electric field of the outgoing terahertz radiation beam at a central region thereof.

Still further in accordance with the first embodiment, the terahertz radiation emitter and the terahertz radiation receiver are for example complementary metal-oxide-semiconductor devices, the electronic device testing system being portable.

In accordance with a second embodiment of the present disclosure, there is provided an electronic device production system comprising: an electronic device printing system configured to print an electronic device including receiving a substrate, printing an electronic circuit on a given area of the substrate using an ink and printing a metamaterial structure on a remaining area of the substrate using the ink, the metamaterial structure comprising a pattern of elements providing a resonance at a terahertz frequency (hereinafter “the terahertz resonance frequency”) to the metamaterial structure; and an electronic device testing system being adapted to receive the previously printed substrate, the electronic device testing system comprising a terahertz radiation emitter configured to emit an incident terahertz radiation beam to be incident on the metamaterial structure of the substrate, the incident terahertz radiation beam having power at least at the terahertz resonance frequency of the metamaterial structure, a terahertz radiation receiver configured to receive an outgoing terahertz radiation beam outgoing from the metamaterial structure and to measure an amplitude of an electric field of the outgoing terahertz radiation beam at least at the terahertz resonance frequency; and a controller configured to determine a conductivity value indicative of a conductivity of the ink based on said amplitude and to generate a signal indicative of an action to be performed when the determined conductivity of the ink is below a given conductivity threshold.

Further in accordance with the second embodiment, said action includes for example generating a file indicating that the electronic device has been printed with ink having a conductivity value being below the given conductivity threshold.

Still further in accordance with the second embodiment, said action includes for example modifying at least one printing parameter of said electronic device printing system.

Still further in accordance with the second embodiment, said action includes for example one of partially and wholly reprinting the electronic circuit of the electronic device after said modifying.

In accordance with a third embodiment of the present disclosure, there is provided a method for testing an electronic device having an electronic circuit being printed on a given area of a substrate using an ink and a metamaterial structure being printed on a remaining area of the substrate, the metamaterial structure comprising a pattern of elements providing a terahertz resonance frequency to the metamaterial structure using the ink, the method comprising: emitting a terahertz radiation emitter incident on the metamaterial structure of the substrate, the incident terahertz radiation beam having power at least at the terahertz resonance frequency of the metamaterial structure, thereby causing an outgoing terahertz radiation beam to be outgoing from the metamaterial structure; the metamaterial structure modifying a first spectral power distribution of the incident terahertz beam and thereby causing an outgoing terahertz radiation beam to have a second spectral power distribution being different from the first spectral power distribution; measuring an amplitude of an electric field of the outgoing terahertz radiation beam at least at the terahertz resonance frequency; and using a controller being communicatively coupled to at least the terahertz radiation receiver, determining a conductivity value indicative of a conductivity of the ink based on said amplitude.

Further in accordance with the third embodiment, the incident terahertz radiation beam for example is a broadband terahertz radiation beam, said measuring including measuring a spectral power distribution of the outgoing terahertz radiation beam, the method further comprising measuring a spectral power distribution of a portion of the incident terahertz radiation beam, said determining including determining the conductivity value based on the spectral power distribution of the incident terahertz radiation beam and on the spectral power distribution of the outgoing terahertz radiation beam.

Still further in accordance with the third embodiment, the terahertz radiation beam for example is a broadband terahertz radiation beam, said measuring including measuring a spectral power distribution of the outgoing terahertz radiation beam, said determining comprising determining the conductivity value based on an amplitude of a first spectral region including the terahertz resonance frequency and on an amplitude of a second spectral region being spectrally spaced-apart from the first spectral region.

Still further in accordance with the third embodiment, the metamaterial structure is for example provided in the form of a vortex phase plate, said measuring including measuring an image of the outgoing terahertz radiation beam, said determining comprising determining the conductivity value based on an amplitude of the electric field of the outgoing terahertz radiation beam at a central region thereof.

Still further in accordance with the third embodiment, upon determining that the conductivity value is lower than a conductivity value threshold, generating for example a signal indicative of an action to be performed.

Still further in accordance with the third embodiment, said action including for example generating a file indicating that the electronic device has been printed with unsatisfactory ink.

Still further in accordance with the third embodiment, upon determining that the conductivity value is lower than a conductivity value threshold, updating for example current printing parameters to updated printing parameters based on said determined conductivity value.

Still further in accordance with the third embodiment, reprinting for example the electronic circuit on the given area of the substrate based on said updated printing parameters. In some embodiments, the updated printing parameters are used to print subsequent electronic devices only. The electronic device printed with unsatisfactory ink need not be reprinted, as it may be discarded in at least some situations.

Still further in accordance with the third embodiment, printing for example the metamaterial structure on the remaining area of the substrate using the ink.

It will be understood that the expression “computer” as used herein is not to be interpreted in a limiting manner. It is rather used in a broad sense to generally refer to the combination of some form of one or more processing units and some form of memory system accessible by the processing unit(s). Similarly, the expression “controller” as used herein is not to be interpreted in a limiting manner but rather in a general sense of a device, or of a system having more than one device, performing the function(s) of controlling one or more devices such as an electronic device, for instance.

It will be understood that the various functions of a computer or of a controller can be performed by hardware or by a combination of both hardware and software. For example, hardware can include logic gates included as part of a silicon chip of the processor. Software can be in the form of data such as computer-readable instructions stored in the memory system. With respect to a computer, a controller, a processing unit, or a processor chip, the expression “configured to” relates to the presence of hardware or a combination of hardware and software which is operable to perform the associated functions.

The term “amplitude” is used broadly herein so as to encompass terms such as “intensity,” “irradiance” and the like.

Many further features and combinations thereof concerning the present improvements will appear to those skilled in the art following a reading of the instant disclosure.

