US-12616997-B2 - Electronic device including a transducer electrically connected to a demultiplexer and method for fabricating the transducer in the electronic device

US12616997B2US 12616997 B2US12616997 B2US 12616997B2US-12616997-B2

Abstract

An electronic device is provided. The electronic device includes multiple transducer pixels. Each of the transducer pixels includes a sonic transducer, a demultiplexer electrically connected to the sonic transducer, a driving line electrically connected to the sonic transducer, a switching line electrically connected to the demultiplexer, and a reading line electrically connected to the demultiplexer. The driving line is used to provide a driving signal to the sonic transducer to emit sonic waves. The switching line is used to turn on the demultiplexer to output the sensing signal received by the sonic transducer to the reading line.

Inventors

Wei-Lin WAN
Yu-Tsung Liu
Hui-Ching Yang
Te-Yu Lee

Assignees

Innolux Corporation

Dates

Publication Date: 20260505
Application Date: 20211209
Priority Date: 20210125

Claims (7)

1 . An electronic device, comprising: a plurality of transducer pixels, each transducer pixel comprises: a sonic transducer; a first demultiplexer electrically connected to the sonic transducer; a driving line electrically connected to the sonic transducer; a switching line electrically connected to the first demultiplexer; a reading line electrically connected to the first demultiplexer, wherein the driving line is used to provide a driving signal to the sonic transducer to emit sonic waves, and the switching line is used to turn on the first demultiplexer to output a sensing signal received by the sonic transducer to the reading line; and a driving circuit electrically connected to a second demultiplexer, wherein the second demultiplexer comprises at least two transistors having source electrodes used to receive a driving signal and a reference signal respectively.
2 . The electronic device as claimed in claim 1 , wherein the first demultiplexer comprises at least two transistors having gate electrodes, and the switching line comprises two branch lines electrically connected to the gate electrodes of the at least two transistors.
3 . The electronic device as claimed in claim 1 , wherein the sonic transducer comprises a piezoelectric micromachined ultrasonic transducer (PMUT).
4 . The electronic device as claimed in claim 3 , wherein the PMUT comprises a lower electrode, a piezoelectric layer and an upper electrode, and the piezoelectric layer is between the upper electrode and the lower electrode.
5 . The electronic device as claimed in claim 4 , further comprising a cavity in an insulating layer below the lower electrode.
6 . The electronic device as claimed in claim 1 , wherein the sonic transducer comprises a capacitive micromachined ultrasonic transducer (CMUT).
7 . The electronic device as claimed in claim 6 , wherein the CMUT comprises a lower electrode, an insulating layer, a cavity and an upper electrode, and the cavity is in the insulating layer between the lower electrode and the upper electrode.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application claims priority of China Patent Application No. 202110095049.X, filed on Jan. 25, 2021, the entirety of which is incorporated by reference herein. BACKGROUND Technical Field The present disclosure relates to an electronic device, and in particular it relates to a sonic transducer and a method for fabricating the same. Description of the Related Art The core component of the sonic-wave sensing system is, for example, a micromachined ultrasonic transducer (MUT), which is currently one of the focuses of active development in the industry. So far, most MUTs are based on passive matrices and are fabricated on wafers. Three-dimensional array images cannot be realized. The MUT and external circuits need to be integrated by wafer bonding, which is costly and difficult to fabricate a large-area MUT. Therefore, how to reduce costs and/or realize large-area production is what the industry expects. SUMMARY In accordance with one embodiment of the present disclosure, an electronic device is provided. The electronic device includes multiple transducer pixels. Each transducer pixel includes a sonic transducer, a demultiplexer electrically connected to the sonic transducer, a driving line electrically connected to the sonic transducer, a switching line electrically connected to the demultiplexer, and a reading line electrically connected to the demultiplexer. The driving line is used to provide a driving signal to the sonic transducer to emit sonic waves. The switching line is used to turn on the demultiplexer to output the sensing signal received by the sonic transducer to the reading line. In accordance with one embodiment of the present disclosure, a method for fabricating a sonic transducer is provided. The fabrication method includes providing a substrate, forming a driving layer on the substrate, forming a sacrificial layer on the driving layer, forming a piezoelectric layer on the sacrificial layer, and etching the sacrificial layer, wherein the step of etching the sacrificial layer is performed before forming the piezoelectric layer. In accordance with one embodiment of the present disclosure, a method for fabricating a sonic transducer is provided. The fabrication method includes providing a substrate, forming a driving layer on the substrate, forming a lower electrode on the driving layer, forming a sacrificial layer on the lower electrode, forming an upper electrode on the sacrificial layer, and removing the sacrificial layer. A detailed description is given in the following embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The disclosure may be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein: FIG. 1 is a circuit diagram of an electronic device in accordance with one embodiment of the present disclosure; FIG. 2-1 is a circuit diagram in an electronic device in accordance with one embodiment of the present disclosure; FIG. 2-2 is a circuit diagram in an electronic device in accordance with one embodiment of the present disclosure; FIG. 3-1 shows a top view of a sonic transducer in accordance with one embodiment of the present disclosure; FIG. 3-2 shows a schematic cross-sectional view taken along the cross-sectional lines A-A′ and B-B′ of FIG. 3-1 in accordance with one embodiment of the present disclosure; FIG. 3-3 shows a schematic cross-sectional view of a method for fabricating a sonic transducer in accordance with one embodiment of the present disclosure; FIG. 4-1 shows a top view of a sonic transducer in accordance with one embodiment of the present disclosure; FIG. 4-2 shows a schematic cross-sectional view taken along the cross-sectional lines A-A′ and B-B′ of FIG. 4-1 in accordance with one embodiment of the present disclosure; FIG. 4-3 shows a schematic cross-sectional view of a method for fabricating a sonic transducer in accordance with one embodiment of the present disclosure; and FIG. 4-3-2 shows a schematic cross-sectional view of a method for fabricating a sonic transducer in accordance with one embodiment of the present disclosure. DETAILED DESCRIPTION Various embodiments or examples are provided in the following description to implement different features of the present disclosure. The elements and arrangement described in the following specific examples are merely provided for introducing the present disclosure and serve as examples without limiting the scope of the present disclosure. For example, when a first component is referred to as “on a second component”, it may directly contact the second component, or there may be other components in between, and the first component and the second component do not come in direct contact with one another. In addition, when the terms “comprising”, “including” and/or “having” are used in the description of the present disclosure, they specify the corresponding featur