Display substrate comprising fingerprint recognition sensors, method for manufacturing the same, and display device
Embodiments of the present disclosure relate to a display substrate, a method for manufacturing the same, and a display device. The display substrate includes a substrate, a pixel definition layer for defining pixels on the substrate, the pixel definition layer including a plurality of inter-pixel portions located between adjacent pixels, and a fingerprint recognition sensor located in the inter-pixel portions.
1. A method for manufacturing a display substrate comprising:
providing a substrate;
forming a pixel definition layer for defining pixels on the substrate, wherein each pixel comprises a light emitting device; and
forming the light emitting devices on the substrate and in the pixel definition layer, the pixel definition layer comprising a plurality of inter-pixel portions located between adjacent light emitting devices,
wherein forming the pixel definition layer comprises forming a fingerprint recognition sensor in at least one of the inter-pixel portions, and
wherein the fingerprint recognition sensor is an ultrasonic fingerprint recognition sensor, wherein the ultrasonic fingerprint recognition sensor comprises a generator and a receiver, wherein forming the ultrasonic fingerprint recognition sensor comprises positioning the generator and the receiver in different inter-pixel portions, the inter-pixel portion comprising a first inter-pixel portion and a second inter-pixel portion located on opposite sides of each pixel, and wherein forming the first inter-pixel portion, the second inter-pixel portion, and the ultrasonic fingerprint recognition sensor comprises:
forming a first lower electrode in a region for forming the first inter-pixel portion on the substrate, and forming a second lower electrode in a region for forming the second inter-pixel portion on the substrate;
forming a first portion of the first inter-pixel portion covering the substrate and the first lower electrode in the region for forming the first inter-pixel portion, and forming a first portion of the second inter-pixel portion covering the substrate and the second lower electrode in the region for forming the second inter-pixel portion;
forming a first hole exposing the first lower electrode in the first portion of the first inter-pixel portion, and forming a second hole exposing the second lower electrode in the first portion of the second inter-pixel portion;
forming a first piezoelectric material in the first hole, and forming a second piezoelectric material in the second hole;
forming a first upper electrode on the first portion of the first inter-pixel portion and the first piezoelectric material, and forming a second upper electrode on the first portion of the second inter-pixel portion and the second piezoelectric material; and
forming a second portion of the first inter-pixel portion on the first upper electrode and the first portion of the first inter-pixel portion, and forming a second portion of the second inter-pixel portion on the second upper electrode and the first portion of the second inter-pixel portion.
2. The method according to claim 1 , wherein forming the first lower electrode and the second lower electrode comprises:
forming a first conductive layer on the substrate; and
patterning the first conductive layer to form the first lower electrode in the region for forming the first inter-pixel portion and to form the second lower electrode in the region for forming the second inter-pixel portion,
and wherein forming the first upper electrode and the second upper electrode comprises:
forming a second conductive layer covering the first portion of the first inter-pixel portion and the first piezoelectric material and covering the first portion of the second inter-pixel portion and the second piezoelectric material; and
patterning the second conductive layer to form the first upper electrode on the first portion of the first inter-pixel portion and the first piezoelectric material and to form the second upper electrode on the first portion of the second inter-pixel portion and the second piezoelectric material.
3. The method according to claim 2 , wherein forming each light emitting device comprises:
forming an anode on the substrate, wherein the anode is formed simultaneously with the first lower electrode and the second lower electrode;
forming a light emitting layer on the anode; and
forming a cathode on the light emitting layer and the pixel definition layer.
4. The method according to claim 3 , further comprising:
forming a TFT layer on the substrate before forming the pixel definition layer and the fingerprint recognition sensor;
forming a planarization layer on the TFT layer;
forming an encapsulation layer on the cathode after forming the cathode; and
forming a touch layer on the encapsulation layer.