CN103094430B - Luminous structure - Google Patents

Abstract

An embodiment of the present invention provides a light-emitting structure, including a first semiconductor layer, a light-emitting layer, a second semiconductor layer, and a conductive material layer arranged in sequence, wherein the first semiconductor layer and the second semiconductor layer use different types of semiconductor material, the light emitting structure further includes an insulating layer, the insulating layer is located between the second semiconductor layer and the conductive material layer, so as to electrically insulate the second semiconductor layer from the conductive material layer. According to an embodiment of the present invention, a thin insulating layer is added between the second semiconductor layer and the conductive material layer, thereby electrically insulating the second semiconductor layer and the conductive material layer; avoiding direct contact between the conductive material layer and the semiconductor layer in the light emitting structure The resulting Schottky contact or ohmic contact reduces the forward series resistance in the light emitting structure, thereby improving the overall light extraction efficiency of the light emitting structure.

Description

a light-emitting structure

technical field

The invention belongs to the technical field of semiconductor manufacturing, and in particular relates to a light-emitting structure with quantum tunneling effect.

Background technique

GaN-based light-emitting diodes (LEDs) have the advantages of high brightness, low energy consumption, long life, and fast response. As a new type of high-efficiency solid-state light source, they are widely used in indoor lighting, landscape lighting, display screens, and signal indications. . When the positive pole of the power supply is connected to the positive pole of the LED, and the negative pole of the power supply is connected to the negative pole of the LED, the voltage at this time is a forward voltage. The forward voltage generally includes the sum of PN junction voltage, N-type GaN voltage, P-type GaN voltage and metal-semiconductor contact voltage.

Metal-semiconductor contact is a very important issue in the manufacture of semiconductor devices. Metal-semiconductor contact can be divided into two types: Schottky contact and ohmic contact. The contact condition directly affects the performance of the device. The resistance generated by Schottky contact or ohmic contact It will reduce the light extraction efficiency of the device.

Contents of the invention

In view of this, the purpose of the present invention is to provide a light-emitting structure with high light-extraction efficiency of the device.

To achieve the above object, an embodiment of the present invention provides a light emitting structure, including a first semiconductor layer, a light emitting layer, a second semiconductor layer and a conductive material layer arranged in sequence, wherein the first semiconductor layer and the second semiconductor layer Different types of semiconductor materials are used for the layers, and the light-emitting structure further includes an insulating layer, the insulating layer is located between the second semiconductor layer and the conductive material layer, so as to connect the second semiconductor layer and the conductive material layer layer of electrical insulation.

Preferably, the thickness of the insulating layer is not greater than 10 nm.

Preferably, the insulating layer is made of silicon oxide or silicon nitride.

Preferably, the conductive material layer is one or a combination of doped gallium nitride, doped silicon carbide, doped silicon, indium tin oxide, alloys or metals.

Preferably, the first semiconductor layer is made of N-type semiconductor material, and the second semiconductor layer is made of P-type semiconductor material.

Preferably, the light emitting structure further includes a first substrate, a first electrode and a second electrode, the first semiconductor layer is located between the first substrate and the light emitting layer, and the first electrode is located between the first substrate and the light emitting layer. The second electrode is located under the first semiconductor layer, and the second electrode is located on the conductive material layer.

Preferably, the first substrate is made of sapphire, gallium nitride, silicon carbide or silicon.

Preferably, the light emitting structure further includes a second substrate, a first electrode and a second electrode, the conductive material layer is located between the second substrate and the insulating layer, and the first electrode is located on the On the first semiconductor layer, the second electrode is located under the second substrate.

Preferably, the second substrate is made of an electrically and thermally conductive material.

Preferably, the first semiconductor layer uses a P-type semiconductor material, and the second semiconductor layer uses an N-type semiconductor material.

According to an embodiment of the present invention, a thin insulating layer is added between the second semiconductor layer and the conductive material layer, so as to electrically insulate the second semiconductor layer and the conductive material layer. Schottky contact or ohmic contact caused by direct contact between the conductive material layer and the semiconductor layer in the light-emitting structure is avoided, thereby reducing the forward series resistance in the light-emitting structure, thereby improving the overall light extraction efficiency of the light-emitting structure.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are For some embodiments of the present invention, those skilled in the art can also obtain other drawings based on these drawings without creative work.

FIG. 1 is a schematic structural view of a light emitting structure according to an embodiment of the present invention;

2 to 5 are structural schematic diagrams of the light emitting structure of Embodiment 1 of the present invention;

FIG. 6 is a schematic structural diagram of a light emitting structure according to Embodiment 2 of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In order to provide a light-emitting structure with high light extraction efficiency and avoid the resistance generated by the Schottky contact or ohmic contact in the light-emitting structure from reducing the light extraction efficiency of the device, the inventors of the present application propose the following technical solutions after research.

Embodiment one

1 shows a schematic structural view of a light emitting structure according to Embodiment 1 of the present invention, the light emitting structure includes a first semiconductor layer 101, a light emitting layer 102, a second semiconductor 103, an insulating layer 104 and a conductive material layer 105, wherein the first semiconductor The layer 101 can be made of N-type semiconductor material, the light-emitting layer 102 can be made of light-emitting materials commonly used in the art, the second semiconductor layer 103 can be made of P-type semiconductor material, and the insulating layer 104 can be made of silicon oxide or silicon nitride. The thickness can be no more than 10nm, such as 0.1nm, 0.5nm, 1nm, 2nm, 5nm, 10nm, etc. The actual thickness of the insulating layer 104 can be determined according to the design requirements, and the conductive material layer 105 can use commonly used conductive materials, such as doped doped gallium nitride, doped silicon carbide, doped silicon, indium tin oxide, metal or alloy, etc. In a specific embodiment, the conductive material layer 105 can be metal.

In the course of work, when the first semiconductor layer 101 in Fig. 1 adopts N-type semiconductor material, and the second semiconductor layer 103 adopts P-type semiconductor material, a positive voltage can be applied on the conductive material layer 105 side, and a positive voltage can be applied on the first semiconductor layer. Negative voltage is applied to one side of 101, specifically negative voltage and positive voltage can be applied through the first electrode 106 and the second electrode 107 (as shown in FIG. 2 ), wherein the specific shape and size of the first electrode 106 and the second electrode 107 can be determined according It depends on design requirements, and the present invention is not limited thereto. At this time, the carriers in the conductive material layer 105 move toward the first semiconductor layer (N-type semiconductor material layer) 101, but these carriers are blocked by the insulating layer 104 and cannot reach the second semiconductor layer (P-type semiconductor material layer). layer) 103. Continue to apply the positive voltage, the carriers blocked by the insulating layer 104 in the conductive material layer 105 accumulate to a certain amount, the majority carriers in the P-type semiconductor material layer 103 are depleted, and the minority carriers accumulate in the P-type semiconductor material layer 103 and the insulating layer 104, at this time, the carriers in the conductive material layer 105 can tunnel through the insulating layer 104 to reach the P-type semiconductor material layer 103, forming a tunneling current. In this way, the "P-type semiconductor material layer 103-insulating layer 104-conducting material layer 105" structure produces a quantum tunneling effect, and the work of the light emitting structure is neither based on Schottky contact nor ohmic contact, but based on quantum tunneling effect of tunneling current.

In the light emitting structure of Embodiment 1 of the present invention, a thin insulating layer 104 is added between the second semiconductor layer 103 and the conductive material layer 105 to electrically insulate the second semiconductor layer 103 and the conductive material layer 105 . Schottky contact or ohmic contact caused by direct contact between the conductive material layer and the semiconductor layer in the light-emitting structure is avoided, thereby reducing the forward series resistance in the light-emitting structure, thereby improving the overall light extraction efficiency of the light-emitting structure.

In addition, the light-emitting structure in Embodiment 1 of the present invention may further include a substrate 100, the substrate 100 is located on the N-type semiconductor material layer 101, and the N-type semiconductor material layer 101 is located between the substrate 100 and the light-emitting layer 102, As shown in FIG. 3 , the substrate 100 may be sapphire, gallium nitride, silicon carbide, or silicon. In addition, the light emitting structure shown in FIG. 3 may further include electrodes. FIG. 4 shows a schematic structural view thereof. The light emitting structure also includes a first electrode 106 and a second electrode 107, and the first electrode 106 is used to provide a negative voltage, and the second electrode 107 is used to provide a negative voltage. The two electrodes 107 are used to provide positive voltage. The N-type semiconductor material layer 101 forms a mesa, the first electrode 106 is located on a mesa on the N-type semiconductor material layer 101 , and the second electrode 107 is located on the conductive material layer 105 . Those skilled in the art can determine the shape and size of the first electrode 106 and the second electrode 107 as required, which is not limited in the present invention.

In addition, the light-emitting structure in Embodiment 1 of the present invention may further include a substrate 100'. As shown in FIG. , such as one or more of doped gallium nitride, doped silicon carbide, doped silicon, metal or alloy, at this time, the second electrode 107 on one side of the substrate 100' is used to connect Voltage, the first electrode 106 located on the other side of the first semiconductor layer (N-type semiconductor material) 101 is used to connect to a negative voltage.

The above describes the situation that the first semiconductor layer 101 uses an N-type semiconductor material, and the second semiconductor layer 103 uses a P-type semiconductor material. In the embodiment of the present invention, the first semiconductor layer 101 can also use a P-type semiconductor material, and the second semiconductor layer 103 may also use an N-type semiconductor material, which will be specifically introduced in Embodiment 2 below.

Embodiment two

The structure diagram of the light-emitting structure of the second embodiment of the present invention is shown in Figure 6. The difference from the first embodiment is that the first semiconductor layer 101 in the second embodiment uses a P-type semiconductor material, and the second semiconductor layer 103 uses a N-type semiconductor material. type semiconductor material. At this time, the insulating layer 104 is located between the N-type semiconductor material layer (second semiconductor layer) 103 and the conductive material layer 105, and the first electrode 106 located on the side of the first semiconductor layer (P-type semiconductor material layer) 101 is used to connect Positive voltage, the second electrode 107 on the other side of the conductive material layer 105 is used to connect to negative voltage.

The working principle of the light-emitting structure shown in Figure 6 is as follows: when a positive voltage is applied to the first electrode 106, the carriers in the P-type semiconductor material layer 101 move toward the direction of the conductive material layer 105, but these carriers are insulated The layer 104 prevents it from reaching the conductive material layer 105 , so it accumulates at the contact interface between the N-type semiconductor material layer 103 and the insulating layer 104 . Continue to apply a positive voltage to the first electrode 106, the carriers blocked by the insulating layer 104 in the P-type semiconductor material layer 101 accumulate to a certain amount, the majority carriers in the N-type semiconductor material layer 103 are depleted, and the minority carriers Accumulated at the contact interface between the N-type semiconductor material layer 103 and the insulating layer 104 , these carriers can tunnel through the insulating layer 104 to reach the conductive material layer 105 , forming a tunneling current. In this way, the "N-type semiconductor material layer 103-insulating layer 104-conducting material layer 105" structure produces a quantum tunneling effect, and the work of the light emitting structure is neither based on Schottky contact nor ohmic contact, but based on quantum tunneling effect of tunneling current.

It should be noted that the corresponding technical features in Embodiment 1 of the present invention can also be applied to Embodiment 2 of the present invention, and those of ordinary skill in the art can combine the technical solution of Embodiment 2 of the present invention with the It is easy for those skilled in the art to realize the corresponding technical features to obtain other technical solutions, and will not be repeated here.

The above is only a preferred embodiment of the present invention, it should be pointed out that, for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications can also be made. It should be regarded as the protection scope of the present invention.

Claims (6)

1. a ray structure, comprise the first semiconductor layer, luminescent layer, the second semiconductor layer and the conductive material layer of arranging successively, wherein said first semiconductor layer and described second semiconductor layer adopt dissimilar semi-conducting material, it is characterized in that, described ray structure also comprises insulating barrier, described insulating barrier between described second semiconductor layer and described conductive material layer, with by described second semiconductor layer and described conductive material layer electric insulation;

Wherein, described first semiconductor layer adopts P type semiconductor material, and described second semiconductor layer adopts N type semiconductor material;

Or described first semiconductor layer adopts N type semiconductor material, described second semiconductor layer adopts P type semiconductor material; When described ray structure also comprises the first substrate, the first electrode and the second electrode, described first semiconductor layer is between described first substrate and described luminescent layer, described first electrode is positioned on a table top on described first semiconductor layer, and described second electrode is positioned on conductive material layer; Or when described ray structure also comprises the second substrate, the first electrode and the second electrode, described conductive material layer is between described second substrate and described insulating barrier, described first electrode is positioned at described first semiconductor layer, and described second electrode is positioned under described second substrate.

2. ray structure according to claim 1, is characterized in that, the thickness of described insulating barrier is not more than 10nm.

3. ray structure according to claim 1, is characterized in that, described insulating barrier adopts silica or silicon nitride.

4. ray structure according to claim 1, is characterized in that, described conductive material layer adopts one or several the combination in the gallium nitride of doping, the carborundum of doping, the silicon of doping, tin indium oxide, alloy or metal.

5. ray structure according to claim 1, is characterized in that, described first substrate adopts sapphire, gallium nitride, carborundum or silicon.

6. ray structure according to claim 1, is characterized in that, described second substrate adopts conductive and heat-conductive material.