CN212062457U

CN212062457U - Graphical sapphire substrate

Info

Publication number: CN212062457U
Application number: CN202020967823.2U
Authority: CN
Inventors: 侯想; 钟梦洁; 刘杨; 蔡琦; 李思宏
Original assignee: Fujian Zoomking Technology Co ltd
Current assignee: Fujian Zoomking Technology Co ltd
Priority date: 2020-06-01
Filing date: 2020-06-01
Publication date: 2020-12-01
Anticipated expiration: 2030-06-01

Abstract

The utility model discloses a graphical sapphire substrate, which comprises a substrate made of sapphire material, wherein the size of the graph is 0.45-9.9um in bottom width and 0.3-10um in height; the substrate is conical and has an upward conical part, the substrate sequentially comprises a coating section, a middle section and a connecting section from the conical part to the bottom, the upper surface of the coating section is adhered with a coating made of aluminum nitride material and having a nano-scale thickness, and the coating is positioned above the middle section and suspended in the air to form a bridge shape; the substrates are distributed in a linear array, and grooves are formed between adjacent conical substrates and the film covering. The utility model discloses a graphical sapphire substrate can effectively promote LED light extraction efficiency, can reduce the meeting an emergency that leads to between sapphire and the GaN because of great lattice mismatch, has not only solved the epitaxial growth atomizing problem of GaN epitaxial material, makes the epitaxial growth volume reduce moreover, effectively shortens epitaxial growth time.

Description

Graphical sapphire substrate

Technical Field

The utility model relates to a LED lamp field especially relates to a graphical sapphire substrate.

Background

In recent years, the application of GaN-based materials in light-emitting devices and high-power devices has attracted people's attention, and sapphire as a substrate material of heteroepitaxial GaN has good physical properties and chemical properties, mature production technology, high mechanical strength and easy processing, and is one of the most widely applied materials of the heteroepitaxial GaN at present. However, due to the serious lattice mismatch and thermal expansion coefficient mismatch between the GaN material and the sapphire substrate, a large amount of linear dislocation density is generated inside the epitaxial material, and the internal quantum efficiency of the GaN-based LED device is greatly influenced.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving the defects existing in the prior art, and provides a graphical sapphire substrate.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a patterned sapphire substrate comprises a substrate made of sapphire material, wherein the pattern size is 0.45-9.9um in bottom width and 0.3-10um in height; the substrate is conical and has an upward conical part, the substrate sequentially comprises a coating section, a middle section and a connecting section from the conical part to the bottom, the upper surface of the coating section is adhered with a coating made of aluminum nitride material and having a nano-scale thickness, and the coating is positioned above the middle section and suspended in the air to form a bridge shape; the substrates are distributed in a linear array, and grooves are formed between adjacent conical substrates and the film covering.

Preferably, the thickness of the coating is in the range of 5nm to 1 μm.

Preferably, the substrate comprises a plurality of forms of array distribution according to different required forms.

Preferably, the substrate further comprises a connecting section located below the middle section, and the connecting sections are connected with each other in a plate shape.

Preferably, the groove is positioned above the connecting section, and the cross section of the groove is trapezoidal.

Preferably, the length of the top edge in the trapezoidal cross section of the groove is 0.05-2 μm.

Preferably, the coating comprises a conical groove connected with the coating section, and the groove depth of the conical groove is less than 8 μm.

The utility model has the advantages that: in the utility model, firstly, the large-size conical sapphire substrate is used, so that the duty ratio of the pattern is large, and the LED light extraction efficiency can be effectively improved; secondly, the sapphire substrate adopts an aluminum nitride material coated film, so that the strain between the sapphire and the GaN caused by larger lattice mismatch can be reduced; and thirdly, the ALN film is coated to form a bridge type overhead layer between the sapphire patterns to limit the grooves, so that the problem of atomization of epitaxial growth of GaN epitaxial materials is solved, the epitaxial growth volume is reduced, and the epitaxial growth time is effectively shortened.

Drawings

Fig. 1 is a view of an inverted structure of a sapphire substrate according to the present invention;

fig. 2 is a front view of a sapphire substrate according to the present invention;

fig. 3 is a top view of a sapphire substrate according to the present invention;

FIG. 4 is a cross-sectional view taken along line A-A of FIG. 3;

fig. 5 is a schematic view of the epitaxial growth of the present invention.

Reference numbers in the figures: 1 substrate, 11 coating sections, 12 middle sections, 13 connecting sections, 2 coating films, 21 conical grooves and 3 grooves.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments.

Referring to fig. 1 to 5, wherein MQW in fig. 5 denotes a multiple quantum well material, ALN is an aluminum nitride material, PSS is a large-sized sapphire, a patterned sapphire substrate comprising a substrate 1 using a sapphire material and having a pattern size of 0.45 to 9.9um in bottom width and 0.3 to 10um in height; the substrate 1 is conical and has an upward conical part, the substrate 1 sequentially comprises a coating section 11, a middle section 12 and a connecting section 13 from the conical part to the bottom, the upper surface of the coating section 11 is adhered with a coating 2 made of aluminum nitride material and having a nanometer-scale thickness, and the coating 2 is positioned above the middle section 12 and suspended in the air to form a bridge shape; the substrates 1 are distributed in a linear array, and a groove 3 is arranged between the adjacent conical substrates 1 and the covering film 2.

The thickness of the coating 2 is in the range of 5nm to 1 μm.

The substrate 1 includes a plurality of types of array distribution according to the required type.

The substrate 1 further comprises coupling sections 13 located below the middle section 1, the coupling sections 13 being connected to each other in a plate shape.

The groove 3 is positioned above the connecting section 13, and the cross section of the groove 3 is trapezoidal.

The length of the top edge in the trapezoidal cross section of the groove 3 is 0.05-2 μm.

The coating 2 comprises a conical groove 21 connected to the coating section 11, the conical groove 21 having a groove depth of less than 8 μm.

The working principle is as follows: the patterned sapphire substrate is also called PSS, and the special periodic micro-patterned surface structure of the PSS can enhance the scattering of light between the GaN and the substrate interface, improve the probability of light emergent from the inside of the active layer and further increase the light extraction efficiency. Because the conical substrate 1 forms a structure similar to a micro lens, the emergent angle of light is improved, the internal reflection of the light in the LED is enhanced, and the light escape efficiency is improved. With the same PSS, as the duty ratio is increased, the LED light output power is increased, and the reflection of the reflected light from the active layer is increased. The large-size sapphire substrate (with the bottom width of 0.45-9.9um and the height of 0.3-10 um) has better refractive index, and can improve the output power of the LED lamp. Research shows that the graph duty ratio and the LED light extraction efficiency are in a parabolic relation, and within a certain range, the light extraction efficiency is increased along with the increase of the graph duty ratio and starts to be in a descending trend after reaching an upper limit value; the duty cycle, also known as the fill factor, refers to the proportion of the effective microstructures per unit area, and is related to the shape of the base and the spacing between adjacent microstructures. Therefore, the utility model discloses further provide the range of 3 groove bottoms of recess width and the groove depth of circular cone groove 21, promote the light extraction efficiency of LED lamp.

The main materials of the common patterned sapphire substrate are Al2O3, the lattice mismatch between Al2O3 and GaN material is large, and the atomization phenomenon is easy to occur when GaN is epitaxially grown due to the large pattern duty ratio and the small adjacent pattern spacing of the large-size PSS. The utility model discloses a AlN tectorial membrane can reduce the meeting an emergency that leads to because of great lattice mismatch between sapphire and the GaN, be favorable to epitaxial growth to there is one section sky layer between AlN tectorial membrane and the conical figure of sapphire, GaN epitaxial growth is upwards grown by AlN tectorial membrane layer, not only limits the groove volume, can effectively reduce GaN epitaxial growth time, and the interval on adjacent conical AlN tectorial membrane layer is bigger than the conical figure interval of Al2O3, more is favorable to improving atomization phenomenon.

The utility model discloses combine the excellent characteristic of AlN material (being the aluminium nitride material), and the problem that jumbo size PSS exists, combine the two, consider to make the special AlN film of one deck as tectorial membrane 2 on jumbo size PSS, utilize the photoresist to block earlier, hold out recess 3, then do one deck AlN tectorial membrane on conical tectorial membrane section and photoresist upper surface, reuse ultrasonic cleaning and get rid of the photoresist in the recess 3, let tectorial membrane 2 present unsettled bridge form, directly upwards grow by the tectorial membrane layer during epitaxial growth. Therefore, the problems of epitaxial atomization and dislocation caused by large PSS size are solved, the growth of epitaxial GaN is facilitated, and the epitaxial growth time is shortened. The utility model discloses an array distribution constitute the foundation structure of sapphire substrate, consequently adopt linear array distribution and other array distribution's sapphire substrate, as long as constitute the utility model's foundation structure, also all should the utility model discloses an in the protection scope.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and to simplify the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically limited otherwise.

The above, only be the concrete implementation of the preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art is in the technical scope of the present invention, according to the technical solution of the present invention and the utility model, the concept of which is equivalent to replace or change, should be covered within the protection scope of the present invention.

Claims

1. A patterned sapphire substrate is characterized by comprising a conical substrate (1) which is made of a sapphire material and has the pattern size of 0.45-9.9um bottom width and 0.3-10um height; the substrate (1) is conical and has an upward conical part, the substrate (1) sequentially comprises a coating section (11), a middle section (12) and a connecting section (13) from the conical part to the bottom, the upper surface of the coating section (11) is adhered with a coating (2) made of aluminum nitride material and having a nanometer thickness, and the coating (2) is positioned above the middle section (12) and is suspended in the air to form a bridge shape; the substrate (1) is provided with a plurality of substrates which are distributed in an array, and a groove (3) is arranged between the adjacent conical substrate (1) and the coating film (2).

2. A patterned sapphire substrate according to claim 1, wherein the thickness of the cover film (2) is in the range 5nm-1 μm.

3. A patterned sapphire substrate according to claim 1, wherein the substrate (1) comprises a plurality of patterns of array distribution according to different required patterns.

4. A patterned sapphire substrate according to claim 1, wherein the substrate (1) further comprises connecting segments (13) located below the middle segment (12), the connecting segments (13) being connected to each other in a plate shape.

5. A patterned sapphire substrate according to claim 4, wherein the recess (3) is located above the junction (13) and the cross-section of the recess (3) is trapezoidal.

6. A patterned sapphire substrate according to claim 5, wherein the top side of the trapezoidal cross-section of the recess (3) has a length of 0.05-2 μm.

7. A patterned sapphire substrate according to claim 1, wherein the coating (2) comprises conical grooves (21) connected to the coating segments (11), the grooves (21) having a groove depth of less than 8 μm.