TW201029233A - Semiconductor light emitting element and method for manufacturing same - Google Patents

Abstract

A semiconductor light emitting element (10) includes: a substrate (11) having a surface which enables GaN crystal growth; a mask layer (12) having a surface which is arranged to cover the surface of the substrate (11) but has an opening (12a) where the surface of the substrate (11) is partially exposed and which disables GaN crystal growth; and a GaN layer (13) arranged to cover the mask layer (12) and the surface of the substrate (11) exposed through the opening (12a) of the mask layer (12). The mask layer (12) has a refraction index greater than that of SiO2 and smaller than that of the GaN layer (13).

Description

201029233 6. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to a semiconductor light-emitting element and a method of fabricating the same. [Prior Art] As a semiconductor light-emitting device such as a light-emitting diode (LED) or a semiconductor laser (LD), an element having a structure in which a semiconductor layer such as GaN is provided on a substrate has been mass-produced. Non-Patent Document 1 discloses a technique in which a mask layer made of Si〇2% is provided on a sapphire substrate, and a sapphire substrate is exposed in the mask layer to form a stripe-shaped groove, which is exposed from the groove. The sapphire substrate is a starting point for crystal growth of GaN, which is capable of reducing the defect (disi〇cati〇n), and by this, the light-emitting output power (external quantum efficiency) can be improved. Non-Patent Document 1 · K. Hoshino, T. Murata, M. Araki, and K. Tadatomo, phys. stat. sol. (c) 5, No. 9, 3060-3062 (2008) [Invention] The semiconductor light-emitting device includes a substrate having a surface on which GaN crystal can grow, a photomask layer provided to cover a surface of the substrate, and an opening in which a surface portion of the substrate is exposed and having a surface in which GaN crystal cannot grow And a GaN layer covering the surface of the photomask layer and the substrate exposed from the opening of the photomask layer; the refractive index of the photomask layer is greater than the refractive index of Si〇2 and smaller than the GaN layer Refractive index. A method of manufacturing a semiconductor light-emitting device according to the present invention is a method of manufacturing a semiconductor light-emitting device comprising: a substrate having a surface on which a GaN crystal can be elongated, and a photomask layer provided to cover the substrate a surface on which a surface portion of the substrate is exposed, a surface of the opening 3/22 201029233 having a GaN wire growth method, and a (10) layer covering the light monolayer and exposing from the opening of the photomask layer, Surface; deposited according to the αω method to form light! The layer layer is such that the refractive index of the photomask layer is greater than the refractive index of Si〇2 and smaller than the refractive index of the GaN layer. In the semiconductor light-emitting element, most of the light emitted by the limitation of the total reflection angle due to the difference in refractive index between the inside and the outside of the element is enclosed inside the element. In the case of a material light-emitting element, the substrate (for example, a sapphire substrate, a refractive index for light having a wavelength of 410 nm is (4) and a GaN layer grown thereon (refractive index of light for a wavelength of nm is 2) The limitation of the total reflection angle caused by the difference in refractive index of the five sentences, most of the emitted light is blocked by the GaN layer having a high refractive index. According to the present invention, the GaN layer is formed on the substrate by forming an opening in the photomask layer. - The side interface has a bump at (10) phase (4) its fine touch button reverse (four) at the interface reflection, and as a result, its light-portion is liberated from the limit of total reflection angle (10)alcan(4)(10)(4) without being enclosed in GaN The layer, and thus the number of layers, which are not enclosed in several parts, increases the probability of exiting to the outside of the component, and can be made high. And can be made such that the refractive index of the optical single layer is greater than the refractive index and smaller than the refractive index of the GaN layer. A high light extraction rate can be achieved. The GaN layer at a high refractive index causes propagtiated light to be partially refracted into the reticle layer and incident on the reticle layer. Light reflects or refracts at the interface of the soil Substrate-side. The ratio of this reflection and refraction depends on the refractive index of the mask layer. The refractive index of the mask layer is smaller than that of the substrate, and the ratio of the light in the human mask layer is enclosed in the mask layer. In the south, if the refractive index of the substrate becomes the same, the light incident into the mask layer will be efficiently emitted to the side of the substrate and out to the outside of the device. If the refractive index of the mask layer is greater than the refractive index of the substrate, The refractive index difference of the GaN layer is 4/22 201029233. The effect will be smaller, and the effect of reflecting or refracting the light of the mask layer itself will be smaller. And if the refractive index of the GaN layer becomes the same, it will not be for light. The present embodiment will be described in detail with reference to the accompanying drawings. (Semiconductor Light Emitting Element) FIG. 1 shows a semiconductor light emitting element 1A of the present embodiment. Embodiment 1 + related semiconductor light-emitting element 10, the surface of the substrate 11 is covered by the photomask layer 12, and sequentially stacked thereon with a u_GaN layer 13 (deliberately no impurity-added layer), n-type GaN | 14. Multiple quantum well layers 15, p Each of the semiconductor layers of the AlGaN layer 16 and the germanium type secret layer 17 is provided with a p-type electrode 19 on the p-type GaN layer π and an n-type on the n-type GaN layer 14 exposed by the insect. The electrode 18 is used as a light-emitting diode, etc. As the substrate 1 (4) 如 _ sapphire substrate (a single crystal substrate of a 〇 2 〇 3 diamond (C〇mndUm) structure), the other can also be Zn 〇 A substrate, an S1C substrate, etc. The substrate 1 is formed into a rectangular shape in a state of a light-emitting element, and has a thickness of 5 Å to 3 Å/m, respectively, in a vertical and horizontal direction. The surface of the substrate 11 is formed into a crystal of GaN. In the case of a sapphire substrate, the surface of the sapphire substrate can be a faceted (four) faceted surface. The face &lt;{_} face&gt;, the m-face <{l-ioow>, or the ^ face^b-face>, and may also be a crystal face of other face orientations. Further, the plane faces of the a face, the c face, and the melon face are perpendicular to each other. The refractive index of the substrate 11 is preferably larger than the refractive index of SiO 2 and smaller than the refractive index of the u-GaN layer 13 to be described later. Specifically, it is preferably M5 to 2.54, and L45 5/22 201029233 to 2·2 is more preferable. Here, the "refractive index" of the present invention is a value of light of 407 nm to 41 〇 nm with respect to the wavelength of the sapphire substrate of 1.76 〇 as a constituent material of the mask layer 12, for example, Nitrous oxide which cannot grow crystals of GaN (Si〇XNY: 〇&lt;x&lt;2, 〇&lt;Y&lt;4/3), oxidation = (:l〇i, yttrium aluminum oxide (A1Si〇), bismuth Boron _ 'boron nitride 矽 Ν 为) is the ideal cover layer 丨 2 thickness is preferably G.1~5.G / / m, G. 2 ~ 3, () _ then n cover layer 12 is formed with the substrate The opening of the surface portion of u is ri2a, for example, a groove, a hole, etc. The opening ❿ can be set to a plurality of 'specifically, for example, it is a structure in which the grooves are parallel to each other, or is made _ It is a lattice structure of vertical and horizontal, and the hole is located away from the ground. The domain is such that the groove is interposed between the grooves, and the direction of the groove can be extended from the surface of the substrate 11. The crystal composed of (10) cannot grow. 13 The refractive index of 2 is greater than (10) and less than the refractive index of layer u of (10) layer 13. Specifically, the refractive index of σ first layer 12 is greater than 1.45 and less than 2.54, 1.45. ~2 .2 is more desirable. The refractive index of the layer may be smaller than the refractive index of the substrate 11, the refractive index of 11 is opposite to the refractive index of the substrate 11 and may also be the refractive index with the substrate m. In the thick cover-layer 12, the refractive index in the thickness direction gradually decreases from the s-p soil side gradually, and the change becomes 201029233, and the Nb 2 t is unpredictable. And, the structure of the fresh layer 12 has a structure of peak change of one or even plural. ^ u The constituent material of the GaN layer 13 is non-inductive: „一__ is configured such that the substrate:= -aN heart can grow, on the other hand, make the surface of the light layer u

The crystal of = cannot grow. Therefore, the u-gayer layer 13 is formed by crystallizing from the surface (10) of the substrate (4) exposed from the opening 12a of the ^2. The thickness of the u-GaN germanium 13 is, for example, 2 to 2 Å. ...(10) Two women's branches of 2.5. Further, a low temperature buffer layer having a thickness of 2 〇 to 3 〇 nm left GaN is provided between the surface of the substrate ^ which is the starting point of the crystal growth and the u-GaN layer 13. As described above, according to the configuration of the mask layer 12 and the u_GaN layer 13, a portion of the GaN in the opening 12a formed in the mask layer 12 crystallizes in the normal direction of the surface of the substrate U to form a layer, and on the other hand, the opening is formed. The portion of the mask layer 12 other than the layer is crystallized and grown in the lateral direction via GaN to form a layer covering the portion. The difference in the defect density exhibited by the surface of the (1) (10) layer 13 by this will be lowered, and the external quantum efficiency can be improved. Moreover, in general, in a semiconductor light-emitting element, due to the limitation of the total reflection angle caused by the difference in refractive index between the inside and the outside of the element, most of the light of the light is enclosed in the element (10)', for example, having a bluestone substrate and In the case of the nitride semiconductor light-emitting element of the grown GaN layer, the cause of the total reflection angle caused by the difference in refractive index is limited, so that the light of the light-emitting 4 minute is enclosed in the 〇aN layer. However, as described above, according to the structure of the photomask layer 12 and the u-GaN layer 13, the interface on the substrate 11 side of the 12a'u-GaN layer 13 is formed in the photomask layer 12 by the opening 7/22 201029233. With irregularities, the light incident on the material plane of the u-GaN layer 13 is reflected by various reflection angles, and as a result, the portion of the light is liberated from the limitation of the total reflection angle, and is improved not to be enclosed inside the GaN layer, and thus not A high rate of light extraction can be obtained by the probability of being enclosed by the element and emerging outside the internal element. Further, the refractive index of the photomask layer 12 is larger than the refractive index of Si〇2 and smaller than the refractive index of the layer (~10), and a more remarkable effect can be obtained. In the case of the semiconductor light-emitting device 1 of the present embodiment,

The substrate 11 is a sapphire substrate, and the mask layer 12 of the Weiche is provided. When a current of 2 (? mA) is input to a hairpin having an emission center wavelength of 4 G5 nm, the output power is ～29.0 mW and the external quantum efficiency is increased. Like ~ 47.4%. Furthermore, in an equivalent semiconductor light-emitting device in which a u·(four) layer is provided without a photomask layer on a flat sapphire substrate, the output power is 2 〇.7 and the sub-efficiency is 33 hops, and SiO 2 is provided on a flat sapphire substrate. An equivalent semiconductor light-emitting device having a u_(10) layer provided thereon has an output of 23.5 mW and an external quantum efficiency of 38 4%.

The constituent material of the n^GaN layer is GaN doped with an n-type impurity (d〇pant). Examples of the n-type impurity 'e" include Si, Ge, and the like. The concentration of the n-type impurity is, for example, 1.0 Χ 10 Π 2 〇 x 〇 17 / cm 3 . &quot;secret layer Μ, == One layer composition, or it may be composed of a plurality of layers of different types and concentrations of η-type impurities. n type (10) 4 thickness 譬 ~ 10 / zm. The heavy well layer 15 has an alternating stack structure of the 15M° barrier layer 15b of the well layer. The number of layers of the well layer 15a and the barrier layer 15b is, for example, 5 to 15 layers. = The composition of the well layer can be exemplified by the city secret (four) logic. The thickness of the well layer 15a is, for example, 1 to 2 〇 nm. 8/22 201029233 As a constituent material of the barrier layer 15b, for example, InGaN (greater than the band gap of the well layer) can be cited. The thickness of the barrier layer i5b is 5 to 20 nm. The constituent material of the p-type AlGaN layer 16 is doped with p-type impurities.

AlGaN. The mixed crystal ratio of A1N is appropriately selected from 〇.〇5 to 0.3. As the p-type impurity, for example, Mg, Cd or the like can be mentioned. In the p-type, since the acceptor level is high, the impurity concentration and the free hole concentration differ greatly. Therefore, the free hole concentration measured by the cavitation with respect to the p-type is used as an evaluation index. The free hole concentration is, for example, ~5xl017/cm3. The thickness of the p-type AlGaN layer 16 is, for example, 10 to 30 nm. The constituent material of the p-type GaN layer 17 is doped with a p-type impurity. As a p-type impurity, as in the case of the p-type GaN, for example, ^^, (:: 1, etc., a hole effect is used. The measured free hole concentration is, for example, 2 〇χι〇ΐ7 to 10xl017/cm3. The P-type GaN layer 17 may be formed of a single layer, and may also be formed of a plurality of layers of different types and concentrations of P-type impurities. The thickness of the p-type GaN layer 17 is, for example, 50 to 2 〇〇 nm. Φ As the constituent electrode material of the 11-type electrode 18, for example,

A stacked structure of Ti/Al 'Ti/Al/Mo/Au, Hf/Au, or the like. The thickness of the n-type electrode 18 is, for example, Ti/Al (10 nm/500 nm). Examples of the p-type electrode 19 include a stacked structure such as pd/pt/Au, Ni/Au, Pd/Mo/Au, an alloy, or the like, or an oxide-based transparent conductive material such as IT〇 (indium tin oxide). . The thickness of the p-type electrode 19 is, for example, 10 to 200 nm. A pad electrode for wireb〇nding is required on the p-type electrode, and most of the cases are fabricated using the same material system as the n-type electrode. (Manufacturing method of semiconductor light-emitting device) 9/22 201029233 Next, a method of manufacturing the semiconductor light-emitting device 10 according to the present embodiment will be described with reference to Figs. 2(8) to (f). In the following method for manufacturing the semiconductor light-emitting device 10 according to the present embodiment, a photomask layer 12 of ruthenium oxynitride is provided on the sapphire wafer 1 (substrate 11), and u-GaN is sequentially formed thereon. Layer 13, n-type GaN layer 14 (doped with Si), multiple quantum well layers 15 of light-emitting layer (well layer 15a: InGaN, barrier layer i5b: GaN), p-type AlGaN layer 16 (doped with Mg), and p-type GaN After each of the semiconductor layers of the layer 17 (doped with Mg), an n-type electrode 18 and a p-type electrode 19 are formed on the n-type GaN layer 14 and the p-type GaN layer 17, respectively. &lt;Preparation of sapphire wafer&gt; Preparation of sapphire wafer 11 . The sapphire wafer 11, although it differs in diameter, has a thickness of 0.3 to 3.0 mm and a diameter of 50 to 300 mm. Further, in the case of a sapphire wafer 11' having a diameter of 50 mm, 5000 to 12,000 semiconductor light-emitting elements 10 can be produced on one sapphire wafer. &lt;Formation of Photomask Layer&gt; Examples of the method of forming the mask layer 12 include a plasma CVD method, a normal pressure CVD method, a sputtering method, and the like. The following describes the method of forming the photomask layer 12 using the plasma CVD method. In the plasma CVD apparatus used for forming the mask layer 12, a reaction gas supply unit constituting a high-frequency electrode is disposed above the stainless steel vacuum container, and a wafer stage of the opposite electrode is formed inside the vacuum container and is on the wafer stage. Install the heater. The interval between the reaction gas supply portion and the wafer stage is, for example, 2.0 to 3.0 cm. Further, the plasma CVD apparatus is constructed such that the layer 10 of the reticle 10/22 201029233 is deposited on the sapphire wafer 11' set on the wafer stage via the reaction gas. Using the above plasma CVD apparatus, the sapphire wafer 11 is set to face up after the wafer stage, and the temperature of the sapphire wafer ir is heated to 300 to 400 ° C and the discharge pressure in the reaction vessel is 2 〇. ~3〇〇Pa, as the reaction gas in the reaction cell, each is supplied with shredded pork,

SiH4), ammonia (NH3), nitrogen (N2), nitrous oxide (N20), and hydrogen (H2) are supplied at a flow rate of 1 to 1 〇mL/min (sccm), 0.5 to 1 OmL/min, and 1 ~

100 mL/min, 10 to 5000 mL/min, and 10 to 5 mL/min. Furthermore, the discharge frequency is from 1 kHz to 100 MHz, and the high frequency power is from 1 〇 to i 〇〇 w. At this time, as shown in Fig. 2 (8), a ruthenium oxynitride film is deposited on the surface of the sapphire wafer to form a mask layer 12. The refractive index of the formed photomask layer 12 can be controlled via the composition of the reaction gas supplied to the reaction vessel or the setting of the film formation conditions.譬 =, the refractive index is increased by increasing the ratio of the supply flow rate of the methane, and on the other hand, the refractive index can be lowered by increasing the ratio of the supply flow rate of the laughing gas or by increasing the high-frequency power. Therefore, in order to change the refractive index of the photomask layer 12 in the thickness direction, it is sufficient to change the composition of the reaction gas and the film formation conditions. Further, since the hydrogen contained in the reaction gas will cause the hydrogen atom in the photomask layer 12 to contain a hydrogen atom, a crack occurs in the photomask layer 12 due to the nitrogen atom from the heat treatment. k) or the bubble-like heat loss damage is significant, and brings the Z to the property y) of the mask layer 12; and, as described above, the mask can be reduced by using the same or a little gas as the methane. The hydrogen atom content of the layer 12 is. = ' As shown in Fig. 2(b), an opening I2a is formed in the photomask layer 12. The method of forming the opening 12a of the cap layer 12 may be, for example, a dry etching method such as reactivity 11/22 201029233 ion etching (Reactive Ion Etching: RIE) or a wet etching method using a hydrofluoric acid etching solution. &lt;Formation of Semiconductor Layer&gt; Examples of the method for forming each of the following semiconductor layers include Metal Organic Vapor Phase Epitaxy (MOVPE) and Molecular Epitaxy (M〇iecuiar Beam Epitaxy. MBE). ), Hydride Vapor Phase Epitaxy. 'HVPE, etc., among which organometallic vapor phase growth is the most common. Hereinafter, a method of forming each semiconductor layer using the organometallic vapor phase growth method will be described. The MOVPE devices used to form the respective semiconductor layers can be configured by an electronically controlled wafer transfer system, a wafer heating system, a gas supply system, and a gas exhaust system. Wafer heating system, thermocouple and resistance heating, carbon or SiC heating table provided thereon, and MOVPE device, set in the wafer heating system, on the heating table of the quartz disk (tray) The semiconductor layer is crystal grown on the sapphire wafer 11' according to the reaction gas. Formation of a -u-GaN layer - Using the MOVPE device described above, the mask layer 12 of the sapphire wafer 1 provided with the mask layer 12 is placed on the quartz disk with the surface facing up, and the sapphire wafer is heated to 1 1050 to 115 (TC and the pressure in the reaction vessel is 10k to 100 kPa, and H2 is supplied as a carrier gas in the flow path provided in the reaction container, and the state is kept for several minutes to heat the sapphire wafer u· (thermal cleaning) Next, the temperature of the sapphire wafer 11 is 1050 to 1150 〇c, and the pressure in the container is 10k~l〇〇kpa, and the carrier gas H2 is taken into the reaction vessel. The flow rate around L/min is circulated, and as the reaction gas 12/22 201029233, the V element supply source _3) and the steroid element supply source (TMG) are supplied so that their respective flows are G.ML/- , and 5G ~. S &quot; At this time, although the crystal growth does not occur from the surface of the photomask layer 12, the surface of the sapphire wafer 11 exposed from the opening 12a formed in the photomask layer 12 is the starting point 'on which is undoped The GaN crystal grows, and as shown in Fig. 2 (6), a u-GaN layer 13 is formed on the mask layer 12. Further, in a portion of the opening 12a where the mask layer 12 is formed, GaN is grown in a sapphire wafer in the normal direction of the surface, and on the other hand, a portion of the mask® I 12 outside the opening 12a is formed. The layer covering the portion is formed by crystal growth and crystallization in the lateral direction via GaN. Further, when the low temperature buffer layer is formed before the formation of the u_GaN layer 13, the temperature of the sapphire wafer 11' is made 4 〇〇 to 5 〇〇〇 c to crystallize the GaN. - Formation of n-type GaN layer - The pressure in the reaction vessel is l〇k~i〇〇kpa, and is 5 to 15 L/min in the reaction vessel (hereinafter, the gas flow rate is used as a reference state (0 〇 c, 1 gas pressure) The flow rate of the value of Φ causes the carrier gas H2 to flow, and supplies the group V element supply source (NH3), the group III element supply source i (TMG), and the n-type doping element supply source (SiH4) as a reaction gas. The flow rates were respectively oi~5L/min, 5〇~150#mol/min, *l~5xl〇-3; czmol/min. At this time, as shown in FIG. 2(d), the u-GaN layer 13 then crystallizes the n-type GaN to form the n-type GaN layer 14. _The formation of multiple quantum well layers -

The temperature of the sapphire wafer ir is about 8 〇 o ° c and the pressure in the reaction vessel is l〇k to 100 kPa, and the carrier gas N2 is caused to flow in the reaction vessel at a flow rate of 5 to 15 L/min. As a reaction gas, V 13/22 201029233 group element supply source (NH3), group III element supply source KTMG), and m group element supply source 2 (TMI) are supplied, and the flow rates thereof are each 〇" to 5 L/min, 5~15 &quot;mol/min, and 2~30&quot;mol/min. At this time, the n-type GaN layer 14 is followed to crystallize the InGaN crystal to form the well layer i5a. Next, the supply flow rates of the group v element supply source (NH3) and the lanthanum element supply source (TMG) are each made equal to $~丨 mol/min. At this time, the well layer 15a of InGaN is grown to form (10) crystals to form the barrier layer 15b. Further, the same operation as described above is alternately repeated, and as shown in Fig. 2(e), the multiple quantum well layers 15 are formed by alternately forming the well layer 15a and the barrier layer 15b. Furthermore, the emission wavelength of the multiple quantum well layer 15 depends on the well width (thickness of the well layer) and the InN mixed crystal ratio of the well layer 15a, and the higher the InN mixed crystal ratio, the longer the wavelength becomes. The InN mixed crystal ratio is determined according to the MMI flow rate of TMI / (mole flow of TMG + molar flow of TMI). -P-type AlGaN layer and GaN layer formation - the temperature of the sapphire wafer 1 为 1000 〇〇 〇〇 并使 并使 并使 并使 并使 并使 并使 并使 并使 并使 并使 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应 反应The flow rate causes the carrier gas H2 to flow, and supplies a group V element supply source (NH3), a group III element supply source 1 (TMG), a steroid element supply source 3 (TMA), and a p-type doping element supply source as a reaction gas. (Cp2Mg), so that their respective supply flow is 0.1 to 5 L/min, 50 to 150 //mol/min, 2 to 80 //mol/min, and 〇.〇3 to 30//mol/min. At the same time, as shown in FIG. 2(f), the multi-quantum well layer 15 is followed to crystallize the AlGaN crystal to form the p-type AlGaN layer 16. Next, as a reaction gas, a group V element supply source (NH3), a group III element supply source 1 (TMG), and a p type doping element supply source (Cp2Mg) are supplied, 14/22 201029233, and their respective supply flows are set to 〇1~5L/min, %~i5〇&quot;mol/min, and 0.03~30^m〇i/min. At this time, as shown in FIG. 2(f), the p-type GaN layer 16 is subsequently grown to form a p-type GaN layer π. &lt;Formation of Electrodes&gt; After the n-type (10) layer 14 is exposed by partially displacing the ionic surface of the sapphire wafer of the semiconductor layer formed by stacking, according to a method such as vacuum vapor deposition CVD (Chemical Vapor Deposition) An n-type electrode 18 is formed on the n-type (10) layer 14 and a p-type electrode 19 is formed on the p-type GaN layer 17. One is divided into individual semiconductor light-emitting elements 10 by cutting the sapphire wafer u. [Examples] (Test evaluation 1) Except that a plurality of grooves extending in parallel (corresponding to the opening of the mask layer of the above-described embodiment) were formed on the sapphire; 5 substrate, and then the layer (~) was provided. The external quantum efficiency of the semiconductor light-emitting device having the same structure as that of the above embodiment was 43%. Further, in the above-described semiconductor light-emitting device, the semiconductor light-emitting device of the above-described embodiment has a case where the refractive index of the photomask layer is the same as the refractive index of the sapphire substrate. The external quantum efficiency of the semiconductor light-emitting device having the same configuration as that of the above embodiment except that the u GaN layer was provided on the flat sapphire substrate without the mask layer was provided, the external quantum efficiency was 33 8%. Further, in the semiconductor light-emitting device of the above-described embodiment, the refractive index of the phase mask layer and the refractive index of the u-GaN layer are in the case of the semiconductor light-emitting device. w 'In addition to the parallel embossed plural 15/22 201029233 formed on a flat sapphire substrate, a layer of this light-emitting component with the same quantum efficiency is the same structure, and the external ratio is simulated. The refractive index of the leather layer, the external amount:!: ί, when the refractive index of the mask layer is "6 (four), the nominal rate is 43.2', when the refractive index of the mask layer is 1.88, the efficiency is 42.8, when the mask When the refractive index of the layer is 2 〇1

The amount of money is 42. When the refractive index of the mask layer is 221, the external amount; the efficiency is 41.0 'when the refractive index of the layer is 2.35, the external quantum efficiency is 37.8 ', and when the refractive index of the mask layer The rate was 23.8 and the rate was 33.8. Ha Figure 3 shows the relationship between the refractive index and the external efficiency of the mask layer based on the above results. According to Fig. 3, it can be seen that the external quantum efficiency is increased by making the refractive index of the photomask layer larger than the refractive index of SiO 2 and smaller than the refractive index of the GaN layer. (Test Evaluation 2)

Using a plasma CVD apparatus (interval between the reaction gas supply unit and the wafer stage: 25 mm) 'After setting the sapphire wafer on the wafer stage, the temperature of the sapphire wafer is heated to 350X: and the discharge in the reaction vessel is made. Methane, ammonia, and nitrogen were supplied as reaction gases to the reaction vessel at a pressure of 100 Pa', and the flow rates were 5 mL/min, 2 mL/min, and 50 mL/min, respectively, to deposit a film on the sapphire wafer. Further, the discharge frequency was 13.56 MHz, and the high frequency power was 50 W. For the film formed by deposition, a spectrum of infrared absorption 16/22 201029233 was analyzed using a Fourier transform infrared spectrophotometer (manufactured by Nanometrics Inc., model: QS1200), and it was found to be a nitride. Further, regarding this nitriding film, the refractive index measured by an EllipSometer (manufactured by Horiba, Ltd., trade name: UVISEL/M200-VIS-AG-200S) is 2, followed by supply as a reaction gas. Laughing this point is not the same as the above-mentioned _ ground deposition type lysate film 1 (four) gas supply flow plural number: owe to the lion. And 'there is a nitroxene _ measuring its refractive index. Fig. 4 shows the relationship between the supply flow rate of the laughing gas and the refractive index of the nitrous oxide film φ formed by the deposition. According to Fig. 4, it is found that if the supply flow rate of laughing gas increases in the range of 0 to 6 mL/min, the refractive index of the nitrous oxide film will decrease from 2 到 to about i6. Further, it can be seen that when the supply flow rate of the laughing gas is about 3 mL/min, the refractive index of the yttrium oxynitride film is 17 as in the case of sapphire. (Test Evaluation 3) Using the same plasma CVD apparatus as Test Evaluation 2, after the sapphire wafer was set on the wafer stage, the temperature of the sapphire wafer was heated to 35 〇 ° ° C and the discharge pressure in the reaction vessel was made. As a reaction gas, as a reaction gas, the reaction vessel was supplied with Shixia, Nitrogen and Naughty gas at respective flow rates of 5 mL/min, 2 mL/min, 50 mL/min, and 3 mL/min on the sapphire wafer. A film of arsenic oxynitride is formed on the upper layer. Further, the discharge frequency was 13.56 MHz, and the high frequency power was 50 W. Next, in the same manner as described above, the film was recorded in the same manner as described above except that the reaction gas was supplied with hydrogen. A film is deposited by the supply flow of a plurality of money thieves. Further, the inner 17/22 201029233 stress was measured using a flatness tester (manufactured by NIDEK Co., Ltd., model: FT_9〇〇) for each of the film-formed nitrous oxide films. Fig. 5 shows the relationship between the supply flow rate of hydrogen and the internal stress of the antimony telluride film. According to FIG. 5, it can be seen that as the argon supply flow rate increases, the internal stress changes in the direction in which the compressive stress increases, and the internal pressure of the hydrogen supply flow rate is approximately 20 mL/min, and the internal stress is rapidly changed from the tensile side to the compression side. . Therefore, it can be considered that the internal stress of the tantalum oxide thin film can be controlled by manipulating the supply flow rate of hydrogen. Furthermore, there is a problem with the internal stress of the film: if the large tensile stress acts to heat the film, the thermal expansion of the film is liable to cause cracking. On the other hand, there is a problem that if a large compressive stress acts, heat treatment When hydrogen or the like is removed, unevenness in surface morphology is likely to occur. (Test Evaluation 4) In addition to the argon which replaced a part or the whole of the nitrogen as an inert gas as a reaction gas, the reaction gas was the same as the methane, ammonia and nitrogen in the test evaluation 2 on the sapphire wafer. The deposition forms a thin film of cerium oxynitride. The film formation is deposited by changing the amount of substitution of argon several times. Further, the internal stress of each of the formed nitrous oxide films was measured. When it is known that the amount of substitution of argon increases, the internal stress changes in the direction in which the compression is large, and when all of the nitrogen is replaced by argon, it is a compressive stress of about 108 Pa. Therefore, it can be considered that the internal stress of the film of yttrium oxynitride can be controlled by the amount of substitution of the inert gas which manipulates a part of the replacement nitrogen. (Test Evaluation 5) In addition to changing the discharge frequency, the yttrium oxynitride film was formed on the sapphire wafer 18/22 201029233 in the same manner as in the test evaluation 2, the reaction gas was 矽methane, ammonia, and nitrogen. . A thin film is deposited by changing the discharge frequency a plurality of times.

Further, the internal stress of each of the formed yttria thin films was measured. As a result, when the discharge frequency is low, the internal stress is rapidly lowered from the tensile side to the compression side in the vicinity of the ion plasma frequency, and becomes a compressive stress of ixl 〇 8 Pa or less at 4 MHz. Therefore, it can be considered that the internal stress of the yttrium oxynitride film can be controlled by operating the discharge frequency. [Possibility of industrial use]

[图 =:] Semi-conductive light-emitting elements and their manufacturing methods are extremely useful

1 is a cross-sectional view showing a semiconductor light emitting device of an embodiment. Fig. 3 is a diagram showing the manufacturing method of the refractive index and the external quantum efficiency of the photomask layer. Fig. 4 (4) Supply flow rate Wei oxygen is the supply flow rate of hydrogen and the nitrogen oxide sand Diagram relationship [Main component symbol description] 10 Semiconductor light-emitting element 11 Substrate 12 Photomask layer 12a Opening 13 u-GaN layer 14 n-type GaN layer 15 Multiple quantum well layer 15a Well layer 19/22 201029233 15b barrier layer 16 p type AlGaN layer 17 p-type GaN layer 18 n-type electrode 19 p-type electrode

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Claims (1)

201029233 VII. Patent application scope · L semiconductor light-emitting device, the semiconductor light-emitting device includes: a substrate, a surface on which crystals having GaN can grow, and a if of the cup is formed to cover the surface of the substrate Opening the surface of the surface of the surface 2 and having crystals of GaN that cannot grow ❹ exposing the photomask layer and the opening GaN=? refractive index of the opening from the opening is greater than _ and less than the above 2 The semiconductor light-emitting device according to Item 1, wherein the photomask layer has a refractive index greater than Μ1 2 and less than 2 Μ. , the piece, = the semi-luminous illuminating element described in the application. The first cover layer is formed by yttrium oxynitride. The semiconductor = read as described in any one of items 1 to 3, wherein the refractive index of the photomask layer is changed by 21/22 1 in the thickness direction. For example, t material _ 4 unmarked half-element light-emitting element, in the basin The refractive index of the mask layer changes gradually from the (10) layer side in the thickness direction toward the substrate side. 2. If you apply for a patent scope! To one of the light-emitting elements, wherein the substrate is a blue f-stone substrate. A method of manufacturing a semiconductor light-emitting device, wherein: the semiconductor light-emitting device comprises: a substrate, a surface capable of growing crystals having GaN, and a light single layer of 201029233, which is formed to cover a surface of the substrate a surface in which a surface portion of the substrate is exposed and having a surface in which crystallization of GaN cannot grow, and a surface of the GaN layer covered with the photomask layer and exposed from the opening of the photomask layer; deposited by CVD The photomask layer is formed such that the refractive index of the photomask layer is greater than the refractive index of Si〇2 and smaller than the refractive index of the GaN layer.