Classifications

• • C—CHEMISTRY; METALLURGY
  • C30—CRYSTAL GROWTH
  • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
  • C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
• • C—CHEMISTRY; METALLURGY
  • C30—CRYSTAL GROWTH
  • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
  • C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
  • C30B25/02—Epitaxial-layer growth
• • C—CHEMISTRY; METALLURGY
  • C30—CRYSTAL GROWTH
  • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
  • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
  • C30B29/10—Inorganic compounds or compositions
  • C30B29/40—AIIIBV compounds wherein A is B, Al, Ga, In or Tl and B is N, P, As, Sb or Bi
  • C30B29/403—AIII-nitrides
• • C—CHEMISTRY; METALLURGY
  • C30—CRYSTAL GROWTH
  • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
  • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
  • C30B29/10—Inorganic compounds or compositions
  • C30B29/40—AIIIBV compounds wherein A is B, Al, Ga, In or Tl and B is N, P, As, Sb or Bi
  • C30B29/403—AIII-nitrides
  • C30B29/406—Gallium nitride

Definitions

• the invention relates to a process for the growth of nitrogen-containing semiconductor crystal materials of the form A X B Y C Z N V M W , where A, B, C is a group II or III element, N nitrogen, M is a group V or VI element and X, Y, Z, W represent the mole fraction of each element of this compound, using an intermediate layer for the growth support z.
• the method used to date is based on a two-step initial growth process, which is composed of a low-temperature growth step, also known as buffer layer growth, and the subsequent high-temperature growth [JP / B2 / 93].
• the change in the growth regime ie the transition from the cubic to the hexagonal crystal structure for the growth interruption between the two temperature regimes, is a prominent factor, since it is assumed that the low-temperature buffer layer is recrystallizing [BOY98], [MTF + 98], [WKT + 96].
• This two-step initial growth process is susceptible to reproducibility of the nucleation layers due to the various changes in growth parameters and susceptible to non-uniformities across the wafer. This has a considerable influence on the properties of the components made from it.
• the luminosity and color of an LED is difficult to control using the two-step process.
• the electrical direct current and high frequency properties of FET vary very widely.
• the complicated manufacturing process which is based on the well-known two-step layer growth, which consists of a buffer layer and the deep substrate temperature temperature and further growth at a higher temperature on this buffer layer is avoided.
• the advantages of the new process are better reproducibility and lower manufacturing costs for components.
• the new initial growth procedure therefore prevents the two-step layer growth and thus avoids the manufacturing process with many necessary process steps. As a result, the manufacturing time and cost of a nitrogen-containing semiconductor crystal layer are reduced. At the same time, improved structural, electrical and optical properties are achieved.
• the critical layer thickness of the nitrogen-containing semiconductor material on sapphire, SiC or Si has reached the critical layer thickness before the recrystallization takes place during the heating process.
• the object of the invention is to produce a first layer on a substrate. This layer has further influence on the subsequent layers. This means that in addition to determining the composition, doping and layer sequence, an optimal coordination of the subsequent layers should be made possible while taking into account further desired properties described below. Complicated manufacturing processes with many process steps should be avoided. As a result, manufacturing time and costs are reduced.
• the object on which the invention is based is achieved by a method according to claim 1. Further developments of the method according to the invention are the subject of claims 2 to 8.
• the object on which the invention is based is achieved by a continuous growth process.
• a x B ⁇ C z , N v , M w materials and layer systems and doped layer systems can advantageously be produced.
• a high degree of homogeneity can advantageously also be achieved in a lateral direction.
• Components can advantageously be produced.
• Quantum pots can advantageously be produced.
• n- and p-doping can be carried out simultaneously.
• a reproducible production of A X B Y C Z ( N V , M W materials with different compositions X, Y, Z, V, W and different purities can advantageously be made possible.
• Another advantageously predeterminable property is the surface morphology of the semiconductor materials.
• Properties which can be advantageously predefined are the particle density and the impurity density on the wafer surface.
• Another advantage is to enable a reproducible and very uniform or uniform application of A x _ B ⁇ C z , N v , M w components with respect to doping, layer thickness, composition and all other properties that are important for expenditure.
• a process is described for the initial growth of nitrogen-containing semiconductor crystal materials of the form A X B Y C Z N V M W (A, B, C represent a group II or III element, N nitrogen, M a group V or VI- Element and X, Y, Z, W is the mole fraction of each element in this compound) on sapphire, SiC and Si using different ramp functions that allow a continuous change in growth parameters during initial growth.
• This new initial growth process is characterized in that during the initial growth process of the nitrogen-containing semiconductor crystal materials on sapphire, SiC or Si, no abrupt change in the growth regime is required in order to realize a suitable structure for the further high-temperature growth.
• the Al 2 0 3 substrate was exposed to a hydrogen atmosphere (150 mbar) for 30 min 1200 ° C heated [KWH + 98]. After this desorption step, the substrate temperature was then lowered to 530 ° C to ensure a reproducible initial situation for further growth. At this temperature, NH 3 was then fed into the reactor with a flow of 4500 sccm. Based on this substrate temperature, a linear ramp function was then used (from 830 ° C to 1200 ° C in 8min) to reach the usual high growth temperature of 1200 ° C. At the moment of starting the heating, TMGa was fed into the reactor with a low flow of 20sccm, which leads to GaN growth with a low growth rate.
• a low growth rate layer was then grown for 4 minutes.
• a ramp function linear ramp of the TMGa flow from 20sccm to 80 sccm in 15min
• a 2 ⁇ m thick GaN layer and a 5-fold MQW GalnN / GaN were then deposited on this adaptation layer.
• the following layer structure serves as a test structure: 5x 2nm InGaN / 15nm GaN 2 ⁇ m GaN: Si buffer layer 20nm GaN nucleation layer 400 ⁇ m sapphire substrates (0001)
• the first nucleation layer is deposited at 530 ° C. under an N 2 atmosphere at 950 mbar for 8 minutes.
• the layer has cubic components and is not connected.
• growth is interrupted and heating to 1170 ° C.
• a recrystallization takes place from the cubic crystal phase into the hexagonal phase.
• the GaN buffer layer then grows at 1160 ° C.
• continuous growth takes place when heating from 530 ° C. to 1170 ° C. without any interruption in growth and without any healing step which would allow recrystallization.
• the growth takes place under H 2 at 200 mbar.
• the comparison of the properties in Table 1 shows a higher luminous efficiency with the emission wavelength remaining the same.
• Literature The comparison of the properties in Table 1 shows a higher luminous efficiency with the emission wavelength remaining the same.

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Crystallography & Structural Chemistry (AREA)
• Materials Engineering (AREA)
• Metallurgy (AREA)
• Inorganic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Led Devices (AREA)
• Crystals, And After-Treatments Of Crystals (AREA)
• Chemical Vapour Deposition (AREA)
• Recrystallisation Techniques (AREA)

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• 2000
  • 2000-07-24 US US09/624,252 patent/US7473316B1/en not_active Expired - Fee Related
• 2001
  • 2001-04-12 TW TW090108754A patent/TW507272B/zh not_active IP Right Cessation
  • 2001-04-12 WO PCT/DE2001/001446 patent/WO2001077421A1/de not_active Application Discontinuation
  • 2001-04-12 JP JP2001575266A patent/JP2003530707A/ja active Pending
  • 2001-04-12 KR KR1020027013691A patent/KR20030001416A/ko not_active Application Discontinuation
  • 2001-04-12 EP EP01933606A patent/EP1272693A1/de not_active Withdrawn

Non-Patent Citations (1)

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