Multiquantum barrier structure and semiconductor laser diode

• US 5,544,187 A
• Filed: 11/17/1994
• Issued: 08/06/1996
• Est. Priority Date: 11/25/1993
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Kato, Manabu, Motoda, Takashi, Kadoiwa, Kaoru
• Primary Examiner(s): Bovernick, Rodney B.
• Assistant Examiner(s): Song, Yisun
• Application Number:
  US08/343,909
• Time in Patent Office: 628 Days
• Field of Search: 372/46, 372/45
• US Class Current: 372/45.012
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 5/20 Structure or shape of the semiconductor body to guide the optical wave ; Confining structures perpendicular to the optical axis, e.g. index or gain guiding, stripe geometry, broad area lasers, gain tailoring, transverse or lateral reflectors, special cladding structures, MQW barrier reflection layers
• CPC Class Codes: H01S 5/2013 MQW barrier reflection layers
• CPC Class Codes: H01S 5/34326 with a well layer based on InGa(Al)P, e.g. red laser
• CPC Class Codes: Y10S 977/761 Superlattice with well or barrier thickness adapted for increasing the reflection, transmission, or filtering of carriers having energies above the bulk-form conduction or valence band energy level of the well or barrier, i.e. well or barrier with n-integer-λ-carrier-/4 thickness
• CPC Class Codes: Y10S 977/833 Thermal property of nanomaterial, e.g. thermally conducting/insulating or exhibiting peltier or seebeck effect

Abstract

A multiquantum barrier (MQB) structure includes a first superlattice layer and a second superlattice layer disposed continuously with the first superlattice layer. The first superlattice layer includes well layers having the same thickness and barrier layers having the same thickness, the well layers and barrier layers being alternatingly laminated. The second superlattice layer includes well layers having the same thickness, the well and barrier layers being alternatingly laminated. The second superlattice layer has a high electron reflectivity in an electron energy region where the electron reflectivity of the second first superlattice structure is low. Therefore, the high reflectivity of the second superlattice layer compensates for the low reflectivity of the first superlattice layer whereby a high electron reflectivity is maintained in the MQB structure.

Claims

1. A multiquantum barrier structure including a superlattice structure in which a plurality of well layers and a plurality of barrier layers are alternatingly laminated, said superlattice structure comprising:

a first superlattice layer comprising at least four Ga₀.5 In₀.5 well layers each well layer being four monolayers thick, and at least four (Al₀.7 Ga₀.3)₀.5 In₀.5 P barrier layers, each barrier layer being two monolayers thick, said well layers and barrier layers being alternatingly arranged, said first superlattice layer having a first electron reflectivity in an electron energy region; and

a second superlattice layer disposed continuously with the first superlattice layer and comprising at least four Ga₀.5 In₀.5 P well layers, each well layer being four monolayers thick, and at least four (Al₀.7 Ga₀.3)₀.5 In₀.5 P barrier layers, each barrier layer being four monolayers thick, said well layers and barrier layers being alternatingly arranged, said second superlattice layer having a second electron reflectivity, higher than the first electron reflectivity, in the electron energy region where the first superlattice structure has the first electron reflectivity.

2. A multiquantum barrier structure including a superlattice structure in which a plurality of well layers and a plurality of barrier layers are alternatingly laminated, said superlattice structure comprising:

a first superlattice layer comprising at least four Ga₀.5 In₀.5 P well layers, each well layer being four monolayers thick, and at least four (Al₀.7 Ga₀.3)₀.5 In₀.5 P barrier layers, each barrier layer being three monolayers thick, said well layers and barrier layers being alternatingly arranged, said first superlattice layer having a first electron reflectivity in an electron energy region; and

a second superlattice layer disposed continuously with the first superlattice layer and comprising at least four Ga₀.5 In₀.5 P well layers, each well layer being four monolayers thick, and at least four (Al₀.7 Ga₀.3)₀.5 In₀.5 P barrier layers, each barrier layer being five monolayers thick, said well layers and barrier layers being alternatingly arranged, said second superlattice layer having a second electron reflectivity, higher than the first electron reflectivity, in the electron energy region where the first superlattice structure has the first electron reflectivity.

3. A multiquantum barrier structure including a superlattice structure in which a plurality of well layers and a plurality of barrier layers are alternatingly laminated, said superlattice structure comprising:

a first superlattice layer comprising at least four Ga₀.5 In₀.5 P well layers, each well layer being four monolayers thick, and at least four (Al₀.7 Ga₀.3)₀.5 In₀.5 P barrier layers, each barrier layer being two monolayers thick, said well layers and barrier layers being alternatingly arranged, said first superlattice layer having a first electron reflectivity in an electron energy region;

a second superlattice layer disposed continuously with the first superlattice layer and comprising at least four Ga₀.5 In₀.5 P well layers, each well layer being four monolayers thick, and at least four (Al₀.7 Ga₀.3)₀.5 In₀.5 P barrier layers, each barrier layer being four monolayers thick, said well layers and barrier layers being alternatingly arranged, said second superlattice layer having a second electron reflectivity, higher than the first electron reflectivity, in the electron energy region where the first superlattice structure has the first electron reflectivity; and

a third superlattice layer disposed continuously with the second superlattice layer and comprising at least four Ga₀.5 In₀.5 P well layers, each well layer being four monolayers thick, and at least four (Al₀.7 Ga₀.3)₀.5 In₀.5 P barrier layers, each barrier layer being six monolayers thick, said well layers and barrier layers being alternatingly arranged, said third superlattice layer having a third electron reflectivity, higher than the first electron reflectivity, in the electron energy region where the first superlattice structure has the first electron reflectivity.

4. A multiquantum barrier structure including a superlattice structure in which a plurality of well layers and a plurality of barrier layers are alternatingly laminated, said superlattice structure comprising:

a first superlattice layer comprising at least four Ga₀.5 In₀.5 P well layers, each well layer being four monolayers thick, and at least four (Al₀.7 Ga₀.3)₀.5 In₀.5 P barrier layers, each barrier layer being three monolayers thick, said well layers and barrier layers being alternatingly arranged, said first superlattice layer having a first electron reflectivity in an electron energy region;

a second superlattice layer disposed continuously with the first superlattice layer and comprising at least four Ga₀.5 In₀.5 P well layers, each well layer being four monolayers thick, and at least four (Al₀.7 Ga₀.3)₀.5 In₀.5 P barrier layers, each barrier layer being four monolayers thick, said well layers and barrier layers being alternatingly arranged, said second superlattice layer having a second electron reflectivity, higher than the first electron reflectivity, in the electron energy region where the first superlattice structure has the first electron reflectivity; and

a third superlattice layer disposed continuously with the second superlattice layer and comprising at least four Ga₀.5 In₀.5 P well layers, each well layer being four monolayers thick, and at least four (Al₀.7 Ga₀.3)₀.5 In₀.5 P barrier layers, each barrier layer being five monolayers thick, said well layers and barrier layers being alternatingly arranged, said third superlattice layer having a third electron reflectivity, higher than the first electron reflectivity, in the electron energy region where the first superlattice structure has the first electron reflectivity.