Electrically tunable fabry-perot structure utilizing a deformable multi-layer mirror and method of making the same

• US 6,324,192 B1
• Filed: 04/14/1998
• Issued: 11/27/2001
• Est. Priority Date: 09/29/1995
• Status: Expired due to Fees

• Current Assignee: Hanger Solutions, LLC (IP Investments Group LLC)
• Original Assignee: Coretek, Inc. (Nortel Networks Corporation)
• Inventors: Tayebati, Parviz
• Primary Examiner(s): Arroyo, Teresa M.
• Assistant Examiner(s): MENEFEE, JAMES A
• Application Number:
  US09/059,877
• Time in Patent Office: 1,323 Days
• Field of Search: 372/43-46, 372/50, 372/96, 372/99, 372/20
• US Class Current: 372/20
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26
• CPC Class Codes: G02B 26/002 the movement or the deformation controlling the frequency of light, e.g. by Doppler effect
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: H01S 5/0614 controlled by electric field, i.e. whereby an additional electric field is used to tune the bandgap, e.g. using the Stark-effect
• CPC Class Codes: H01S 5/18363 comprising air layers
• CPC Class Codes: H01S 5/18366 Membrane DBR, i.e. a movable DBR on top of the VCSEL
• CPC Class Codes: H01S 5/18372 by native oxidation

Abstract

An electrically tunable Fabry-Perot structure using a deformable multi-layer mirror construction wherein Ga_1−aAl_aAs, where a <0.1, is used as the sacrificial layer which may be selectively removed using a citric acid enchant. The multi-layer mirrors consist of N and M period of quarter wavelength layers where N and M are integers, or integers plus 1/2. Further, the mirrors are made from alternating layers of Ga_1−xAl_xAs, where X>0.96, and a material selected from the group consisting of either Ga_1−zAl_zAs, where 0.7>Z>0, or Ga_1−yAl_yAs/Ga_1−zAl_zAs/Ga_1−yAl_yAs, where 0.7>Z>0 and y>0.5. The Ga_1−xAl_xAs is wet oxidized by exposing its edge to water in a nitrogen or helium atmosphere at a temperature of between about 360° C. and 450° C. so as to transform it to AlO_x. The resulting AlO_x layers abut the sacrificial layer and act as etch stops during the formation of a cantilever Fabry-Perot structure by etching of the sacrificial layer.

Claims

1. An electrically tunable vertical cavity surface emitting laser comprising:

a laterally-extending base comprising an optically-transparent semi-conductor material;

a first laterally-extending mirror comprising alternating layers of (i) said optically-transparent semiconductor material, and (ii) air;

a second laterally-extending mirror comprising alternating layers of (i) said optically-transparent semiconductor material, and (ii) air;

a laterally-extending layer of multiple quantum well material defining a laterally-extending P-I-N junction therein;

said first laterally extending mirror being fixedly mounted to said laterally extending base;

said laterally-extending layer of multiple quantum well material being fixedly mounted to said first laterally extending mirror;

said second laterally extending mirror being movably mounted to said laterally-extending layer of multiple quantum well material such that an air gap extends between said second laterally-extending mirror and said layer of multiple quantum well material;

a first electrode electrically connected to said second laterally-extending mirror; and

a second electrode electrically connected to said base;

whereby when a voltage difference is applied across said first and second electrodes, the electrically tunable, vertical cavity, surface emitting laser will change its lasing wavelength in response to the electrostatically induced movement of said first and second laterally-extending mirrors relative to one another.

2. An electrically tunable vertical cavity surface emitting laser according to claim 1 wherein said second laterally-extending mirror is mounted to said laterally-extending multiple quantum well material with a cantilever construction.

3. An electrically tunable vertical cavity surface emitting laser according to claim 1 wherein said second laterally-extending mirror is mounted to said laterally-extending multiple quantum well material with a trampoline construction.

4. An electrically tunable vertical cavity surface emitting laser comprising:

a laterally-extending base comprising an optically-transparent semiconductor material;

a first laterally-extending mirror comprising alternating layers of (i) said optically-transparent semiconductor material, and (ii) AlO_x;

a second laterally-extending mirror comprising alternating layers of (i) said optically-transparent semiconductor material, and (ii) AlO_x;

a laterally-extending layer of GaAlAs or GaInAs based multiple quantum well material defining a laterally-extending P-I-N junction therein;

said first laterally-extending mirror being fixedly mounted to said laterally-extending base;

said laterally-extending layer of GaAlAs or GaInAs based multiple quantum well material being fixedly mounted to said first laterally-extending mirror;

said second laterally-extending mirror being movably mounted to said laterally-extending layer such that an air gap extends between said laterally-extending layer and said second laterally-extending mirror;

a first electrode electrically connected to said second laterally-extending mirror; and

a second electrode electrically connected to said base;

whereby when a voltage difference is applied across said first and second electrodes, the electrically tunable vertical cavity surface omitting laser will change its lasing wavelength in response to the electrostatically induced movement of said first and second laterally-extending mirrors relative to one another.

5. An electrically tunable vertical cavity surface emitting laser according to claim 4 wherein said second laterally-extending mirror is mounted to said laterally-extending layer of GaAlAs or GaInAs based multiple quantum well material with a cantilever construction.

6. An electrically tunable vertical cavity surface emitting laser according to claim 4 wherein said second laterally-extending mirror is mounted to said laterally-extending layer of GaAlAs or GaInAs based multiple quantum well material with a trampoline construction.

7. An electrically tunable vertical cavity surface emitting laser according to claim 4 wherein said base comprises GaAs, and said first and second mirrors comprise alternating layers of (i) a material selected from the group consisting GaAs;

GaAlAs; and

Ga<sub>1−

y</sub>Al_yAs/Ga<sub>1−

z</sub>Al_zAs/Ga<sub>1−

y</sub>Al_yAs where y>

0.5 and where Z<

0.7, and (ii) AlO_x.