Abstract: A method for producing a vertical-cavity surface-emitting laser, includes the steps of: forming a bottom mirror layer, an active layer and a top mirror layer on a semiconductor substrate; forming an antireflection layer on a rear surface of the semiconductor substrate; selectively etching peripheral portions of the antireflection layer to form a first electrode; defining laser emission portions through etching processing; forming a hydrogenated barrier over an entire surface of the resultant structure; forming a post; forming a passivation layer through the hydrogenating of the exposed top mirror layer and the portions of the active layer; forming a planarization film after the partial exposure of the top mirror and forming a second electrode pad to which the exposed top mirror layer contacts.

Abstract: An improved parallel optical logic operator provides a path for light to pass through substrates in which a light source and an optical logic device are arranged. An optical logic device operates by transmission of light forwarded to a predetermined direction. This increases integration efficiency of the system by eliminating optical parts for changing the light path. A unit chip includes a laser array for generating a predetermined light in accordance with an electrical signal for a logic process, a laser array substrate on which via holes are formed for passing light, a microlens array for converting the light beam emitted from each laser device of the laser array into a parallel light beam for passing through the via hole, and an optical logic circuit array formed with a combination of an S-SEED which performs a logic function by transmission of the light signal through an optical window in S-SEED.

Abstract: An optical controlled resonant tunneling oscillator utilizing variation of a resonant tunneling oscillator in accordance with a negative differential resistance, a series resistance and a static capacitance varied in response to the intensity of light when light is incident on a resonant tunneling device having a double barrier quantum well structure and a method for fabricating the same are disclosed. The oscillator modulates the frequency over 2 or 3 levels in response to the intensity of incident light as compared to a conventional photoelectric system that modulates the frequency in response to the ON/OFF electric signal, thereby simplifying the system. The oscillator controls the resonant tunneling at high speed level with light enably processing a signal from tens to hundreds of GHz.

Abstract: A method for non-active processing of an etched surface in a vertical-cavity surface-emitting laser diode is provided. In order to obtain a stable single fundamental transverse mode, at a low temperature of 100 to 300 degrees, an amorphous GaAs is deposited on a surface of an etched active layer and an etched cavity. Also, a bottom emitting laser is provided which is formed by, with the metal electrode as a mask, etching the top mirror layer and the active layer, depositing the amorphous GaAs onto the etched portion and planarizing the deposited GaAs layer and depositing p-type metal pad over the amorphous GaAs around the formed laser device. Also, a top emission type laser is provided which is formed by, with a photoresist as a mask, etching the top mirror layer and the active layer, planarizing the GaAs layer and depositing p-type metal pad containing a window for light emission which is made smaller than laser area over the amorphous GaAs around the formed laser device.

Abstract: An optical controlled resonant tunneling oscillator utilizing an oscillation variation characteristic of a resonant tunneling oscillator in accordance with a negative differential resistance, a series resistance and a static capacitance varied with an intensity of light when the light is incident on a resonant tunneling device having a double barrier quantum well structure and a method for fabricating the same are disclosed. The oscillator can modulate the frequency 2 or 3 levels in response to an intensity of an incident light as compared with the method of a conventioal photoelectric system that modulates the frequency in response to ON/OFF of an electric signal, thereby simplifying the system. The oscillator controls the resonant tunneling at the high speed by light, thereby enabling processing a signal of tens to hundreds GHz.

Abstract: Disclosed is an operation principle and an epitaxial structure of resonant tunneling opto-electronic device. According to the present invention, the photo-generated holes stored in front of the double barrier quantum well structure by light illumination. As a result, a large potential drop occurs in the double barrier quantum well structure. And a peak signal of the opto-electronic resonant tunneling device is generated at a relatively lower voltage illumination to one generated before introducing the light into the device. An amount of photocurrent is 10.sup.3 times and over as compared to the conventional p-i-n diode because a resonant tunneling current is optically controlled by light illumination. So that, it is possible to drive peripheral circuit without use of additional amplifiers for amplifying an output signal from the opto-electronic device.