Flying type optical head integrally formed with light source and photodetector and optical disk apparatus with the same

A method of manufacturing an optical head wherein a semiconductor laser and a photodetector are formed via a buffer layer on the same substrate in such a manner that a laser light emitting surface of the semiconductor laser and a light receiving surface of said photodetector are directed to the same direction, and an opening is fabricated under said laser emitting surface and said light receiving surface by an etching process, comprising the steps of:

• stacking a first transparent layer used to fill said opening by way of the plasma CVD (chemical vapor deposition) and sputtering processes;
• forming a diffraction grating on a lower surface of said first transparent layer by way of the photomask exposure process;
• stacking a second transparent layer under said first transparent layer by way of the plasma CVD, and sputtering processes;
• and
• forming either a grating lens on a lower surface of said second transparent layer by way of the photomask exposure process, or one of a distributed index lens and a convex lens on said lower surface of said second transparent layer by way of the disk apparatus.

An optical disk apparatus comprising:

• a flying type optical head whose flying amount is smaller than, or equal to 26 micrometers;
• an optical disk having no transparent protection layer on the information reading side of the recording surface thereof, or having a transparent protection layer with a thickness less than a value obtained by subtracting said flying amount from a back focus distance of an object lens located within a medium whose refractive index is 1.0, and by multiplying the subtraction result by a refractive index of a protection layer;
• a supporting mechanism for supporting said optical head;
• and
• a dust-guard cartridge for containing at least said optical disk, said optical head, and said supporting mechanism.

An optical disk apparatus comprising:

• an optical disk having no transparent protection layer at the information reading side of the recording surface thereof, or having a transparent protection layer with a thickness less than 26 micrometers;
• a supporting mechanism for supporting said optical head;
• and
• a dust-guard cartridge for containing said optical disk, said flying type optical head, and said supporting mechanism.

A method of manufacturing an optical head in which a surface emitting laser and a photodiode are manufactured at the same time in accordance with the following processing steps (a) to (f), comprising the steps wherein:

• (a) an n type AlGaAs buffer layer is grown on an n type GaAs substrate, an n+ type GaAs layer is grown on said buffer layer, and a first reflection mirror layer constructed by alternately stacking n type AlAs layers and GaAlAs layers is formed on said n+ type GaAs layer;
• (b) said first reflection mirror layer is removed by way of an etching process only from a portion where said photodiode is to be manufactured, and an n type AlGaAs layer is grown on the layer removed portion;
• (c) an n type AlGaAs clad layer is formed on said first reflection mirror layer and said n type AlGaAs layer, a p type GaAlAs quantum well layer is grown on said clad layer as an activate layer, a p type GaAlAs clad layer is fabricated on said activate layer, and a second reflection mirror layer constructed by alternately sacking n type AlAs layers and GaAlAs layers is grown on said clad layer;
• (d) said second reflection mirror layer is removed by way of the etching process only from the portion where the photodiode is to be formed, and a p type GaAs layer is formed on the removed portion;
• (e) a p+ type GaAs layer is formed on said second reflection mirror layer and said p type GaAs layer, on which an Au electrode is formed;
• and
• (f) a groove for separating said surface emitting laser from said photodiode is formed.

An optical head:

• wherein
• a semiconductor laser is formed via a buffer layer on a substrate, and an opening portion is fabricated in the substrate at a lower portion of a laser emitting surface;
• wherein
• said opening portion is furthermore filled with a transparent layer;
• and wherein
• one of a grating lens, a distributed index lens, and a condenser lens made of a convex lens having a diameter less than 1 mm is formed on a lower surface of said transparent layer.