Semiconductor element with a silicon layer

Details Semiconductor element with a silicon layer Semiconductor element with a silicon layer

1992-12-02

1994-01-18

Jackson, Jerome

Active solid-state devices (e.g., transistors, solid-state diode

Responsive to non-electrical signal

Electromagnetic or particle radiation

257184, 359248, 385 2, 385 14, H01L 29165, H01L 3100

Patent

active

052801896

DESCRIPTION:

BRIEF SUMMARY
The invention relates to an optoelectronic semiconductor element with a silicon layer, with an optical waveguide containing silicon in the region of a surface of the silicon layer, and with a diode structure connected with external, conductive contacts in the region of the same surface of the silicon layer, in such an arrangement to the waveguide that the diode structure can be influenced by electron hole pairs generated by photons in the waveguide.
In a known semiconductor element of this type ("IEEE Electron Device Letters," Col. EDL-7, No. 5, May 1986, p. 330-332), an optical wave is guided in an absorbent waveguide, which is arranged in the region of a surface of a silicon layer and composed alternately of silicon and germanium/silicon layers. For the waveguide, a diode structure connected with external contacts is provided, in such an arrangement that the diode structure can be influenced in its electrical conductivity by means of electron hole pairs generated by photons in the waveguide. The waveguide is surrounded by layers with high doping. The high doping leads to high losses due to the absorption of free charge carriers. The known semiconductor element is therefore unsuitable for use as a component representing a combination of an integrated waveguide with a photodetector.
The invention is therefore based on the task of indicating an optoelectronic semiconductor element on the basis of silicon, which contains a low-loss optical waveguide and is therefore well suited for optical-electrical conversion.
To accomplish this task, the waveguide in a semiconductor element of the type stated initially is weakly doped, avoiding high losses due to free charge carriers, and a germanium-rich layer which gives off the electron hole pairs and is arranged adjacent to the waveguide is a component of the diode structure.
While it is known from the publication "Monolithic Integration of Photodiodes and Buried Stripe Waveguides on InP" by R. Kaiser et waveguide and is, therefore, well suited for optical-electrical conversion.


SUMMARY OF THE INVENTION

This and other needs are satisfied by the semiconductor element of the present invention. The waveguide in a semiconductor element similar to the one described above is weakly doped avoiding high losses due to free charge carriers. A germanium-rich layer, which gives off electron hole pairs and is arranged adjacent to the waveguide, is a component of the diode structure.
In the publication "Monolithic Integration of Photodiodes and Buried Stripe Waveguides on InP" by R. Kaiser et al., in Proceedings, 15th European Conference on Optical Communication, Vol. 1 Sep. 1989, p. 360-363, a semiconductor element is provided which contains a waveguide and a photodetector. This semiconductor element is essentially composed of III/V semiconductors. Therefore, these semiconductors involve semiconductor materials which are very complicated to structure, so that this semiconductor element is relatively complicated in production.
A significant advantage of the semiconductor element according to the present invention is that it can be produced over a wide-spread silicon material, and therefore can be produced in a relatively inexpensive manner. In a silicon material, high losses due to free charge carriers are avoided due to the weak doping of the optical waveguide. In this connection, the germanium content in the germanium-rich layer is selected in such a way that the band distance becomes sufficiently small so that photons in the optical waveguide lead to electron hole pairs in the germanium-rich layer, which results in separation of the electrons and the holes by the combination of the germanium-rich layer and the diode structure.
In the semiconductor element according to the invention, it is advantageous if the diode structure in an optical waveguide, located at a surface of the semiconductor element, extends perpendicular to the waveguide in the region of this surface of the silicon layer. Such a structure has the advantage that damping of the optical wave at the metal of the e

REFERENCES:
patent: 5107538 (1992-04-01), Benton et al.

Affiliated with

Also associated with

Rating

Semiconductor element with a silicon layer does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Semiconductor element with a silicon layer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiconductor element with a silicon layer will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1138000