Process for integrated lens obtaining

The invention refers! to optoelectronic !, particularly to monolithic optical devices based on semiconductors and can be used! as a coupling element for light sources and receivers! at the guides!

There are known procedures for obtaining integrated lenses with waveguides! [1], based on the creation of a portion of the wave guide! for certain! form! through planar deposition! or chemical pickling! and the posterior heat treatment to obtain the lenses of certain о! form !. Such a procedure is especially applicable for the waveguides! made of glass! and even more for semiconductors. Another shortcoming of the known processes is the heat treatment at high temperatures, which can lead to changing the parameters of the forming semiconductor layers! the integrated optical circuit or the deterioration of the already formed devices, as well as the difficulty of controlling the lens configuration.

There is also known a process for obtaining lenses, preferably from III-V semiconductors [2], based on obtaining a precursor of the shaped lens! of table-structure! multi-level formed by chemical pickling! of a substrate and the thermal treatment of the structure in the presence of a flow of protective gases, which leads to the transport of III-V material in a quantity and direction, which ensure! profile required. The shortcoming of this procedure is const! in the heat treatment at high temperatures, which can lead to the change of the parameters of the semiconductor layers forming! the integrated optical circuit or the deterioration of the already formed devices, as well as the difficulty of controlling the lens configuration.

There is also known a process for obtaining lenses integrated into monolithic optical devices based on semiconductors [3], formed by changing the refractive index of the core of the waveguide. by changing the thickness of a portion of the forming layer! the core of the guide! The shortcoming of this process is the need to form three-dimensional structures whose configuration is difficult to control.

The problem I solve! invention const! in the realization of a process of obtaining the integrated lenses based on the semiconductor layers, which would allow the formation of a planar structure with an easily controllable configuration!

The essence of the invention is const! in the fact that! on the surface of a semiconductor layer is deposited о mask! with a hole that determines! lens shape, then implant! High energy ions! and it is done! electrochemical pickling !.

The result of the invention is const! in obtaining a lens integrated in monolithic optical devices on semiconductors with easily controllable parameters.

The invention is explained! through the figure in the drawing, which represent! overview of the integrated lens.

Example of carrying out the invention

The process of obtaining the integrated lens includes the following technological phases:

I. Deposition on one of the surfaces of a semiconductor substrate 1 of a mask 2.

II. High energy ion implantation! on the porch not covered! pet! 3.

III. Formation of a porous structure on the porphyry with implantafion ions by electrochemical pickling!

In this example, a layer of η-GaP was used with orientation (100) and electron concentration at the earner temperature! equal! with (3 ... 10) xl0¹⁷ cm³.

О masc has been deposited! metal! out of shape! it! tat! in drawing with dimensions d = 1 mm; R = 1 mm.

For ion implantation, the semiconductor layer is subjected to electrochemical pickup over 45 .. .90 min, in a solution of 0.5 MH₂SO₄/ H₂Oh, at the potential difference of 5 V, up! when forming pores with a diameter of 100 mm.

Lens obtained! through this process it has focal length! equal! by 1 mm. By changing the configuration you know we can obtain the lenses with different focal lengths, according to the formula: F = R²/ D. The lens parameters can also be varied by changing the porosity of the lens, changing the ion implantation dose or electrochemical parameter pickling.