Method for preparing optical communication window rare earth film superlattice luminescent material

Abstract

The invention discloses a method for preparing an optical communication window rare earth film superlattice luminescent material by depositing short pulse laser on a silicon wafer, which comprises the following steps of: respectively acting on Si, Yb or Er target materials in high vacuum of a pulse laser deposition cavity by utilizing the short pulse laser, and sputtering onto a semiconductor P-type silicon wafer on a sample table; the preparation method comprises the following steps: preparing a film layer with a nano thickness by adjusting sputtering time, sequentially preparing a multi-layer nano film through laser sputtering, constructing a multi-layer superlattice structure of an Er-Yb film, and capping by using a Si material, the near-infrared laser beam spots are expanded to uniformly distributed round spots with the diameter of 1cm through a beam expanding and collimating light path, and the round spots act on a silicon wafer for laser annealing treatment; the prepared sample is placed on an infrared fluorescence detector for measurement and characterization of luminescence characteristics, strong luminescence peaks are detected at 1325nm and 1550nm at normal temperature, and 532nm continuous laser is adopted as excited laser.

Description

Technical Field

[0001] The invention relates to the field of semiconductor science and technology, and in particular to a method for preparing a rare earth thin film superlattice luminescent material for an optical communication window. Background Art

[0002] Over the past 20 years, we have been experiencing a transition from the electronic information age to the photonic information age. The invention of fiber erbium-doped amplifiers and Raman amplifiers has promoted the realization of all-optical network communications. Currently, we are experiencing a critical development stage of on-chip and off-chip interconnection integration of silicon-based photonics. The research and development and application of integrated optical communication window lasing materials and devices on silicon wafers are particularly important. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for preparing rare earth thin film superlattice luminescent materials for optical communication windows. The preparation method adopts a purely physical laser preparation process and is green and environmentally friendly. The rare earth thin film superlattice luminescent materials and devices prepared by the preparation method have good luminescence in the second and third windows of optical communication, and can promote the research and development and industrial development of silicon-based optical communication integrated chips.

[0004] The present invention is implemented as follows: a method for preparing optical communication window rare earth thin film superlattice luminescent material on silicon wafer by short pulse laser deposition, characterized in that: short pulse laser is used to act on Si, Yb or Er target materials respectively in the high vacuum of pulse laser deposition chamber, sputtered onto semiconductor P-type silicon wafer on sample stage, a film layer with nanometer thickness is prepared by adjusting sputtering time control, multilayer nanofilm is prepared by laser sputtering in sequence, Er-Yb film multilayer superlattice structure is constructed, and then capped with Si material; near infrared laser beam spot is expanded to a circular spot with a diameter of 1 cm and evenly distributed through beam expansion and collimation optical path, and acted on silicon wafer for laser annealing treatment to obtain optical communication window rare earth thin film superlattice luminescent material. The sample prepared by this method is placed on infrared fluorescence detector to measure and characterize the luminescent characteristics, and strong luminescent peaks are detected on the sample at 1325nm (optical communication second window) and 1550nm (optical communication third window) at room temperature.

[0005] The short pulse laser is a femtosecond, picosecond or nanosecond laser of 355nm (or other wavelengths), with an average power of 5-20W and a repetition rate of 3-30K / s.

[0006] The wavelength of the near-infrared laser is 1064 nm (or other near-infrared wavelengths).

[0007] The high vacuum of the laser deposition chamber is 10 -5 Pa.

[0008] The temperature of the laser annealing is 900° C., the annealing time is 20 to 30 minutes, and the annealing atmosphere is an oxygen blowing environment.

[0009] The sample prepared by the above method was placed on an infrared fluorescence detector to measure and characterize the luminescence characteristics. At room temperature, strong luminescence peaks were detected on the sample at 1325nm (the second window of optical communication) and 1550nm (the third window of optical communication). The luminescence spectrum and power spectrum in the second window of optical communication are shown in Figure 2. Figure 3 As shown, 532nm continuous laser excitation is used in the measurement. It can be used for the research and development of luminescent materials and devices for silicon-based integrated optical communication windows and industrial development. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 The structural diagram of the preparation principle of the method for preparing rare earth thin film superlattice luminescent materials for optical communication windows on silicon wafers using short pulse laser deposition;

[0011] Figure 2 Schematic diagram of laser annealing crystal growth;

[0012] Figure 3 Variable power luminescence peak (a) and power spectrum curve (b) detected at 1325nm (second optical communication window) at room temperature;

[0013] Figure 4 A structural diagram of a three-layer superlattice structure of Er-Yb films prepared by laser sputtering on a silicon substrate and then capped with Si material. DETAILED DESCRIPTION

[0014] Example 1 of the present invention: Using ultraviolet (355nm) short pulse nanosecond laser (average power: 5W, repetition rate per second: 20K / s) in a high vacuum (10 -6 Pa) acts on Si, Yb or Er target materials respectively, and sputters onto the semiconductor P-type silicon wafer on the sample stage. By adjusting the sputtering time, a film layer with a nanometer thickness is prepared. Multilayer nanofilms are prepared by laser sputtering in sequence to construct a 3-layer superlattice structure of Er-Yb film, and then capped with Si material. The structure diagram is shown in the figure Figure 4 As shown; the near-infrared (1064nm) laser beam spot is expanded to a uniformly distributed circular spot with a diameter of 1 cm through the expansion and collimation optical path, and is applied to the silicon wafer for laser annealing. The temperature of the silicon wafer is controlled at 900°C with a remote-controlled thermometer. The annealing time is 20 minutes and the annealing atmosphere is an oxygen-blown environment. The prepared sample is placed on an infrared fluorescence detector to measure and characterize the luminescence characteristics. At room temperature, stronger luminescence peaks are detected on the sample at 1325nm and 1550nm, and the excitation laser uses a 532nm continuous laser.

[0015] Embodiment 2 of the present invention: Infrared (1064 nm) short pulse nanosecond laser (average power: 40 W, repetition rate per second: 40 K / s) is used in a high vacuum (10 -6 Pa) acts on Si, Yb or Er target materials respectively, and sputters them onto semiconductor P-type silicon wafers on the sample stage. A film layer with a nanometer thickness is prepared by adjusting the sputtering time control, and multi-layer nano-thin films are prepared in sequence by laser sputtering to construct a 6-layer superlattice structure of Er-Yb film, which is then capped with Si material; the near-infrared (1064nm) laser beam spot is expanded to a circular spot with a diameter of 1 cm and evenly distributed through a beam expansion and collimation optical path, and acts on a silicon wafer for laser annealing treatment. The temperature of the silicon wafer is controlled at 1000°C by a remote-controlled thermometer, the annealing time is 30 minutes, and the annealing atmosphere is an oxygen blowing environment; the prepared sample is placed on an infrared fluorescence detector to measure and characterize the luminescence characteristics, and strong luminescence peaks are detected at 1325nm and 1550nm at room temperature, and the excitation laser uses a 532nm continuous laser.

Claims

1. A method for preparing a rare earth thin film superlattice luminescent material for an optical communication window on a silicon wafer by short pulse laser deposition, characterized in that: A short pulse laser is used to act on Si, Yb or Er target materials in the high vacuum of a pulsed laser deposition chamber, and then sputtered onto a semiconductor P-type silicon wafer on a sample stage. A film layer with a nanometer thickness is prepared by adjusting the sputtering time control, and multiple layers of nano-thin films are prepared by laser sputtering in turn to construct an Er-Yb film multilayer superlattice structure, which is then capped with Si material. The near-infrared laser beam spot is expanded to a uniformly distributed circular spot with a diameter of 1 cm through a beam expansion and collimation optical path, and then acted on a silicon wafer for laser annealing to obtain a rare earth thin film superlattice luminescent material for an optical communication window.

2. The method for preparing a rare earth thin film superlattice luminescent material for an optical communication window on a silicon wafer by short pulse laser deposition according to claim 1, characterized in that: The short pulse laser is a femtosecond, picosecond or nanosecond ultraviolet or infrared pulse laser, with an average power of 5 to 20W and a repetition rate of 3 to 30K / s.

3. The method for preparing a rare earth thin film superlattice luminescent material for an optical communication window on a silicon wafer by short pulse laser deposition according to claim 1, characterized in that: The near-infrared laser beam spot is expanded to a uniformly distributed circular spot with a diameter of 1 cm through a beam expansion and collimation optical path, and acts on the silicon wafer for laser annealing.

4. The method for preparing a rare earth thin film superlattice luminescent material for an optical communication window on a silicon wafer by short pulse laser deposition according to claim 1, characterized in that: The high vacuum of the laser deposition chamber used is 10 -6 Pa.

5. The method for preparing a rare earth thin film superlattice luminescent material for an optical communication window on a silicon wafer by short pulse laser deposition according to claim 1, characterized in that: The laser annealing temperature is 900° C., the annealing time is 20 to 30 minutes, and the annealing atmosphere is an oxygen blowing environment.

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