A high-temperature icp etching method for aluminum-containing materials in high-speed dfb chips

Abstract

The invention relates to a high-temperature ICP etching method for aluminum-containing materials in a high-speed DFB chip, which comprises the following steps: (1) cleaning the surface of a chip source that has a grating pattern and has been buried and grown by metal-organic chemical vapor phase epitaxy; (2) ) put the surface-cleaned film source into PECVD to grow a mask layer; (3) perform ridge pattern photolithography on the film source with a mask layer after photolithography uniform glue; (4) use reactive ion etching The equipment (RIE) transfers the photoresist pattern after exposure and development to the mask layer; (5) removes the photoresist on the surface of the film source after RIE etching; (6) transfers the film source containing the mask layer pattern Put it into an ICP etching machine that has been heated to a predetermined temperature for dry etching. The high-temperature ICP etching method for aluminum-containing materials provided by the present invention has less polymer on the surface after etching, and the etched appearance is smooth without protrusions, which solves the problem of slow etching rate and poor etching of aluminum-containing materials during the etching process. The problem that the morphology is difficult to control, so as to ensure that the PN burying process of the BH structure high-speed laser chip is normal.

Description

technical field [0001] The invention relates to the field of information optoelectronics, and relates to a high-temperature ICP etching method for aluminum-containing materials in a high-speed DFB chip, in particular to an inductively coupled plasma etching machine (ICP) for etching an ICP-based semiconductor high-speed DFB laser chip. Aluminum-containing materials (AlGaInAs) method. Background technique [0002] The 21st century belongs to the era of high informationization, such as the storage and sharing of data center databases, the wide application of artificial intelligence systems, and the development of the information age is based on the rapid transmission of communication networks. Therefore, the relevant research on high-speed laser chips with high modulation frequency bandwidth is the mainstream of optical communication research at this stage. [0003] In the early research process of the laser chip, the active region material is mainly based on the InGaAsP / lnP ...

AI Technical Summary

Problems solved by technology

Under the conditions of existing RIE and ICP etching equipment and etching gases such as Cl2, CH4, H2, Ar, etc. used for etching InP systems, it is difficult to control the etching morphology for dry etching of materials containing aluminum systems. There are a series of problems such as etching dirt residue, and the oxidation etching rate of the aluminum-containing active area is slow during the etching process.

In order to ensure the verticality of the etching morphology of the ridges, the etching process is non-selective etching, and for the common InP system etching gas, it is easier to etch the InP layer, and the etching of the aluminum-containing active region layer is slow, so that It is easy to appear that the aluminum-containing active region layer protrudes after etching, and the etching morphology is not vertical. In this case, the concentration of etching InP reaction ions can be reduced by increasing the etching power and increasing the concentration of physical bombardment ions, or increasing a variety of Etching gas matching, such as increasing the proportion of Ar, H2, reducing the proportion of Cl2, or matching etching with multiple etching gases such as Cl2, H2, CH4, BCl3, etc., but due to the extremely poor volatility of the etching product InClx, reducing The concentration of etching ions and the introduction of more etching gas will easily cause the etching polymer to be more difficult to remove, forming polymer residue, and the etching surface is dirty.

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