CN105047603A - Processing method for hybrid bonding metal protruded interface - Google Patents

Abstract

The invention relates to a treatment method for the protruding interface of mixed bonding metals. The method includes the following steps: providing a wafer to be processed, forming a silicon nitride layer on the surface of the wafer, depositing a thin film layer on the silicon nitride layer; coating the upper surface of the thin film layer with photoresist, and adopting photolithography, The etching method forms grooves in the thin film layer and the silicon nitride layer; the metal deposition method is used to deposit metal to fill the groove and cover the upper surface of the thin film layer; the chemical mechanical polishing method is used to remove the metal copper and part of the thin film layer on the surface of the thin film layer , to ensure that all the metal copper above the trench is removed; etch the thin film layer to obtain a metal protruding interface between the thin film layer and the metal; continue to etch until the etching stops at the silicon nitride layer to obtain the silicon nitride layer and the metal Metallic protruding interfaces between metals. The invention can solve the difficulty that the metal protruding bonding surface cannot be produced by chemical mechanical grinding due to the hardness of the insulating substance, and has a good effect.

Description

A kind of hybrid bonded metal gives prominence to the processing method at interface

Technical field

The present invention relates to field of semiconductor manufacture, be specifically related to the processing method that a kind of hybrid bonded metal gives prominence to interface.

Background technology

When very lagre scale integrated circuit (VLSIC) development is day by day close to physics limit, the three dimensional integrated circuits all in physical size and cost aspect with advantage is the effective way extending Moore's Law and solve Advanced Packaging problem.And one of wafer bond techniques key technology that three-dimensional circuit is integrated just, especially hybrid bonded technology can realize the interconnected of thousands of chip while two panels wafer bonding, greatly can improve chip performance and cost-saving.Hybrid bonded technology refers to bonding pattern wafer bonding interface existing simultaneously metal and megohmite insulant.

There is metal and megohmite insulant in hybrid bonded surface, produce metal and to give prominence to or the bonded interface that caves in effectively can lower the requirement of bonding effects on surface flatness simultaneously.But when megohmite insulant is harder, be difficult to obtain the outstanding interface of metal by traditional chemical and mechanical grinding method.

Summary of the invention

The object of this invention is to provide a kind of process for treating surface, give prominence to bonding surface to manufacture metal required in hybrid bonded technology.

For solving the problems of the technologies described above, the invention provides the processing method that a kind of hybrid bonded metal gives prominence to interface, comprising the steps:

Step one, provide a pending wafer, described crystal column surface is formed with a silicon nitride layer, deposit one thin layer on described silicon nitride layer;

Step 2, coating photoresist covers the upper surface of described thin layer, adopts photoetching successively, lithographic method forms groove in described thin layer and silicon nitride layer;

Step 3, utilizes metal deposition depositing metal to fill described groove and covers described thin layer upper surface;

Step 4, utilizes chemical and mechanical grinding method to remove the metallic copper of described thin-film surface and the thin layer of part, guarantees that the metallic copper above described groove is all removed;

Step 5, etches described thin layer, and the metal obtained between described thin layer and metal gives prominence to interface; Continue etching, etching terminates in described silicon nitride layer, and the metal obtained between described silicon nitride layer and metal gives prominence to interface.

Preferably, the material of described thin layer is silicon dioxide or carborundum.

The invention has the beneficial effects as follows: the present invention's hardness can ignored due to megohmite insulant is brought, and cannot manufacture by conventional art (as cmp) difficulty that metal gives prominence to bonding surface.

Accompanying drawing explanation

Fig. 1 to Fig. 6 is the processing method embodiment flow process generalized section that a kind of hybrid bonded metal of the present invention gives prominence to interface.

In accompanying drawing, the list of parts representated by each label is as follows:

1, wafer, 2, silicon nitride layer, 3, thin layer, 4, metal.

Embodiment

Be described principle of the present invention and feature below in conjunction with accompanying drawing, example, only for explaining the present invention, is not intended to limit scope of the present invention.

There is metal and megohmite insulant in hybrid bonded surface, produce metal and to give prominence to or the bonded interface that caves in effectively can lower the requirement of bonding effects on surface flatness simultaneously, but when the megohmite insulant on hybrid bonded surface is harder, be difficult to obtain mixed bond wire by traditional chemical and mechanical grinding method and give prominence to interface, the present invention deposits the softer film of one deck (during as process silicon nitride and metal surface on pending crystal column surface megohmite insulant, in silicon nitride surface deposition layer of silicon dioxide), carry out traditional metal rear end interconnection technology afterwards again, when in the end carrying out surface treatment, first obtain metal and give prominence to interface compared with the metal between flexible film, find the critical point exhausted by film again, namely the metal produced between metal-insulator material gives prominence to interface, thus the hardness can ignored due to megohmite insulant is brought, and cannot manufacture by conventional art (as cmp) difficulty that metal gives prominence to bonding surface.

Fig. 1 to Fig. 6 is the processing method embodiment process structure schematic diagram that a kind of hybrid bonded metal of the present invention gives prominence to interface, and as shown in Figures 1 to 6, a kind of hybrid bonded metal gives prominence to the processing method at interface, comprises the steps:

Step one, provide a pending wafer 1, wafer 1 surface is formed with a silicon nitride layer 2, deposit one thin layer 3 on silicon nitride layer 2; The material of thin layer 3 is silicon dioxide or carborundum;

Step 2, the upper surface of coating photoresist cover layer 3, adopts photoetching successively, lithographic method forms groove in thin layer 3 and silicon nitride layer 2;

Step 3, utilizes metal deposition depositing metal 4 filling groove and cover layer 3 upper surface;

Step 4, utilizes chemical and mechanical grinding method to remove the metallic copper on thin layer 3 surface and the thin layer 3 of part, guarantees that the metallic copper above groove is all removed;

Step 5, etches thin layer 3, and the metal obtained between thin layer 3 and metal gives prominence to interface; Continue etching, etching terminates in silicon nitride layer 2, and the metal obtained between silicon nitride layer 2 and metal gives prominence to interface.

The above implementation step and method only have expressed one embodiment of the present invention, describe comparatively concrete and detailed, but therefore can not be interpreted as the restriction to the scope of the claims of the present invention.Under the prerequisite not departing from inventional idea of the present invention, the distortion done and improvement all should belong to the protection range of patent of the present invention.

Claims (2)

1. hybrid bonded metal gives prominence to the processing method at interface, it is characterized in that, comprises the steps:

Step one, provide a pending wafer, described crystal column surface is formed with a silicon nitride layer, deposit one thin layer on described silicon nitride layer;

Step 2, coating photoresist covers the upper surface of described thin layer, adopts photoetching successively, lithographic method forms groove in described thin layer and silicon nitride layer;

Step 3, utilizes metal deposition depositing metal to fill described groove and covers described thin layer upper surface;

Step 4, utilizes chemical and mechanical grinding method to remove the metallic copper of described thin-film surface and the thin layer of part, guarantees that the metallic copper above described groove is all removed;

Step 5, etches described thin layer, and the metal obtained between described thin layer and metal gives prominence to interface; Continue etching, etching terminates in described silicon nitride layer, and the metal obtained between described silicon nitride layer and metal gives prominence to interface.

2. a kind of hybrid bonded metal gives prominence to the processing method at interface according to claim 1, it is characterized in that, the material of described thin layer is silicon dioxide or carborundum.