CN102074504B

CN102074504B - Method for manufacturing self-alignment thin film transistor (TFT) active matrix

Info

Publication number: CN102074504B
Application number: CN 201010561384
Authority: CN
Inventors: 陈龙龙; 李喜峰; 张建华
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2010-11-27
Filing date: 2010-11-27
Publication date: 2013-03-06
Anticipated expiration: 2030-11-27
Also published as: CN102074504A

Abstract

The invention relates to a micromachining process-based method for manufacturing a self-alignment TFT active matrix. In the method, an ohm contact layer is manufactured by adopting a self-alignment process, so the manufacturing process of the TFT active matrix is greatly reduced, and the manufacturing yield is improved. Difference from the traditional method for manufacturing the ohm contact layer in the TFT active matrix, the method realizes the manufacturing of the ohm contact layer by the self-alignment process, which means injecting ions from the metal electrode direction of a bottom grid and forming the ohm contact layers on an active layer and a source drain electrode layer by using the metal electrode of the bottom grid as a self-alignment graph, so the manufacturing process of the TFT active matrix is greatly reduced, and the manufacturing yield is improved.

Description

The manufacture method of self-alignment type tft active matrix

Technical field

The present invention relates to a kind of flat panel display and make the manufacture method in field, a kind of novel manufacturing method of tft active matrix specifically adopts the self-aligned manner of the method for miromaching and semiconductor technology to realize the making of tft active matrix.

Background technology

TFT is the abbreviation of Thin Film Transistor, and the Chinese meaning is thin-film transistor.

The manufacturing process flow of tradition tft active matrix following (see Fig. 1-Fig. 7):

(1) sputter bottom gate metal level on the TFT of cleaning glass substrate at first;

(2) by photoetching process the bottom gate metal level is made graphical treatment, obtain the figure of bottom gate thin film;

(3) successively deposition insulating layer, active layer and ohmic contact layer on the bottom gate metal level after graphical;

(4) ohmic contact layer and active layer are made graphical treatment, etching obtains the silicon island;

(5) sputter layer of metal electrode layer is as the source-drain electrode layer of tft active matrix;

(6) to the processing of source-drain electrode layer pattern, obtain the source metal electrode and leak metal electrode; And the ohmic contact layer at TFT raceway groove place made etching processing, ohmic contact layer disconnects herein;

(7) deposit one deck passivation protection layer, protection driven with active matrix module is avoided external environment to the impact of its performance; Make the electrode contact hole by etching.

Tradition tft active matrix manufacture craft process, ohmic contact layer on the active layer will be got rid of by the method for etching, because the ohmic contact layer thickness is very thin, therefore very high to the requirement of etching technics: the etching deficiency can cause the device active layer by short circuit, and device performance lost efficacy; Cross to carve and then can cause the device active layer to destroy, the performances such as the mobility of device all can be affected.Utilize this mode to make the tft active matrix difficulty very large, cost of manufacture is higher.

The present invention adopts the self-aligned manner of the method for miromaching and semiconductor technology to improve the manufacture method of tft active matrix ohmic contact layer, has reduced the manufacture difficulty of tft active matrix, has improved the rate of finished products of product; And after tft active matrix completes, can transfer on other glass substrate, glass substrate can be common glass substrate, but not is necessary for the TFT glass substrate, can greatly save manufacturing cost.

Summary of the invention

The objective of the invention is provides a kind of self-alignment type tft active matrix manufacture method based on miromaching for the defective that oneself has technology to exist, the method adopts the self-alignment type method to realize the making of ohmic contact layer, thereby the manufacturing process difficulty of tft active matrix is significantly reduced, improve fabrication yield.

According to the foregoing invention design, the present invention adopts following scheme:

A kind of self-alignment type tft active matrix manufacture method based on miromaching, the method for employing miromaching and the self-aligned manner of semiconductor technology are realized the manufacturing of tft active matrix, its processing step is as follows:

(1) heat growth one deck silicon oxide layer on the monocrystalline silicon wafer crystal of cleaning at first, the sacrifice layer that shifts as follow-up tft active matrix;

(2) at silicon oxide layer coating one deck resist layer, and one deck gate metal layer of growing thereon;

(3) gate metal layer is made graphical treatment, produce the bottom gate metal electrode of tft active matrix;

(4) on the bottom gate metal electrode of tft active matrix, grow insulating barrier, active layer, and active layer graph processed obtain the silicon island;

(5) the source-drain electrode layer of sputter tft active matrix, and make graphical treatment, obtain the source metal electrode and leak metal electrode;

(6) grown silicon nitride protective layer;

(7) again be coated with resist layer, and do planarization;

(8) utilize miromaching to etch away silicon oxide layer, the tft active matrix layer is peeled away on monocrystalline silicon wafer crystal;

(9) get rid of the resist layer that is coated with on the gate metal layer, and make Implantation from the direction of grid metal level, ion beam energy and dosage that control is injected form ohmic contact layer in self aligned mode, thereby active layer are connected with the source-drain electrode layer;

(10) the tft active matrix layer is transferred on the substrate: get rid of the resist layer on the source-drain electrode layer, and silicon nitride protective layer is made graphical treatment, etch the electrode contact hole, convenient follow-up lead-in wire.

So far finish based on the self-alignment type tft active matrix manufacture process of miromaching.

The described tft active matrix layer of above-mentioned steps (9) is transferred on the substrate, and the modes such as employing adhesive are adhered to the tft active matrix layer on the substrate; Substrate described herein can be common glass substrates, perhaps is the multiple substrates such as flexible base, board.

The present invention compared with prior art, have following apparent outstanding substantive distinguishing features and remarkable advantage: the present invention utilizes self-aligned manner to realize the making of ohmic contact layer, namely from bottom gate metal level electrode direction make Implantation and with the bottom gate metal electrode as self aligned figure, form ohmic contact layer at active layer and source-drain electrode layer, thereby the manufacturing process difficulty of tft active matrix is significantly reduced, improve fabrication yield.

Description of drawings

Fig. 1 ~ Fig. 7 is traditional tft active matrix manufacturing process flow diagram;

Fig. 8 is the self-alignment type tft active matrix manufacturing process block diagram based on miromaching of the present invention;

Fig. 9 ~ Figure 18 self-alignment type tft active matrix manufacturing process flow diagram based on miromaching of the present invention.

Embodiment

Below in conjunction with accompanying drawing the preferred embodiments of the present invention are described:

Embodiment 1: referring to Fig. 1 ~ Fig. 8, the present invention is based on the self-alignment type tft active matrix manufacture method of miromaching, the method for employing miromaching and the self-aligned manner of semiconductor technology are realized the manufacturing of tft active matrix.

At first at monocrystalline silicon wafer crystal 20 growth one deck silicon oxide layers 21 of cleaning, the follow-up stripping technology of micromachined that utilizes peels off the tft active matrix of making from monocrystalline silicon wafer crystal 20, and at silicon oxide layer 21 coating resist layers 22; Ensuing manufacturing process part is identical with the manufacturing process of traditional tft active matrix, several step process of deposit that comprise the deposit of gate metal layer 23 and graphical treatment, insulating barrier 24, active layer 25, be different from traditional tft active matrix and next make ohmic contact layer, the present invention does not make first ohmic contact layer herein temporarily, but growth source drain electrode layer 26 and graphical treatment, formation source, drain electrode; Follow grown silicon nitride protective layer 27, resist layer 28, and resist layer 28 is done planarization.

After each tunic structure growth completes, this step utilizes the stripping technology of the above-mentioned micromachined of mentioning that silicon oxide layer 21 is etched away, thereby tft active matrix and monocrystalline silicon wafer crystal 20 are separated, and resist layer 22 is got rid of, expose gate metal layer 23; Make Implantation from the direction of grid metal level 23, ion beam 30 energy and dosage that control is injected,, between active layer 25 and source-drain electrode layer 26, form ohmic contact layer 29, thereby active layer 25 is connected with source-drain electrode layer 26 as automatically accurate figure with the bottom gate metal electrode.

The tft active matrix layer is transferred on the substrate 40, got rid of the resist layer 28 on the source-drain electrode layer 26, and silicon nitride protective layer 27 is made graphical treatment, etch the electrode contact hole.

Self-alignment type tft active matrix manufacturing based on miromaching of the present invention is finished.

Embodiment 2: the present embodiment is substantially the same manner as Example 1, and special feature is: referring to Fig. 8 ~ Figure 18, choose the monocrystalline silicon wafer crystal 20 that 6 inches monocrystalline silicon wafer crystal is made as tft active matrix; At first utilize the SiO of method about monocrystalline silicon wafer crystal 20 growth a layer thickness are for 2mm of means of wet thermal oxidation ₂Layer is as silicon oxide layer 21; Utilize spin coater evenly to be coated with one deck organic film on silicon oxide layer 21, thickness is about about 1mm, and is heated to 130 ℃ and is cured processing; Then sputter gate metal layer 23 selects molybdenum/aluminum metal layer as gate metal layer, and metallic diaphragm thickness is about 2000; Gate metal layer 23 is carried out graphical treatment, it is spared after the techniques such as glue, photoetching, etching, obtain the bottom gate metal electrode 231 of gate metal layer 23; After gate metal layer 23 graphical treatment, by the method for PECVD, at the insulating barrier 24 of deposit about 3000 gradually on the gate metal layer 23, select silicon nitride or silica as insulating barrier 24, also the above-mentioned two kinds of double-deckers of optional usefulness are as insulating barrier 24; Growth one deck active layer 25 can select amorphous silicon or microcrystal silicon material as active layer 25, and deposition thickness is about 2500; Then sputter a layer thickness is about 3500 source-drain electrode layer 26, makes source metal electrode 261 after the graphical treatment, leaks metal electrode 262; Recycle afterwards PECVD deposit one deck silicon nitride protective layer 27, the thickness of deposit is about 2000, as the protective layer of source metal electrode 261, leakage metal electrode 262; Again adopting the mode of spin coating to be coated with a layer thickness is resist layer 28 about 1.5mm, be heated to 130 ℃ be cured process after and effects on surface do planarization; The one side that monocrystalline silicon wafer crystal 20 is not made device architecture adopts coating photoresist or alternate manner that it is protected.

The hf etching liquid of preparation 3%, the monocrystalline silicon wafer crystal 20 that is manufactured with tft active matrix is put into hf etching liquid, this kind method is the sacrifice layer etching technics in the miromaching, utilizes the method tft active matrix and monocrystalline silicon wafer crystal 20 can be peeled away; With liquid parting or organic solvent resist layer 22 is got rid of, exposed gate metal layer 23; Carry out Implantation from the direction of gate metal layer 23, control ion beam Implantation Energy is the 100KeV magnitude, the junction depth place of Implantation concentrates on the intersection of active layer 25 and source-drain electrode layer 26, gate metal layer 23 can blocks ions be injected into device inside herein, therefore play the autoregistration effect, thereby between active layer 25 and source-drain electrode layer 26, form ohmic contact layer 29, and ohmic contact layer 29 lays respectively at source metal electrode 261 and leaks metal electrode 262 belows, and two places are mutually discrete; Then be transferred to the tft active matrix layer on the substrate 40 and be fixed, the modes such as useful binders fix, and substrate can be selected and be common glass substrates, or the multiple substrate such as PET flexible base, board; Get rid of at last the resist layer 28 on the source-drain electrode layer 26, and silicon nitride protective layer 27 is made graphical treatment, etch the electrode contact hole, convenient follow-up lead-in wire.Thereby the manufacturing of tft active matrix layer finished.

Claims

1. a self-alignment type tft active matrix manufacture method is characterized in that, the method for employing miromaching and the self-aligned manner of semiconductor technology are realized the manufacturing of tft active matrix; Its manufacturing technology steps is as follows:

A. at first at the upper heat growth of the monocrystalline silicon wafer crystal (20) of cleaning one deck silicon oxide layer (21), as the sacrifice layer of follow-up tft active matrix transfer;

B. be coated with one deck resist layer (22) at silicon oxide layer (21), and one deck gate metal layer (23) of growing thereon;

C. gate metal layer (23) is made graphical treatment, produce the bottom gate metal electrode (231) of tft active matrix;

D. on the bottom gate metal electrode (231) of tft active matrix, grow insulating barrier (24), active layer (25), and active layer graph processed obtain the silicon island;

E. the source-drain electrode layer (26) of sputter tft active matrix, and make graphical treatment, obtain source metal electrode (261) and leak metal electrode (262);

F. grown silicon nitride protective layer (27);

G is coated with resist layer (28) again, and does planarization;

H. utilize miromaching to etch away silicon oxide layer (21), the tft active matrix layer is peeled away on monocrystalline silicon wafer crystal (20);

I. get rid of the resist layer (22) of the upper coating of gate metal layer (23), and make Implantation from the direction of grid metal level (23), ion beam (30) energy and dosage that control is injected, form ohmic contact layer (29) in self aligned mode, thereby active layer (25) is connected with source-drain electrode layer (26);

J. the tft active matrix layer is transferred on the substrate (40): get rid of the resist layer (28) on the source-drain electrode layer (26), and silicon nitride protective layer (27) is made graphical treatment, etch the electrode contact hole, convenient follow-up lead-in wire.

2. self-alignment type tft active matrix manufacture method according to claim 1 is characterized in that described tft active matrix layer transfers on the substrate, adopts adhesive means that the tft active matrix layer is adhered on the substrate.

3. self-alignment type tft active matrix manufacture method according to claim 1 is characterized in that described substrate is chosen as common glass substrates or is flexible base, board.