CN1801469A

CN1801469A - Chip packaging substrate gold finger and contact pad plating nickle gold process

Info

Publication number: CN1801469A
Application number: CN 200510000194
Authority: CN
Inventors: 方照贤; 林光华; 颜怡锋
Original assignee: Tripod Technology Corp
Current assignee: Tripod Technology Corp
Priority date: 2005-01-06
Filing date: 2005-01-06
Publication date: 2006-07-12

Abstract

The invention provides a manufacture method for first-order packaging substrate for application with different metal treatment on two surfaces (such as memory module card). Wherein, the main feature of this invention comprises: forming circuit on substrate top surface by acid etching; defining connecting finger part for electroplating on bottom surface of substrate by second image transfer; electroplating Ni/Au layer on connecting finger part and contact mat by turns. This invention can increase effective routing area of substrate and avoids noise interference.

Description

Chip packaging substrate gold finger and contact pad plating nickle gold process

Technical field

The present invention relates to the single order structure dress of integrated circuit (IC) chip, be particularly related to the single order structure and adorn a kind of manufacturing method thereof of used substrate, its outer surface at the golden finger of substrate and contact mat is electroplate with the processing procedure and the structure of one deck nickel gold, provides golden finger and contact mat good being electrically connected and the quality of abrasion performance.

Background technology

Integrated circuit (IC) chip must be integrated the competence exertion function through structure dress program and electronic system.In the industry of integrated circuit (IC) chip structure dress, generally the making with chip itself is called so-called zeroth order structure dress, the program that chip is installed to substrate (or claim support plate, substrate) or lead frame (lead frame) is called single order structure dress (primary level package), the chip that single order structure dress is finished is installed on the printed circuit board (PCB) of module or adapter and is called second order structure dress, and the process that at last module or adapter is installed to motherboard or system board is called three rank structures dresses.

Used substrate in the single order structure dress except being provided with fine and closely woven circuit, also has many electrical contact pads (or claim the I/O contact, similarly be bonding pad, bump pad, ball pad, contact pad etc.).These I/O contacts are coated with one deck nickel gold (Ni/Au) layer usually on the surface, with the stability of guaranteeing to be electrically connected with chip, or the copper unlikely oxidation of pad of protection metal.For on contact mat, plating this layer nickel-gold layer, must on substrate, arrange numerous electroplated leads in addition usually, the usefulness of conducting electric current during for plating.The layout of these electroplated leads not only occupies the area of substrate, also easily when structure dress high frequency chip, easily high frequency chip is caused interference of noise.Therefore, in recent years, industry has the basal plate making process method that proposes several so-called electroless plating leads (bussless), to solve the problem that layout was caused of electroplated lead.

Wherein, GPP a kind of by name (the Gold Pattern Plating) manufacturing method thereof that industry proposes is not lay the lead of electroplating usefulness in addition, but whole plated with nickel gold that on the circuit of substrate itself, (also therefore comprised all contact mats).Though this traditional technology has been avoided the laying of electroplated lead, but all there is the plated with nickel gold on the surface of all circuits, therefore production cost is quite high, in addition, the solder mask (solder mask) that is coated on substrate surface at last because of its material characteristic different with nickel-gold layer so that can not be stable combine.In addition in the Taiwan patent No. 515, disclosed another process technique in 061, this process technique is on the substrate that defines line layer, cover one deck conducting film, define the zone of I/O contact again with the mode of image transfer, with plating mode nickel-gold layer is plated on the surface of contact mat again, conducting film provides the conducting path of electric current when electroplating, and has therefore also avoided the laying of electroplated lead.Also has a kind of process technique, be to disclose in the Taiwan patent No. 538, in 152, this process technique is to lay a thin copper layer at substrate surface earlier, use the mode of secondary image transfer again, successively define the copper facing zone of circuit and the nickel plating gold zone of contact mat, photoresist and the thin copper layer with the secondary image transfer removes then, is coated with at last again and is covered with solder mask.

Though above-mentioned manufacturing method thereof has all been avoided the problem that nickel plating gold zone is excessive, nickel is golden to be contacted with the solder mask large tracts of land of GPP, all have process step too tediously long, be not suitable for the different shortcomings such as application of metal surface, substrate two sides processing procedure (metal finish).Indispensable small size flash cards (for example mmc card) such as the consumption electronic products of current trend such as digital camera, digital VTR, MP3 walkman, electronic dictionary, PDA, multimedia handset for example, its one side at substrate has the golden finger as plug, another side at substrate has the purposes (wire bonding) of electrical contact pad as wire bond, and traditional electroless plating lead process technique also is not suitable for this series products.

Summary of the invention

Main purpose of the present invention provides a kind of manufacturing method thereof of single order structure installation plate, and this manufacturing method thereof is applicable to the application (for example structure of mmc card dress) that needs the substrate two sides that the different metal processing procedure is arranged.

The topmost feature of manufacturing method thereof proposed by the invention is to comprise the following steps: to provide a substrate at least, and the upper and lower surface of this substrate has been laid a line layer respectively, and has a plurality of vias; At the upper surface of this substrate, for the first time image transfer program and an acid etching program form a conductor line with one; At the lower surface of this substrate, with an image transfer program and define a golden finger zone that needs the nickel plating gold for the second time; Mode to electroplate plates one first nickel-gold layer in this golden finger zone; Remove the photoresist of this of image transfer second time; With an image transfer program for the third time, and an alkali etching program and define a contact mat zone that needs the nickel plating gold; And the mode to electroplate, in this contact mat zone, plate one second nickel-gold layer.

Manufacturing method thereof proposed by the invention plates nickel-gold layer in the mode of electroless plating lead on contact mat and golden finger, can increase the substrate surface area that effectively connects up, and avoids the noise jamming that causes because lay electroplated lead simultaneously.

Manufacturing method thereof proposed by the invention can be avoided the nickel gold shortcoming that area is excessive, flow process is tediously long, reliability is low of conventional art.

The detailed description and the claim scope that now cooperate appended icon, embodiment, will on address other purpose of the present invention and advantage and be specified in after.Yet, just establish the improper definition that is considered as category of the present invention for explaining orally spirit of the present invention when understanding appended icon.The definition of relevant category of the present invention please refer to appended claim.

Description of drawings

Fig. 1 to Fig. 6 is a cross-sectional view of implementing metacoxal plate according to each step of the present invention.

Among the figure

110 substrates, 110 line layers

112 conductor lines, 114 nickel-gold layers

116 nickel-gold layers, 130 vias

Embodiment

Relevant the specific embodiment of the present invention sees also Fig. 1.Fig. 1 is the cross-sectional view of each step of the present invention.

One substrate 100 at first is provided, and as shown in Figure 1a, the upper and lower surface of this substrate 100 has been laid with line layer 110 respectively, and has some vias 120.

Then at the upper surface of substrate 100, form conductor line 112 in the mode of dry film (dry film) or liquid photoresist image transfer and acid etching, its result is as shown in Figure 2.

Then, at the lower surface of substrate 100, carry out the image transfer second time in the mode of dry film (dry film) or liquid photoresist equally, need the golden finger of nickel plating gold zone to define, its result as shown in Figure 3.

Then, the mode to electroplate is utilized the conducting of line layer 110 as electroplating current again, and the golden finger zone in that previous step defined out plates nickel-gold layer 114, and its result as shown in Figure 4.Note that on conducting hole wall and the conductor line 112 that partly is communicated with and also be coated with nickel-gold layer.

The photoresist that flow process is then incited somebody to action the image transfer second time removes, and carries out image transfer for the third time in the mode of dry film (dry film) or liquid photoresist again, and forms the contact mat zone that needs the nickel plating gold with alkali etching, and its result as shown in Figure 5.

Then, in the mode of plating, the contact mat zone in that previous step defined out plates nickel-gold layer 116 again, and its result as shown in Figure 6.Last impressing patternization again solder mask to finish the making of this substrate.

By the above detailed description of preferred embodiments, hope can be known description feature of the present invention and spirit more, and is not to come category of the present invention is limited with above-mentioned disclosed preferred embodiment.On the contrary, its objective is that hope can contain in the category of claim of being arranged in of various changes and tool equality institute of the present invention desire application.

Claims

1. chip packaging substrate gold finger and contact pad plating nickle gold process comprise the following steps: at least

One substrate is provided, and the upper and lower surface of this substrate has been laid a line layer respectively, and has a plurality of vias;

At the upper surface of this substrate, for the first time image transfer program and an acid etching program form a conductor line with one;

At the lower surface of this substrate, with an image transfer program and define a golden finger zone that needs the nickel plating gold for the second time;

Mode to electroplate plates one first nickel-gold layer in this golden finger zone;

Remove the photoresist of this of image transfer second time;

With an image transfer program for the third time, and an alkali etching program and define a contact mat zone that needs the nickel plating gold; And

Mode to electroplate in this contact mat zone, plates one second nickel-gold layer.

2. plating nickle gold process as claimed in claim 1, wherein, this first, second, third image transfer is to adopt dry film photoresist mode.

3. plating nickle gold process as claimed in claim 1, wherein, this first, second, third image transfer is to adopt the liquid photoresist mode.