金属化陶瓷基板是一种电路板，其热膨胀系数接近半导体，耐热性高，适用于发热量大的产品（高亮度LED、太阳能），其优异的耐候性更适合户外恶劣环境，因其具有无铅、无毒、化学稳定性好等特点，不会对环保造成危害，因此越来越被大众广泛接受。

由于工艺不同，陶瓷基板主要分为DBC（直接覆铜）、DPC（直接镀铜）、AMB（活性金属钎焊）、厚膜等。

我们将逐一介绍这些工艺，并介绍每种工艺的优缺点。

DBC（直接覆铜）

由陶瓷基板、粘结层、导电层组成，是指在高温下将铜箔直接粘结到氧化铝或氮化铝陶瓷基板表面的特殊工艺。

优点：

• 铜层厚；
• 加工速度快；
• 价格便宜；
• 可做多层；
• 适合大面积使用；
• 热导率高；
• 附着强度高；
• 软钎焊性好；
• 电绝缘性好

缺点：

• 不能过孔；
• 精度差；
• 平整度（表面粗糙度）低；
• 适合产品中大间距的器件，在精密场合无法做到。

DPC（直接镀铜）

主要通过蒸发、磁控溅射等表面沉积制程是在基板表面进行金属化，先在真空溅射下镀上钛金属，然后是铜粒子，镀上一定厚度，再用普通PCB工艺完成线路制作，然后再以电镀/化学镀的方式增加线路厚度，DPC的制备方式包含真空镀膜、湿法沉积、曝光显影、蚀刻等工序。

其优点有：

• 在外形加工方面，DPC陶瓷板需要激光切割，传统钻铣机、冲床无法精确加工，因此合力和线宽也更细；
• 金属结晶性能好；
• 平整度好；
• 线条不易脱落；
• 线条位置更精准，线条间距更小，可靠稳定，可过孔等优点；

其缺点有：

只能制作薄板（厚度<300μm），成本高，产值受限，导致经常出现出货时间不能按时的情况；

AMB（活性金属钎焊）

它是利用钎料中的少量活性元素Ti、Zr与陶瓷发生反应，形成可被液态钎料润湿的反应层，从而实现陶瓷与金属的结合。

其优点在于：

该结合是通过陶瓷与活性金属焊膏在高温下发生化学反应而实现的，因此其结合强度较高，可靠性较好。

其缺点在于：

AMB工艺的可靠性很大程度上取决于活性钎料的成分、钎焊工艺、钎焊层结构等诸多关键因素。

厚膜

厚膜技术是直接在陶瓷基片上印刷图形，然后直接烧结的工艺。

优点：

• 与陶瓷的结合力比DPC工艺大很多；
• 是直接印刷图形，没有蚀刻、镀铜工序，成本会低一些；
• 是一次性成型，平整度比DPC更光滑。

缺点：

厚膜工艺因为是印刷，所以一般不会太厚，由于产品要求不同，材料不同对膜的导电性也有一定的影响。

所以很难说哪种工艺最好，要看客户的应用和使用情况，客户可以根据自己的情况选择每一种工艺他们的要求。

如果您有更多兴趣，请随时联系我们。

The metallized ceramic substrate is a kind of circuit board. It has a thermal expansion coefficient close to that of semiconductors and high heat resistance. It is suitable for products with high heat generation (high-brightness LED, solar energy), and its excellent weather resistance is more suitable for harsh outdoor environments. Because it has the characteristics of lead-free, non-toxic, and good chemical stability, it will not cause harm to environmental protection, so it is more and more widely accepted by the public.

Due to different processes, the ceramic substrate is mainly divided into DBC (Direct Bonded Copper), DPC (Direct Plated Copper), AMB (Active Metal Brazing), and Thick film.

We will introduce each of the processes and the advantages, disadvantages of each process.

DBC (Direct Bonded Copper)

It is composed of the ceramic substrate, bonding layer, and conductive layer. It refers to the special process of copper foil directly bonding to alumina or aluminum nitride ceramic substrate surface at high temperature.

The advantages are as below:

• The copper layer is thick;
• The processing is fast;
• The price is cheap;
• Can make multilayer;
• Suitable for large area consumption;
• High thermal conductivity;
• High adhesion strength;
• Excellent soft brazing;
• Excellent electrical insulation

The disadvantages are as below:

• Can not pass through the hole;
• Poor accuracy;
• Low flatness (surface roughness);
• Suitable for the device in the large distance of the product, can not be done in the precise occupation.

DPC (Direct Plated Copper)

Mainly by evaporation, magnetron sputtering and other surface deposition process to carry on the substrate surface metallization, first under the condition of vacuum sputtering, titanium, and then is copper particles, the plating thickness, then finish making line with ordinary PCB craft, and then to plating/electroless deposition way to increase the thickness of the line, the preparation of DPC way contains vacuum coating, wet deposition, Exposure development, etching, and other processes.

The advantages are as below:

• In terms of shape processing, DPC ceramic plate needs to be cut by laser, the traditional drilling and milling machine, and punch machine can not be accurately processed, so the combined force and line width are also finer.
• The crystal performance of the metal is good;
• The flatness is good;
• The line is not easy to fall off;
• The line position is more accurate, the line distance is smaller, reliable, and stable, can be through the hole and other advantages.

The disadvantages are as below:

It can only make a thin plate (thickness < 300μm), and its cost is high, the output value is limited, resulting in frequent shipment time can not be on time.

AMB (Active Metal Brazing)

It is a method to realize the bonding of ceramic and metal by reacting a small number of active elements Ti and Zr in filler metal with ceramics to form a reaction layer that can be wetted by liquid filler metal.

The advantages are as below:

The combination is achieved by the chemical reaction between ceramic and active metal solder paste at high temperatures, so its bonding strength is higher and reliability is better.

The disadvantages are as below:

The reliability of the AMB process depends largely on the composition of active filler metal, brazing process, brazing layer structure, and many other key factors.

Thick film

Thick film technology is straight on ceramic substrate printed graphics, then direct sintering process.

The advantages are as below:

• The bonding force with ceramic is much greater than that of the DPC process;
• It is direct printing of graphics, no etching, and copper plating process, so the cost will be lower;
• It is a one-time forming, so the flatness is smoother than that of the DPC.

The disadvantages are as below:

Because the thick film process is printed, it is generally not too thick. Due to different product requirements, different materials have a certain impact on the conductivity of the film.

So it is hard to say which process is best, it depends on the customer’s application and usage, customer could choose each of the processes according to their requirements.

Should you have more interests, pls feel free to contact us at any time.