一、噴淋清洗
1、 Spray cleaning
上噴淋管路共有兩路,形成相互交叉噴淋,但去離子水不宜直接噴淋沖洗晶圓表面,因晶圓在水蝕作用下直接噴淋晶圓表面,易產(chǎn)生微粒污泥而污染晶圓表面,因此,在去離子水的噴淋過程中,需要對沖洗水壓、水量、方向和角度作出調(diào)整測試,以達到微粒污染少的較好效果。 良好的噴嘴所噴淋范圍涵蓋全部晶圓及片盒; 而不良的噴淋沖洗形狀,沒有涵蓋全部晶圓及片盒,未被噴淋沖洗的死角地帶,微粒、雜質(zhì)及化學藥液殘留含量仍然很高,而達不到良好的清洗效果。
There are two paths in the upper spray pipeline to form cross spray, but it is not suitable to spray deionized water directly to wash the wafer surface. Because the wafer is directly sprayed on the wafer surface under the action of water erosion, it is easy to produce particulate sludge and pollute the wafer surface. Therefore, in the process of spraying deionized water, it is necessary to adjust and test the flushing water pressure, water volume, direction and angle, In order to achieve the better effect of less particle pollution. The spray range of a good nozzle covers all wafers and cassettes; However, the poor spray washing shape does not cover all the wafers and cassettes, and the content of particles, impurities and chemical residues is still very high in the non spray washing dead area, which can not achieve good cleaning effect.
二、鼓泡沖浪清洗
2、 Bubble surf cleaning
上噴淋同時,下噴淋管路由底部兩側(cè)不斷進水,而后由內(nèi)槽上沿四周溢出,這樣,每個晶圓片縫、各處邊角的去離子水都能連續(xù)得到更新。 同時,純凈氣體(氮氣或壓縮空氣)由下噴淋管路進入槽體。鼓泡有以下幾個作用:
At the same time, water continuously enters the bottom of the lower spray pipe, and then overflows from the top of the inner groove, so that the deionized water in each wafer slot and each corner can be continuously updated. At the same time, the pure gas (nitrogen or compressed air) enters the tank through the lower spray pipe. Bubbling has the following functions:
(1)增加了去離子水的沖刷力,對槽體本身有很好的自清洗作用;
(1) It increases the scouring force of deionized water and has a good self-cleaning effect on the tank itself;
(2)晶圓在水流中顫動,氣泡不能沾附其上,提高了沖洗效果;
(2) The wafers vibrate in the water and the bubbles can't adhere to them, which improves the washing effect;
(3)氮氣鼓泡減少去離子水中的含氧量,避免在晶圓表面生成氧化物。
(3) Nitrogen bubbling reduces oxygen content in deionized water and avoids oxide formation on wafer surface.
三、超聲波清洗
3、 Ultrasonic cleaning
蘇州富怡達超聲波有限公司的QDR增加了超聲波功能選項,與鼓泡沖浪清洗交替作用,極大的提高了清洗效率,并有效降低DI水的消耗量。典型的應用方法是:上噴淋+排放→上噴淋+下進水→超聲+上噴淋+溢流→鼓泡+上噴淋+溢流→快排放
The QDR of Suzhou fuyida ultrasonic Co., Ltd. has added ultrasonic function option, which alternates with bubble surfing cleaning, greatly improving cleaning efficiency and effectively reducing DI water consumption. The typical application method is: upper spray + discharge → upper spray + lower water inflow → ultrasonic + upper spray + overflow → bubbling + upper spray + overflow → fast discharge
四、快沖快排
4、 Let's go, let's go
噴淋注滿水時間和排水時間,對晶圓清洗質(zhì)量有很大影響。 因晶圓表面暴露在空氣中會接觸空氣中的氧分子或水汽,在常溫下,即會生長一層很薄的氧化層(約為 0.5~1 nm),這層自然氧化物的厚度與暴露在空氣中的時間長短有關, 因此,噴淋注滿水時間越長,晶圓暴露在空氣中的時間就會越長,因而形成的氧化層也越厚,這對晶圓清洗,是很不利的。 QDR 排水的時間越短,排水流速就會越大,有利于去離子水帶走晶圓表面上的微粒雜質(zhì)。因此,在 QDR 設計中,要盡可能的縮短噴淋注滿水時間和排水時間,實現(xiàn)快沖快排,整體效率也會得到提高。富怡達超聲波的QDR快排及注水時間指標為:注入時間:≤120秒,排放時間:≤12秒。
The filling time and draining time of spray have great influence on wafer cleaning quality. Because the wafer surface is exposed to the air, it will contact the oxygen molecules or water vapor in the air. At room temperature, a thin oxide layer (about 0.5 ~ 1 nm) will grow. The thickness of this layer of natural oxide is related to the time of exposure to the air. Therefore, the longer the spraying time is, the longer the wafer will be exposed to the air, and the thicker the oxide layer will be, This is bad for wafer cleaning. The shorter the QDR drainage time, the higher the drainage flow rate, which is conducive to deionized water to remove the particles on the wafer surface. Therefore, in the QDR design, it is necessary to shorten the spray filling time and drainage time as much as possible, realize fast flushing and fast drainage, and improve the overall efficiency. The QDR quick discharge and water injection time indexes of fuyida ultrasonic are: injection time: ≤ 120 seconds, discharge time: ≤ 12 seconds.