PCB新聞 - HDI PCB板資料和分類的詳細說明

高頻板是指電磁頻率較高的專用電路板, which is used for high frequency (frequency greater than 300MHZ or wavelength less than 1 meter) and microwave (frequency greater than 3GHZ or wavelength less than 0.1 meter)

The PCB in the category is a circuit board produced by operating the departmental process of the popular rigid circuit board manufacturing method on the microwave substrate copper clad board or adopting a special treatment method. 一般來說, 高頻板可定義為頻率高於1GHz的電路板.

1、PCB高頻板的分類。

Ceramic filling thermosetting 材料
Processing methods:
The processing flow is similar to epoxy resin/glass woven cloth (FR4), 但薄板很脆，容易斷裂. 鑽孔和敲鑼時, 鑽嘴、鑼刀壽命降低2.0%.

2. PTFE (polytetrafluoroethylene) 材料
Processing method:

(1). Cutting 材料: It is necessary to save the shelter film cutting 材料 to avoid scratches and indentations

(2). Drilling:

2.1 Use a brand new drill (size 130), 一個接一個是最好的, the pressure of the presser foot is 40psi

2.2鋁板為蓋板, and then the 1mm melamine backing plate is used to hold the PTFE plate tightly

2.3鑽孔後, use an air gun to blow out the dust in the hole

2.4 Use the most constant drilling rig and drilling parameters (basically, 洞越小, 鑽孔速度越快, 晶片負載越小, the lower the return speed)

3. Via treatment
Plasma treatment or sodium naphthalene activation treatment is conducive to hole metallization

4. PTH Immersion Copper

4.1 After micro-etching (with a micro-etching rate of 20 microinches controlled), start the board from the de-oil tank in the PTH pull

4.2如有必要, 通過第二個PTH, just start with the estimated cylinder and enter the board

5. Solder mask

5.1預處理：對盤子進行酸洗, and do not use machines to grind the plates

5.2 Pre-treatment and post-baking plate (90 degree Celsius, 30min), brush with green oil to cure

5.33階段烘烤：一階段為80°C, 100°C, 150°C, each for 30 minutes (if the substrate surface is oiled, it can be reworked: wash off the green oil and reactivate it)

6. Gong board

Lay the white paper on the circuit surface of the PTFE board, 並用FR-4基板或厚度為1的酚醛基板夾緊.0MM etched to remove copper:

As shown in the picture: High frequency and high speed board 材料

When selecting the substrate used in the PCB for high-frequency circuits, 有必要專業檢查資料DK及其在不同頻率下的變換特性.

用於高速訊號傳輸要求, 或特性阻抗控制要求, 關注DF及其在頻率前提下的效能, 溫度和濕度.

在頻率變化的前提下, 普通基材的DK和DF值變化較大.

尤其是在1 MHz到1 GHz的頻率範圍內, 其DK和DF值發生顯著變化.

根據線上塗層, the DK value of ordinary epoxy resin-glass fiber cloth-based substrate 材料 (ordinary FR-4) at a frequency of 1MHz is 4.

7. 1GHz頻率下的DK值變為4.19. 1GHz以上, 其DK值的變化趨於陡峭.

其變化趨勢是隨著頻率的新增, and then become smaller (but the transformation amplitude is not large), 例如, 10GHz以下, 普通FR-4的DK值為4.15, 並且基板資料具有高速和高頻特性，頻率發生變化. 在環境下, DK值變化較小. 在1MHz到1GHz的過渡頻率下, DK主要連接到0.02比例轉換.

在頻率由低到高變化的前提下，其DK值趨於略有下降.

The dielectric loss factor (DF) of the ordinary substrate 材料 is affected by the frequency change (except for the change in the high-frequency scale) and the change in the DF value is greater than the DK.

其轉型規律趨於增强, 所以在評估基板資料的高頻特性時, 其審查的重點是其DF值轉換環境.

用於具有高速和高頻特性的基板資料, 就高頻變換特性而言，普通基底資料有兩種不同類型：一種類型隨頻率變化, and its (DF) value changes very little .

另一種類型在轉變幅度方面接近於普通基底資料, but its own (DF) value is lower.