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PCBボードにおけるアルカリエッチングの共通原因と解決策
PCBブログ
PCBボードにおけるアルカリエッチングの共通原因と解決策

PCBボードにおけるアルカリエッチングの共通原因と解決策

2021-12-30
View:267
Author:pcb

1. 問題:エッチング速度 PCBボード is reduced
Reason: due to improper control of process parameters
Solution: According to the process requirements, 温度などのプロセスパラメータをチェック, 噴霧圧力, 溶液比重, プロセス仕様に対するpH値と塩化アンモニウム含有量.

2. 課題:エッチング液の沈殿 PCBボード
Reason: (1) The content of ammonia is too low; (2) The water is too diluted; (3) The specific gravity of the solution is too large.
Solution:
(1) Adjust the PH value to reach the specified value of the process or appropriately reduce the exhaust air volume.
(2) Strictly follow the regulations of the process requirements or appropriately reduce the exhaust air volume when adjusting.
(3) Discharge part of the solution with high specific gravity according to the process requirements. アフターアナリシス, エッチング溶液の比重をプロセスの許容範囲に調整するために、塩化アンモニウムとアンモニアの水溶液を加える.

PCBボード

3. 問題:金属腐食防止コーティング PCBボード is eroded
Reason: (1) the pH value of the etching solution is too low; (2) the chloride ion content is too high.
Solution: (1) Adjust the PH value according to the process regulations; (2) Adjust the chloride ion concentration to the process regulations.

4. 問題:銅の表面 PCBボード 黒いです, and the etching does not move
Reason: The sodium chloride content in the etching solution is too low
Solution: Adjust the sodium chloride to the specified value of the process according to the process requirements.

5. 問題:基板の表面に残留銅がある PCBボード
Reason: (1) The etching time is not enough; (2) The film is not clean or there is corrosion-resistant metal.
Solution: (1) Carry out the first test according to the process requirements to determine the etching time (that is, adjust the transmission speed); (2) Check the board surface according to the process requirements before etching, 残留膜を必要としない耐食性金属浸透を必要としない.

6. 問題:基板の両面におけるエッチング効果 PCBボード is obviously different
Reason:
(1) The nozzle of the etching section of the equipment is blocked;
(2) The conveying rollers in the equipment must be staggered before and after each rod, otherwise it will cause traces on the board;
(3) Water leakage in the nozzle causes the spray pressure to drop (often appearing at the joints of the nozzle and the manifold);
(4) The solution in the preparation tank is insufficient, モータを動かすこと.
Solution:
(1) Check the blockage of the nozzle and clean it in a targeted manner;
(2) Re-examine thoroughly and arrange the staggered positions of the rollers of each section of the equipment;
(3) Check each joint of the パイプライン, repair and maintain it;
(4) Observe frequently and make supplements in time to the positions specified in the process.

7. 問題:その上の不均一なエッチング PCBボード leaves some residual copper
Reason:
(1) The film removal on the substrate surface is not complete enough, and there is residual film;
(2) The thickness of the copper plating layer on the board surface is uneven when the whole board is copper-plated;
(3) When the board surface is corrected or repaired with ink, エッチング装置の駆動ローラに染色される.
Solution:
(1) The film removal on the substrate surface is not complete enough, and there is residual film;
(2) The thickness of the copper plating layer on the board surface is uneven when the whole board is copper-plated;
(3) When the board surface is corrected or repaired with ink, it is stained on the driving roller of the etching machine;
(4) Check the unwinding process conditions, adjust and improve them;
(5) According to the density of the circuit pattern and the accuracy of the wire, 銅層の厚さの整合性を確保する, and the brushing and flattening process can be used;
(6) The repaired ink must be cured, そして、汚染されたローラーは検査されて、掃除されなければなりません.

PCBボード

8. 問題:エッチング後 PCBボード, 電線はひどく腐食している.
Reason: (1) The nozzle angle is wrong, and the nozzle is out of adjustment; (2) The spray pressure is too large, causing rebound and serious side erosion
Solution: (1) Adjust the nozzle angle and nozzle to meet the technical requirements according to the instructions; (2) According to the process requirements, the spray pressure is usually set to 20-30PSIG and adjusted by the process test method

9. 問題:基板は、コンベアベルト上で前方に移動 PCBボード shows a phenomenon of oblique walking
Reason:
(1) The level of equipment installation is poor;
(2) The nozzles in the etching machine will automatically reciprocate left and right. いくつかのノズルが正しく揺れない可能性があります, causing uneven spray pressure on the plate surface and causing the substrate to tilt;
(3) The damage to the gear of the conveyor belt of the etching machine causes the stop of part of the transmission wheel rod;
(4) The transmission rod in the etching machine is bent or twisted;
(5) The squeezing water stop roller is damaged;
(6) The position of part of the baffle of the etching machine is too low to block the conveying board;
(7) The upper and lower spray pressure of the etching machine is not uniform, そして、下の圧力が大きすぎるとき、板は上がるでしょう.
Solution:
(1) Adjust according to the equipment manual, 各セクションのローラーの水平角度と配置を調整する, which should meet the technical requirements;
(2) Check in detail whether the swing of each section of the nozzle is correct, and adjust according to the equipment manual;
(3) Inspect section by section in accordance with process requirements, and replace damaged or damaged gears and rollers;
(4) Replace the damaged transmission rod after detailed inspection;
(5) The damaged accessories should be replaced;
(6) After inspection, the angle and height of the baffle should be adjusted according to the equipment manual;
(7) Adjust the spray pressure appropriately.

10. 問題:銅は、上の回路で完全に腐食されません PCBボード, and there is residual copper on some edges
Reason:
(1) The dry film is not completely removed (it may be difficult to remove the film due to the thick and widening of the copper and tin-lead plating twice to cover a small amount of dry film);
(2) The conveyor belt speed in the etching machine is too fast;
(3) During tin-lead plating, メッキ液はドライフィルムの底部に浸透し、メッキ層によって汚染された非常に薄いドライフィルムを引き起こす, その場所で銅の腐食を遅くする, ワイヤの端に残留銅を残す.
Solution:
(1) Check the removal of the film, strictly control the thickness of the coating to avoid extension of the coating;
(2) Adjust the conveyor belt speed of the etching machine according to the etching quality;
(3) A. 撮影手順をチェック, 適切な撮影温度と圧力を選択, そして、乾燥したフィルムの銅表層への粘着性を改良する. B. 撮影前に銅表面の粗面化状態を確認.

11. 問題:両方の両側にエッチング効果 PCBボード is not synchronized
Reason: (1) The thickness of the copper layer on both sides is inconsistent; (2) The upper and lower spray pressures are uneven
Solution: (1) A adjusts the upper and lower spray pressure according to the thickness of the coating on both sides (the thickness of the copper layer faces downward); B uses single-sided etching to only activate the lower nozzle pressure. (2) A. エッチングボードの品質によると, 上部と下部の噴霧圧力をチェックし、それらを調整するB. エッチング装置のエッチング部のノズルがブロックされているかどうかを調べる, 上部と下部のスプレー圧力を調整するテストボードを使用して.

12. 課題:アルカリエッチング溶液の過剰結晶化 PCBボード
Reason:
When the pH value of the alkaline etching solution is lower than 80, 溶解度が悪くなる, resulting in the formation of copper salt precipitation and crystallization
Solution:
(1) Check whether the amount of sub-liquid in the spare tank for 補充 is sufficient.
(2) Check whether the controller, pipeline, ポンプ, 電磁弁, etc. 液体の補充は異常にブロックされる.
(3) Check whether excessive ventilation has caused a large amount of ammonia to escape and cause the PH to drop.
(4) Check whether the function of the PH meter is normal.

13. 問題:連続エッチング中にエッチング速度が低下する PCBボード, but the etching speed can be restored if the machine is stopped for a period of time
Reason: The ventilation volume is too low, resulting in insufficient oxygen supplementation
Solution: (1) Find out the correct amount of air extraction through the process test method; (2) Debug according to the instructions provided by the supplier to find out the correct data.

14. Problem: The photoresist comes off (dry film or ink)
Reason:
(1) The pH value of the etching solution is too high, the alkaline water-soluble dry film and the ink are easily damaged
(2) The sub-liquid replenishment system is out of control
(3) The type of photoresist itself is incorrect, and the alkali resistance is poor
Solution:
(1) Adjust according to the value determined by the process specification.
(2) Detect the PH value of the sub-liquid, 適正換気, そして、アンモニアガスが直接ボードの輸送領域に入るのを許しません.
(3) A good dry film can withstand PH=9 or more. B. ドライフィルムのアルカリ抵抗をテストするためにプロセステスト方法を使用してください.

15. 問題:ワイヤの過度のエッチング PCBボード becomes thinner
Reason:
(1) The transmission speed of the conveyor belt is too slow
(2) Side erosion will increase when PH is too high
(3) The specific gravity of the etching solution is lower than the specified value
Solution:
(1) Check the relationship between the thickness of the copper layer and the transmission speed, and set the operating parameters;
(2) Detect the pH of the etching solution, それがプロセスによって指定された範囲より高いならば, strengthen the ventilation until it returns to normal;
(3) Detect the specific gravity value. 設定値より低い場合, 銅塩を加え、副液のサプリメントを止める, 特定の重力値がプロセスによって指定された範囲まで上昇するように.

16. 問題:不十分なエッチング PCBボード, too large residual foot
Reason:
(1) The transmission speed of the conveyor belt is too fast
(2) The pH of the etching solution is too low (its value has little effect on the etching speed, しかし、pHが減少するとき, サイドエロージョンを減らす, but the residual foot will become larger)
(3) The specific gravity of the etching solution exceeds the normal value (the specific gravity has little effect on the etching speed, しかし、比重が増加すると, the side etching will decrease)
(4) Insufficient etching solution temperature
(5) Insufficient spray pressure
Solution:
(1) Check the relationship between the thickness of the copper layer and the transmission speed of the etching machine, そして、プロセステスト方法によって動作条件を見つける.
(2) Detect the pH value of the etching solution. 値が80より小さいとき, それを増やす方法を採用する必要があります, アンモニアを加えるか、液体補充を促進して、草案を減らすことのような.
(3) A detects the specific gravity value of the etching solution, そして、プロセスの指定された範囲に比重値を減らすために、より多くの副液体を加えます. サブ液供給システムが故障しているかどうかを調べる.
(4) Check whether the function of the heater is abnormal.
(5) A. スプレー圧チェック, そしてそれをcobwebの状態に調整します. ポンプかパイプラインが異常かどうかチェックする. C. 準備タンクの水位が低すぎる, ポンプが乾く原因となる. 液面制御の操作手順をチェックする, replenishment, 吐出ポンプ PCBボード.