Hi Andy,
Please refer 2.9.7, IPC-A-600, tenting for via holes.
Translation for tented via is 掩孔. Some vias needed to be covered or tented by solder mask. 
There are only 3 kinds of vias till now. One is PTH via which could be seen from both sides of the board. Second is blind via which could be seen from one side of the board. The third one is called buried vias which could be seen on neither side of the board. PTH and/or blind vias might need to be tented or covered by either solder mask or some other specific resin materials. 
 
Regards
 
Leesha Peng 彭丽霞
技术与培训部总监 
Director Technical and Training Program
IPC WOFE, a subsidiary of IPC, Inc.
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________________________________

From: TGAsia 代表 Duan, Shi Hao - Andy BSCE QA PEK
Sent: 2006-9-26 (星期二) 22:06
To: [log in to unmask]
Subject: [TGA] Help me...


Dear all,
     Who knows what's Tented and Covered via?  How many via types is used for electronics assembly?

Best regards,
 
Duan Shi Hao (Andy)
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