Solid hatch command problem

[amingame7]

Hi guys

I am amateur in using Auto cad and this time face strange problem in using hatch command( solid ).When I use hatch command inside my drawing some unknown are is creating which is not in my drawing and make a separating lines between uni surface!! I am completely wondering what is going on and I even redraw every lines as poly line and used hatch command but it was useless! I am not sure but I am think it is related to some option.The related Image is uploaded to convey my problem .

In addition when I export to pdf most of straight lines become somehow curvy and ruin all drawing.it dosent have enough accuracy and precision in all drawing I should draw at size of micron and nano meter.

 

Please help me

Thank u