關於電阻的設計

squirrel316

在CMOS製程中
: a6 L  t' e' c6 o3 k大致上可以知道說阻值等於sheet resistance*(L/W)
不過我有個問題就是L跟W值的選取
# w" E& h: M: q9 s* X- m假設我要讓L/W=2
我可以有很多種選擇 像是2u/1u 4u/2u ...等
& t4 }) ^+ ]& e7 {那請問一下這幾種選擇除了雜散電容造成的影響之外
: k  G" r: G+ o; E還會有什麼影響
謝謝指教

seanyang1337

Dear squirrel316,
Basicly, the W should big enought and has a low bond(usually 2u for above 0.35um).
If you using too small scale like 1um, the accuracy will be very poor.
' T/ `" h0 z- {+ dAnd it should be considered the eatch value.
As a reference, the foundry resistor test key, was measured by 10u/10u or larger.