Zn diffusion in Ga

1-x

Al

x

As and GaAs was studied in the temperature range from 720℃ to 750℃. The relation of the junction depth (xi) with the time (t) and the temperature (T) of diffusion has been investigated. The variation of junction depth (xi) with aluminium composition was also investigated. ZnAs

2

dissociates during the reaction ZnAs

2

⇔1/3Zn

3

As

2

+1/3As

4

. The amounts of ZnAs

2

was about lmg/cm

3

each time.Fig.3 shows that at T=740℃ the junction depth (

X

j

) varies with the square root of the diffusion time for Zn diffusion in Ga

1-x

Al

x

AS

GaAs and GaAs

1-x

P.