A Ge specimen is doped with Al. The concentra | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) When a $Ge$ specimen is doped with $Al$ (a trivalent impurity),it becomes a $p$-type semiconductor.The concentration of acceptor atoms $(N_A)$ is

Vedclass · Accepted Answer

$10^{17} /m^3$

Vedclass · Answer

(A) When a $Ge$ specimen is doped with $Al$ (a trivalent impurity),it becomes a $p$-type semiconductor.The concentration of acceptor atoms $(N_A)$ is approximately equal to the concentration of holes $(p_0)$: $p_0 \approx N_A = 10^{21} /m^3$.According to the law of mass action for semiconductors,the product of the concentration of electrons $(n_0)$ and holes $(p_0)$ is equal to the square of the intrinsic carrier concentration $(n_i)$:$n_i^2 = n_0 	imes p_0$Given:$n_i = 10^{19} /m^3$$p_0 = 10^{21} /m^3$Substituting the values:$(10^{19})^2 = n_0 	imes 10^{21}$$10^{38} = n_0 	imes 10^{21}$$n_0 = \frac{10^{38}}{10^{21}} = 10^{17} /m^3$Thus,the concentration of electrons in the specimen is $10^{17} /m^3$.

$A$ $Ge$ specimen is doped with $Al$. The concentration of acceptor atoms is $\sim 10^{21} \text{ atoms}/m^3$. Given that the intrinsic concentration of electron-hole pairs is $\sim 10^{19} /m^3$,the concentration of electrons in the specimen is:

Similar Questions

The maximum value of $\left(\frac{1}{x}\right)^{x}$ is

If the harmonic mean between the roots of $(5+\sqrt{2}) x^2-b x+(8+2 \sqrt{5})=0$ is $4$,then the value of $b$ is

The solution of $\frac{dy}{dx} + 1 = e^{x+y}$ is

The sensitivity of a galvanometer is $60 \text{ div/A}$. When a shunt is used,its sensitivity becomes $10 \text{ div/A}$. If the resistance of the galvanometer is $20 \ \Omega$,then the value of the shunt used is: (in $\Omega$)

$A$ class has $15$ boys and $5$ girls. Suppose $3$ students are selected at random from the class. The probability that there are $2$ boys and $1$ girl is

Vedclass Test Series

Exam Paper Generator

Online Exam Module