Why are women carriers for the disease hemophilia and men are not?

Hemophilia A and B
Hemophilia A and B occur almost always in boys. Generally, hemophilia A and B pass from mother to son through one of the mother's genes. Everyone has two sex chromosomes, one from each parent. Females inherit an X chromosome from their mother and an X chromosome from their father. Males inherit an X chromosome from their mother and a Y chromosome from their father. The gene that causes hemophilia A or B is located on the X chromosome. This is why men can't pass along the gene that causes hemophilia to their sons. Most women who have the defective gene are simply carriers and exhibit no signs or symptoms of hemophilia. It's also possible for hemophilia A or B to occur through spontaneous gene mutation.

Hemophilia C
Hemophilia C can occur in both boys and girls. The defective gene that causes hemophilia C can also be passed on to children by mothers and fathers, but it follows an inheritance pattern different from that which occurs with hemophilia A and B.

apparently hemophilia is linked to the X chromosome.

Females possess two X-chromosomes, whereas males have one X and one Y chromosome. Since the mutations causing the disease are recessive, a woman carrying the defect on one of her X-chromosomes may not be affected by it, as the equivalent allele on her other chromosome should express itself to produce the necessary clotting factors. However the Y-chromosome in men has no gene for factors VIII or IX. If the genes responsible for production of factor VIII or factor IX present on a male's X-chromosome is deficient there is no equivalent on the Y-chromosome, so the deficient gene is not masked by the dominant allele and he will develop the illness.

Since a male receives his single X-chromosome from his mother, the son of a healthy female silently carrying the deficient gene will have a 50% chance of inheriting that gene from her and with it the disease; and if his mother is affected with haemophilia, he will have a 100% chance of being a haemophiliac. In contrast, for a female to inherit the disease, she must receive two deficient X-chromosomes, one from her mother and the other from her father (who must therefore be a haemophiliac himself). Hence haemophilia is far more common among males than females. However it is possible for female carriers to become mild haemophiliacs due to lyonisation of the X chromosomes. Haemophiliac daughters are more common than they once were, as improved treatments for the disease have allowed more haemophiliac males to survive to adulthood and become parents. Adult females may experience menorrhagia (heavy periods) due to the bleeding tendency. The pattern of inheritance is criss-cross type. This type of pattern is also seen in colour blindness.

males have XY chromosomes
females have XX chromosomes

hemophilia is a sex-linked recessive disorder meaning it is on the X chromosome, the only way for a recessive disorder to occur is if there is no Y chromosome to shut it off, so only XX have it, there are mutations-rare cases of male carriers for disease

Because men have and XY and the Y doesnt carry much, if anything. And since women pass the X on to the boy and the boy's Y can't cover up for the hemophilia gene, boys get it.